Difference between revisions of "Battery Electric Vehicle Platforms"

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(Created page with "=Technology Roadmap Sections and Deliverables= The first point is that each technology roadmap should have a clear and unique identifier: * '''2SEA - Solar Electric Aircraft''' This indicates that we are dealing with a “level 2” roadmap at the product level (see Fig. 8-5), where “level 1” would indicate a market level roadmap and “level 3” or “level 4” would indicate an individual technology roadmap. ==Roadmap Overview== The working principle and arch...")
 
 
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Roadmap Creators: [https://www.linkedin.com/in/michaelpeters2015/ Michael Peters], [https://www.linkedin.com/in/hiroki-ogasawara/ Hiro Ogasawara], [https://www.linkedin.com/in/piyushkumbhare/ Piyush Kumbhare]
Time Stamp: 5 December 2023
=Technology Roadmap Sections and Deliverables=
=Technology Roadmap Sections and Deliverables=
* '''2BEV - Battery Electric Vehicle Platforms'''
The Battery Electric Vehicle (BEV) platform, a level 2 roadmap, represents the critical product/system of the Battery Electric Platform that is integrated within a broader electrified vehicle. The level 1 system above the BEV is the electrified vehicle market segment, which includes other types of electrified vehicles (e.g., FCEV's, PHEV's, etc.) as well as the other vital systems that comprise electrified vehicles (e.g., steer-by-wire systems). Level 3 roadmaps represent critical subsystems within a BEV platform-based electrified vehicle, and level 4 roadmaps would indicate an individual component technology roadmap.
==Roadmap Overview==


The first point is that each technology roadmap should have a clear and unique identifier:
Electrified vehicles are vehicles that utilize electric power (from a variety of different sources, such as batteries or fuel cells) to power an electric motor-based propulsion system. Examples of electrified vehicles that exist on the road today include plug-in hybrid electric vehicles (PHEV), fuel cell electric vehicles (FCV or FCEV) and battery electric vehicles (BEV). Electrified vehicles are an increasingly popular alternative to traditional gas-powered vehicles that generate propulsion through internal combustion engines. Electrified vehicles are one part of a broader ecosystem of solutions being used to combat the evolving problem/challenge of climate change. Electric vehicles help to solve this problem by providing humanity with an alternate mode of transportation that does not produce harmful greenhouse gas emissions.  
* '''2SEA - Solar Electric Aircraft'''
This indicates that we are dealing with a “level 2” roadmap at the product level (see Fig. 8-5), where “level 1” would indicate a market level roadmap and “level 3” or “level 4” would indicate an individual technology roadmap.


==Roadmap Overview==
This roadmap will focus specifically on the battery electric vehicle (BEV) platform. BEV platforms are becoming increasingly popular as consumers seek different options within the electric vehicle market, and manufacturers look for ways to meet this customer demand through the use of modular architectures that multiple different vehicle variants may be built upon. Modular architectures/platforms for battery electric vehicles are typically comprised of a battery pack, on board charging module, integrated power electronics, drive units, and a chassis with a wheelbase. Multiple different vehicle bodies and accompanying features may then be built upon these platforms. Below are examples of BEV platforms being produced today (one by Tesla Motors, and one by General Motors) [1],[2],[3],[4].


The working principle and architecture of solar-electric aircraft is depicted in the below.  
[[File:Tesla Motors BEV.jpg|400px|center]]


[[File:Section 1.JPG]]
Automotive manufacturers today often refer to these types of BEV platform designs as "skateboards", as they are built around the chassis and wheel base and allow for different architectures to be built on top of them. Developing platform and modular designs represents a strategic decision from auto manufacturers, who have historically suffered cost overruns due to the number of different vehicle variants and configurations that are possible in their existing vehicle offering/lineup. Platforming battery electric vehicles reduces the proliferation of possible vehicle variants, reduces manufacturing complexity and the cost to setup manufacturing lines, reduces the cost of vehicles by enabling increased strategic buying patterns, and often results in increased vehicle quality.


Solar-electric aircraft are built from light-weight materials such as wood or carbon-fiber reinforced polymers (CFRP) and harvest solar energy through the photoelectric effect by bonding thin film solar cells to the surface of the main wings, and potentially the fuselage and empennage as well. The electrical energy harvested during the day is then stored in on-board chemical batteries (e.g. Lithium-Ion, Lithium-Sulfur etc…) and used for propelling the aircraft at all times, including at night. For the system to work there needs to be an overproduction of energy during the day, so that the aircraft can use the stored energy to stay aloft at night. The flight altitude of about 60,000-70,000 feet is critical to stay above the clouds and not to interfere with commercial air traffic. Depending on the length of day, i.e. the diurnal cycle which determines the number of sunshine hours per day, which itself depends on the latitude and time-of-year (seasonality) the problem is easier or harder. The reference case in the technology roadmap is an equatorial mission (latitude = zero) with 12 hours of day and 12 hours of night.
[[File:GM Ultium BEV 2.jpg|400px]] [[File:Hyundai BEV.jpeg|500px]] [[File:BEV Platform Chassis.jpg|500px]]


==Design Structure Matrix (DSM) Allocation==
==Design Structure Matrix (DSM) Allocation==


[[File:Section 2.JPG]]
Our technology of interest, battery electric vehicle platforms, is identified in the DSM below with dark blue highlighting at level 2 (2BEV). Additionally, we also show a tree structure that decomposes into the systems, and subsystems that comprise our level 2 technology. The DSM shows how these critical systems and subsystems interact to comprise the battery electric vehicle platform. For example, we see that a critical subsystem is the level 3 battery pack module, which is color-coded to indicate that it has its own, existing technology roadmap (3ESB - [[Energy_Storage_via_Battery]]). The battery pack module (or Energy Storage Battery) is comprised of the battery cells, pack structure, and other subsystems. The battery cells break down into their individual components (anode, cathode, etc.) that generate electrons to conduct electricity. However, we also see the interdependency between the battery pack structure and the high voltage cables, which in turn have a connection to the power inverter module. All this is to say that the interconnected nature of subsystems within a BEV platform critically come together to create the emergence exhibited by a battery electric vehicle.


The 2-SEA tree that we can extract from the DSM above shows us that the Solar-Electric Aircraft (2SEA) is part of a larger company-wide initiative on electrification of flight (1ELE), and that it requires the following key enabling technologies at the subsystem level: 3CFP Carbon Fiber Polymers, 3HEP Hybrid Electric Propulsion and 3EPS Non-Propulsive Energy Management (e.g. this includes the management of the charge-discharge cycle of the batteries during the day-night cycle). In turn these require enabling technologies at level 4, the technology component level: 4CMP components made from CFRP (spars, wing box, fairings …), 4EMT electric machines (motors and generators), 4ENS energy sources (such as thin film photovoltaics bonded to flight surfaces) and 4STO (energy storage in the form of lithium-type batteries).
 
[[File:2BEV DSM v2.png|600px]] [[File:2BEV Tree v2.png|300px]]


==Roadmap Model using OPM==
==Roadmap Model using OPM==
We provide an Object-Process-Diagram (OPD)  of the 2SEA roadmap in the figure below. This diagram captures the main object of the roadmap (Solar-Electric Aircraft), its various instances including main competitors, its decomposition into subsystems (wing, battery, e-motor …), its characterization by Figures of Merit (FOMs) as well as the main processes (Flying, Recharging).


[[File:Section 3.JPG]]
We provide an Object-Process-Diagram (OPD) of the Battery Electric Vehicle (BEV) Platform in the figure below. This diagrams captures the main object of the technology (Battery Electric Vehicle), the value-generating processes and different instruments associated with their characterization by Figures of Merit (FoM).
 
The OPD shows that the BEV platform can be decomposed into five main modules - the onboard charger, the battery pack, the engine control unit, the power inverter, and the electric drivetrain. The OPD depicts how these modules interact with one another to generate power at the wheelbase of the BEV platform. In short, the OPD shows that external power can be provided to the BEV platform by charging the battery to a high (up to 100%) state of charge. Once charged, the battery cells within the battery pack module react and create voltage and current that is conducted and then discharged from the battery pack. The engine control unit, which is operated indirectly by a human/operator that is driving the battery electric vehicle, controls the rate of discharge of the battery. The Discharged power from the battery is output as DC power, and is then switched by the power inverter to AC power that turns the electric motor and is transformed into torque. The transmission, which is also controlled by the engine control unit, regulates the torque from low to high and enables the driveshaft to spin, resulting in vehicle acceleration (going from low to high). 


An Object-Process-Language (OPL) description of the roadmap scope is auto-generated and given below. It reflects the same content as the previous figure, but in a formal natural language.  
[[File:BEV OPM v4.jpg|1100px|center]]


[[File:Section 3_2.JPG]]
An Object-Process-Language (OPL) description of the roadmap scope is auto-generated and given in [[OPL_Battery_Electric_Vehicle]]. It reflects the same content as the previous figure, but in a formal natural language.


==Figures of Merit==
==Figures of Merit==
The table below show a list of FOMs by which solar electric aircraft can be assessed. The first four (shown in bold) are used to assess the aircraft itself. They are very similar to the FOMs that are used to compare traditional aircraft which are propelled by fossil fuels, the big difference being that 2SEA is essentially emissions free during flight operations. The other rows represent subordinated FOMs which impact the performance and cost of solar electric aircraft but are provided as outputs (primary FOMs) from lower level roadmaps at level 3 or level 4, see the DSM above.


[[File:Section 4_.JPG]]
The table below summarizes the figures of merit used to evaluate battery electric vehicle platform technologies. Some of these figures of merit, such as range and acceleration, are very similar to the figures of merit used to evaluate traditional automotive vehicle. Other figures of merit, such as power storage cost and charge rate, are critical to evaluating the battery pack technology employed within the battery electric vehicle as well as the battery electric vehicle platform itself. Finally, FOM's such as carbon dioxide emissions and kilometers per kilowatt are very specific FOM's to battery electric vehicle platform technologies in totality.
 
{| class="wikitable sortable" style="margin-left: auto; margin-right: auto; border: none;"
|-
! Figure of Merit (FOM) !! Unit !! Description
|-
| '''Range''' || [km] || The number of miles the vehicle can travel on a single full charge
|-
| '''Acceleration time''' || [s] || Time to accelerate to from 0 to 100 kmh (km per hour)
|-
| '''Motor Torque''' || [N.m] || Torque produced by the electric vehicle motor
|-
| Motor Efficiency || [%] || Percentage of energy discharged from the battery pack that is converted to mechanical energy
|-
| Kilometers per kilowatt || [km / kw] || The average distance the vehicle travels based upon the amount of energy used
|-
| '''Vehicle charge rate''' || [km/min] || The rate at which vehicle range (in km) is added to the BEV platform during charging
|-
| '''Power Storage Cost''' || [$/kWh] || Total cost of power storage within a BEV platform (at the battery pack level) in dollars per kilowatt
|-
| Carbon Dioxide Emissions || [g/km] || The total amount of carbon dioxide emissions generated by the vehicle platform per mile driven
|-
|}
 
Note: Key FOM's are highlighted in '''bold text'''
 
Below are some trends related to the figures of merit listed above. The charts show that the range of battery vehicles has been steadily increasing over the past decade, all while battery prices have rapidly declined. Both of these factors have contributed to increasing adoption of battery electric vehicle platforms, as the cost and performance of these systems continue to rise. Finally, charging trends are improving substantially, as new technology around superchargers enters the market (on both the BEV platform and charging station sides of the interface).


Besides defining what the FOMs are, this section of the roadmap should also contain the FOM trends over time dFOM/dt as well as some of the key governing equations that underpin the technology. These governing equations can be derived from physics (or chemistry, biology ..) or they can be empirically derived from a multivariate regression model. The table below shows an example of a key governing equation governing (solar-) electric aircraft.
[[File:FOM trends 4.jpg|1400px]]


[[File:Section 4_2.JPG]]
In addition to the figures of merit shown above, some of the key governing equations for battery electric vehicles are shown below.
 
{| class="wikitable sortable" style="margin-left: auto; margin-right: auto; border: none;"
|-
! Input !! Key Relationship or Governing Equation !! Output
|-
|
* P_out: Power output (mechanical power at driveshaft in watts)
* P_in: Power input (electrical power into the motor in watts)
|| ηm = P_out / P_in || ηm : motor efficiency (expressed as a %)
|-
|
*V_ac : Input voltage  (V)
*I_ac: Input current (A)
*p_f : power loss coefficient (often efficiency)
*N_rpm: speed of motor (in rpm)
|| T = (V_ac* I_ac * p_f ) / ((2π* N_rpm )/60) || T = motor torque
|-
|}


==Alignment with Company Strategic Drivers==
==Alignment with Company Strategic Drivers==
The table below shows an example of potential strategic drivers and alignment of the 2SEA technology roadmap with it.


[[File:Section 5.JPG]]
The Automotive industry as a whole is in the midst of significant disruption. The market is shifting as new entrants such as Tesla, Rivian, BYD, and others bring advanced technology and supporting capabilities to a customer base wanting change. As our organization prepares to remain competitive with the likes of Tesla, Rivians, and others, there are three key pillars to our response in the market. First is '''embracing the transportation transformation'''. This means that we must realize that our customer base has a desire for an entirely new propulsion option when choosing the vehicle that they purchase. Customers want a vehicle with low or no emissions, and as such we must be prepared to offer this to them. In our case, this will be via a battery electric vehicle. Second is '''modularity and commonization''' of key subsystems and components. A key success factor to our ability to deliver new BEV platforms will be ensuring that we have identified where we can modularize major sub-systems and components, so that they can be easily reused across current and future platforms. Our third pillar is '''interoperability and integration'''. Our fourth pillar is '''lifecycle carbon neutrality'''.As our vehicles go out into the market, they cannot operate on their own any longer. We need to ensure that we have a level of interoperability with new infrastructure being brought online (e.g., charging stations of any brand), and we also must ensure that our products are integrated in a way that allows us to track the performance of vehicles in the field, deliver insights and diagnostics, and provide new features and updates to our customers.  


The list of drivers shows that the company views HAPS as a potential new business and wants to develop it as a commercially viable (for profit) business (1). In order to do so, the technology roadmap performs some analysis - using the governing equations in the previous section - and formulates a set of FOM targets that state that such a UAV needs to achieve an endurance of 500 days (as opposed to the world record 26 days that was demonstrated in 2018) and should be able to carry a payload of 10 kg. The roadmap confirms that it is aligned with this driver. This means that the analysis, technology targets, and R&D projects contained in the roadmap (and hopefully funded by the R&D budget) support the strategic ambition stated by driver 1. The second driver, however, which is to use the HAPS program as a platform for developing an autonomy stack for both UAVs and satellites, is not currently aligned with the roadmap.
 
Listed below are the strategic drivers for the company, and the alignment targets of our roadmap with these drivers:
 
{| class="sortable wikitable" style="width: 75%;"
|-
! Number !! Strategic Drivers !! Alignment targets
|-
|  '''1''' ||  style="width: 50%"| To develop a battery electric vehicle platform that has an appropriate range for customers seeking to replace their existing internal combustion engine vehicle with a battery-powered electric vehicle. || ''' The 2BEV roadmap is aligned to this strategic driver.''' The battery electric vehicle platform roadmap will target 1000 km as the desired maximum range of the BEV platform that is developed. This is benchmarked off of the top-end range of internal combustion engine vehicles on the market today.
|-
|  '''2''' || To develop a set of battery electric vehicle platforms that will be utilized across all future vehicle production, with optimization of market segment coverage kept in mind and with the ability to scale the platform as necessary to meet the different needs of specific customers. The design of these platforms should minimize CAPEX and OPEX expenditures by allowing for engineering and design focus on a set of modular subsystems across platforms as well as commonization across manufacturing lines used to produce the platforms (reducing the cost of specified equipment). || '''The 2BEV roadmap is aligned to this strategic driver'''. This roadmap will support this strategic driver by identifying where modularity can be employed across a platform to better enable the optimization of platforms within market segments defined by the organization.
|-
|  '''3''' || To support integration of battery electric vehicle platforms with critical external interfaces to better enable customer experience in areas such as charging, vehicle feature release, etc. || ''' The 2BEV roadmap is aligned to this strategic driver.''' The battery electric vehicle platform roadmap will ensure compliance with the latest SAE charging protocols (e.g., charge port configuration), as well as other industry standards for key functions such as software development and deployment (e.g., AutoSar standards for OTA configuration).
|-
|  '''4''' || To engineer a Battery Electric Vehicle (BEV) platform with minimal carbon emissions throughout the vehicle's lifecycle, ensuring carbon neutrality. || ''' The 2BEV roadmap is aligned to this strategic driver.''' The battery electric vehicle platform roadmap will allocate 5% of its revenue to Research and Technology (R&T) projects to enhance battery efficiency and recyclability. The roadmap will include projects for lifecycle management, such as repurposing old car batteries in various applications.
|}
 
<br>


==Positioning of Company vs. Competition==
==Positioning of Company vs. Competition==
The figure below shows a summary of other electric and solar-electric aircraft from public data.


[[File:Section 6.JPG]]
The images and table below show examples of other battery electric vehicle platforms available on the market today (or previously available on the market) along with representative data points for key figures of merit that BEV platforms are evaluated upon (data compiled from evspecifications.com [11]).  


The aerobatic aircraft Extra 330LE by Siemens currently has the world record for the most powerful flight certified electric motor (260kW). The Pipistrel Alpha Electro is a small electric training aircraft which is not solar powered, but is in serial production. The Zephyr 7 is the previous version of Zephyr which established the prior endurance world record for solar-electric aircraft (14 days) in 2010. The Solar Impulse 2 was a single-piloted solar-powered aircraft that circumnavigated the globe in 2015-2016 in 17 stages, the longest being the one from Japan to Hawaii (118 hours).  
[[File:BEV Vehicles 2.png|1300px|center]]


SolarEagle  and Solara 50 were both very ambitious projects that aimed to launch solar-electric aircraft with very aggressive targets (endurace up to 5 years) and payloads up to 450 kg. Both of these projects were canceled prematurely. Why is that?
{| class="wikitable sortable" style="margin-left: auto; margin-right: auto; border: none;"
|-
! Manufacturer !! Model !! Model Year !! Range [km] !! Battery Size [kwh] !! Acceleration Time [s] !! Vehicle Charge Rate [km/min] || Max Torque [N.m] || Electric Drive Configuration
|-
| General Motors || Chevrolet Bolt || 2023 || 416 || 65 || 6.5 || 5.3 || 360 || Single Electric Motor (FWD)
|-
| Tesla || Model S (performance) || 2023 || 652 || 100 || 2.4 || 21.3 || 967 || Dual Electric Motors
|-
| Lucid || Air (Touring) || 2023 || 684 || 94 || 3.4 || 21.3 || 1200 || Dual Electric Motors
|-
| BMW || i5 M60 || 2024 || 411 || 84 || 3.7 || 14.5 || 795 || Dual Electric Motors
|-
| Subaru || Soltera || 2023 || 357 || 73 || 6.5 || 14.6 || 338 || Dual Electric Motors
|-
| Nissan || Leaf || 2011 || 118 || 24 || 9.9 || 4.6 || 280 || Single Electric Motor (FWD)
|-
| Kia || Soul || 2015 || 150 || 30.5 || 11.2 || 3.6 || 285 || Single Electric Motor (FWD)
|-
| Tesla || Model S || 2012 || 426.5 || 85 || 5.4 || 7.6 || 440 || Single Electric Motor (RWD)
|-
| General Motors || Chevrolet Spark || 2014 || 132 || 21.3 || 7.9 || 4.2 || 542 || Single Electric Motor (FWD)
|-
| Hyundai || IONIQ || 2023 || 581 || 77 || 5.1 || 25.8 || 350 || Dual Electric Motors
|-
| BYD || Qin plus EV Pilot Diamond Type || 2023 || 610 || 72 || 3.8 || 20.3 || 250 || Dual Electric Motors
|-
|}


[[File:Section 6_2.JPG]]
Below is a graph of range [km] vs vehicle charging rate [km/min] for the BEV platforms listed in the table above. This chart illustrates how the pareto front of BEV platform performance has shifted over time as it relates to the key FOM's of range and charging rate. In the bottom left of the chart, there is a cluster of early mass-production BEV platforms such as the Nissan Leaf and the Chevy Spark. In the middle of the chart, we see current-day BEV platforms such as the Chevy Bolt and BMW i5 M60. Towards the upper right side of the chart, we see a high-performing group of current-day BEV platforms in the Tesla Model S (performance), the Lucid Air, and the Hyundai Ioniq. This group of high-performing current-day mass production BEV platforms form the pareto front for existing advancement in BEV platform technology (Data from references [5], [6], and [7]).


The Pareto Front (see Chapter 5, Figure 5-20 for a definition) shown in black in the lower left corner of the graph shows the best tradeoff between endurance and payload for actually achieved electric flights by 2017. The Airbus Zephyr, Solar Impulse 2 and Pipistrel Alpha Electro all have flight records that anchor their position on this FOM chart. It is interesting to note that Solar Impulse 2 overheated its battery pack during its longest leg in 2015-2016 and therefore pushed the limits of battery technology available at that time. We can now see that both Solar Eagle in the upper right and Solara 50 were chasing FOM targets that were unachievable with the technology available at that time. The progression of the Pareto front shown in red corresponds to what might be a realistic Pareto Front progression by 2020. Airbus Zephyr Next Generation (NG) has already shown with its world record (624 hours endurance) that the upper left target (low payload mass - about 5-10 kg and high endurance of 600+ hours) is feasible. There are currently no plans for a Solar Impulse 3,  which could be a non-stop solar-electric circumnavigation with one pilot (and an autonomous co-pilot) which would require a non-stop flight of about 450 hours. A next generation E-Fan aircraft with an endurance of about 2.5 hours (all electric) also seems within reach for 2020. Then in green we set a potentially more ambitious target Pareto Front for 2030. This is the ambition of the 2SEA technology roadmap as expressed by strategic driver 1. We see that in the upper left the Solara 50 project which was started by Titan Aerospace, then acquired by Google, then cancelled, and which ran from about 2013-2017 had the right targets for about a 2030 Entry-into-Service (EIS), not for 2020 or sooner. The target set by Solar Eagle was even more utopian and may not be achievable before 2050 according to the 2SEA roadmap.
[[File:BEV Pareto v3.jpg|750px|center]]
 
This chart also shows how specific manufacturers have improved the performance of their technology over time, and what tradeoffs they have made in doing so. For example, General Motors (parent company of the brand Chevrolet) made significant improvements in vehicle range between their 2014 Chevy Spark and their 2023 Chevy Bolt. However, they made only marginal improvements in the performance of vehicle charging rate. On the other hand, Tesla made considerable improvements in both of these areas between their 2012 version of the Tesla Model S and their 2023 Tesla Model S (performance edition). It is also interesting to note that companies like Tesla truly appear to be pushing the Pareto front forward with their latest BEV platforms. They had the most advanced platform on the road when they introduced the model S in 2012, and the latest version of this BEV platform is also near the edge of the pareto front.


==Technical Model==
==Technical Model==
In order to assess the feasibility of technical (and financial) targets at the level of the 2SEA roadmap it is necessary to develop a technical model. The purpose of such a model is to explore the design tradespace and establish what are the active constraints in the system. The first step can be to establish a morphological matrix that shows the main technology selection alternatives that exist at the first level of decomposition, see the figure below.


[[File:Section 7_.JPG]]
In order to assess the feasibility of the technical targets that we have set, at the level of the battery electric vehicle platform roadmap, we have developed a technical model. The purpose of this model is to evaluate the sensitivity of key FOM's (representing progress in technology development) to individual variables that can be adjusted through different architectural and design decisions. As a first step, we have compiled a morphological matrix that represents a set of options available in our future architectural decision-making process:
 
 
[[File:BEV Matrix.jpg]]
 
 
The morphological matrix for the battery electric vehicle technology represents decisions that can be made around several of the underlying technologies that comprise battery electric vehicle platforms. The selection of different options in these categories represents an impact on individual variables that describe the governing range equation associated with battery electric vehicle performance. Specifically, the variables impacted are those in the parametrized equation representing vehicle driving range. Below is the equation for battery electric vehicle range [equation 1], as well as the decomposition of battery electric vehicle range into underlying, foundational variable parameters [equation 7] (derived from reference [12]). Adjustment to any of the variables shown below will impact the resultant range that a BEV platform may drive.
 
[[File:BEV equations mod2.png|600px]]
 
[[File:BEV Variables.jpg]]
 
The variables and equations above can then be used to develop a model for battery electric vehicle range based upon the constant speed (v) that the vehicle is driving at. Below is a graph of that model for an example BEV - the 2023 Chevy Bolt. Data for the Chevy bolt was pulled from public sources to chart this model and predict the range. To confirm the feasibility of this analysis, the estimated range of 27 m/s was compared with the published range of the Chevy bolt. The range value calculated was within 5% of the published value for the vehicle range.
 
 
[[File:BEV RangeModel.jpg|600px]]
 
The variables in the range equation above can be adjusted to impact the range as shown in the derivatives below. Changes to the range are limited to variables, which are not fixed / constant. Those that cannot be varied include constants such as air density, gravity, drag coefficient, the rolling resistance coefficient, and the vehicle speed (which is controlled by the driver, not directly by design). By varying the mass of the platform, the efficiency of the motor, power electronics, and drive train, and by adjusting the battery capacity (based on pack size), the range of the BEV platform may, in turn be adjusted.
 
[[File:BEV_Derive_mod.png|300px]]
 


It is interesting to note that the architecture and technology selections for the three aircraft (Zephyr, Solar Impulse 2 and E-Fan 2.0) are quite different. While Zephyr uses lithium-sulfur batteries, the other two use the more conventional lithium-ion batteries. Solar Impulse uses the less efficient (but more affordable) single cell silicon-based PV, while Zephyr uses specially manufactured thin film multi-junction cells and so forth.
To examine the impact of these individual variables, the derivatives above were normalized and the values of such were plotted in the tornado chart below. From this it can be seen that reducing vehicle mass has a positive impact on the overall range of the vehicle. Increasing the efficiency of the motor, drive train, and power electronics along with increasing battery capacity leads to an equal increase in range for the BEV platform. The absolute impact on range by increasing the efficiency of the motor, drive train, and power electronics along with increasing battery capacity is greater than the one by reducing the vehicle mass.  


The technical model centers on the E-range and E-endurance equations and compares different aircraft sizing (e.g. wing span, engine power, battery capacity) taking into account aerodynamics, weights and balance, the performance of the aircraft and also its manufacturing cost. It is important to use Multidisciplinary Design Optimization (MDO) when selecting and sizing technologies in order to get the most out of them and compare them fairly (see below).


[[File:Section 7_2.JPG]]
[[File:BEV Tornado2.png|700px]]


==Financial Model==
==Financial Model==
The figure below contains a sample NPV analysis underlying the 2SEA roadmap. It shows the non-recurring cost (NRC) of the product development project (PDP), which includes the R&D expenditures as negative numbers. A ramp up-period of  4 years is planned with a flat revenue plateau (of 400 million per year) and a total program duration of 24 years.


[[File:Section 8.JPG]]
The figure below shows the financial model for the introduction of the all-new BEV platform. The model contains the R&D expenditure over the next 9 years to engineer a platform and three vehicles to support 2 of our 5 critical R&D projects - introduction of the sodium ion battery chemistry, and the modularization of the battery pack. The R&D expenditure is anticipated to improve the vehicles based on the customer's request after the three models are released.
The model also contains the expected revenue over time for vehicle sales, as well as the cost associated with vehicle sales. Our expectation is that we will slowly ramp production over a period of years from 10,000 units per year to 1,016,000 units sold per year, which is the same number of sales of Toyota RAV4 in 2022. The platform is completed in year 3 and model A, B, and C are launched in year 5, 7, and 8. The model charts the discounted revenue and discounted costs over time, which can then be used to calculate yearly discounted free cash flow and our net present value.
 
[[File:BEV_Financial_Model_Figure2.png|600px]]
 
The table below contains the details behind the financial model shown above. As shown in the table, as production ramps, so does our revenue and cost. The three models are sold at the price of $22,500, $31,500, and $40,500 respectively.
The manufacturing cost contains labor and material costs, which are estimated at 8.4% and 57% of the vehicle price.
We expected EBITA to be positive in the 7th year. EBITA per sales is expected more than 14.4% in general, which is the industrial average.
Additionally, working capital per sales is expected to be 13.4%, the industrial average.
 
Also shown in the table below is the time required to recover our investment and manufacturing cost. According to our analyses, it will take approximately 16 years (11 years after the first model is launched) to break even and begin profiting from the production of our all-new BEV platform. This is a high cost of introduction, but we expect that as we scale, we will gain a permanent foothold in the EV market and will see increased profitability in the years following the introduction of this initial BEV platform. The total PV of the project is $14,001 million.


==List of R&T Projects and Prototypes==
[[File:BEV_Financial_Model_Table2.png|1200px]]
In order to select and prioritize R&D (R&T) projects we recommend using the technical and financial models developed as part of the roadmap to rank-order projects based on an objective set of criteria and analysis. The figure below illustrates how technical models are used to make technology project selections, e.g based on the previously stated 2030 target performance and Figure 8-17 (see the Chapter 8 of the text) shows the outcome if none of the three potential projects are selected.


[[File:Section 9.JPG]]
==List of R&D Projects and Prototypes==


A roadmap shows the R&T/R&D projects and demonstrators that have been (completed), are being (active) and could be (proposed) undertaken in order to progress the technology at the component or system level towards the set targets/goal set by the higher or lower-level roadmap. Please add what is essentially a Gantt Chart with milestones.
The choice of R&D projects to undertake is driven by priorities around company strategic drivers as well as key figures of merit. From a strategic perspective, it is important that our R&D projects are aligned to our key strategic drivers of developing a modular set of subsystems, increasing range to customer needs, and integrating with critical external interfaces / infrastructure. Figures of merit that also guide decisions around which R&D investments to make include maximizing battery electric vehicle platform range [km] as well as improving the speed at which battery electric vehicle platforms charge - charging rate [km/min]. The table below lists the R&D projects that we are focused on as investments.  


[[File:Section_9_2.JPG]]
{| class="wikitable sortable" style="margin-left: auto; margin-right: auto; border: none; width: 80%;"
|-
! R&D Project !! Technology Area & TRL!! Description !! Benefits !! Challenges !! Investment Decision
|-
| Sodium-ion battery technology infusion [13] || Battery Technology (TRL 7) || This project will focus on infusing existing technology around sodium ion based battery cells into our existing battery pack module design. ||
* Sodium is far more abundant than the lithium that is used in our battery cells today
* The cost of sodium is significantly less than lithium, allowing us to bring down the cost of our battery pack module
||
* Sodium ions are heavier than lithium and also larger, which could increase the size of the battery cells needed to produce our packs
|| Yes
|-
| Modularization of battery pack design || Platform Modularity (TRL 9) || This project will focus on redefining our battery pack design to make it more modular. As opposed to having one large battery pack, we will create several battery pack modules that can be combined together to meet the battery capacity needs of our different BEV platforms.
||
* Increased ability to service parts of the battery pack in the field when issues occur with individual cells
* Increased scalability of the battery pack to different platforms. We will be able to design our platforms around the size of modules that can scale as capacity needs increase
||
* Introducing battery modules also introduces new interfaces and new potential areas for failure modes
* There is a slight increase in the structural material required to support multiple battery modules, which will impact our platform weight
|| Yes
|-
| Solid state battery technology [14] || Battery Technology (TRL 6) || Development of batteries that utilize a solid electrolyte within our battery cells to carry electrons between battery electrodes, as opposed to the traditional liquid electrolytes that are used in batteries today.
||
* Increased energy density of our battery packs, resulting in increased platform range
* Increased charging speed of BEV platform
* Improved crash safety (e.g., no electrolyte spillage in high speed crash scenarios)
||
* High initial cost as the technology is being introduced
* Manufacturing lines have to be updated to develop this type of battery cell. This may require changes in outsourcing strategies
|| Yes
|-
| Wireless charging [15] || Charging Technology (TRL 5) || Development of charging technology that utilizes electromagnetic fields to transfer electrical current from an in-ground charger to the battery pack of our BEV platform
||
* No high voltage cables required for charging, which reduces the risk of electric shock, overheating, etc.
* Less manual intervention for customers. Charging can begin as soon as a vehicle has parked over a near-field wireless charger
||
* Requires coordination and partnership with infrastructure development projects. Existing infrastructure only supports wired charging
*
|| Yes
|-
| Electric Motor Efficiency Project || Electric Motor (TRL 8)|| This is a proposed project to work on improving electric vehicle motor efficiency
||
* Improved efficiency will result in increased range of the vehicle
* Improved efficiency may also result in improved lifespan of the vehilce
||
* Improvement in efficiency will have minimal overall impact on range considering the effort required to invest in this project
|| No
|-
|Lithium Ferrous Phosphate (LiFePO4 or LFP)  vs Lithium Nickel Manganese Cobalt (Li-NMC) batteries || Battery Technology (TRL 5)|| Build strategy for whether we should invest in LFP, NMC, or both for future battery production
||
* Can secure the production capacity and performance of battery
||
* The technologies are different and require huge CAPEX.
|| Yes
|-
|Second life to Batteries || Battery Technology (TRL 8)|| The majority of Lithium-ion batteries in general are sent to landfill or incinerated and many of the first generation electric vehicles will soon reach their end of life. This project to look propose new ways to utilize these end of the life EV batteries
||
* Technology to sort used batteries into those suitable for a ‘second life’ and those which should be recycled
* Automated methods to dismantle batteries so that they can be recycled more efficiently
||
* No standardized way of packing or labelling batteries
* No safety protocol for the recycling and reusing
|| TBD (may be a better investment for infrastructure organizations)
|-
|}


==Key Publications, Presentations and Patents==
==Key Publications, Presentations and Patents==
A good technology roadmap should contain a comprehensive list of publications, presentations and key patents as shown in Figure 8-19. This includes literature trends, papers published at key conferences and in the trade literature and trade press.


[[File:Section 10 1.JPG]]
The following are a representative set of patents that have contributed to the overall development of Battery Electric Vehicle Platforms. Battery electric vehicle platforms fall under the umbrella CPC code of B60L - "Propulsion of electrically propelled vehicles". Many of the patents describing advances in subcomponent technology, control algorithms, etc. can be found beneath even more detailed CPC codes such as B60L 50/60 ("Electric propulsion with power supplied within the vehicle using power supplied by batteries), B60L 50/51 ("electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells characterized by AC-motors”), and B60L 15/20 ("methods for controlling the traction motor speed of electrically-propelled vehicles").
 
'''High Power Low Voltage Electrified Powertrain'''
*US Patent: 9484852 B2
*Assignee: FCA US LLC
*Inventors: Timmons, Adam, Anand Sathyan, and Marian Mirowski
*Year:2016
*Description: This patent represents a way in which 4 low voltage battery modules could be used to power an electric motor by providing 4 distinct DC voltages to a power inverter that then switches the DC power to AC power to drive an electric motor of 4 or more phases. This represents one potential approach to how a BEV platform could be configured.
*Importance: This patent is relevant to BEV platforms, as it was an early description of what an electrified powertrain/propulsion system architecture would conceptually look like. The patent is relevant to BEV platforms, as it describes the different key modules of an electrified powertrain, such as an electric motor, an independent battery module, a power inverter module, and a controller. These are all critical elements that comprise modern-day BEV platforms.
 
'''Electrified Powertrain With Maximum Performance Mode Control Strategy Using Extended Inverter Limit'''
*US Patent: 2022/1069237
*Assignee: GM Global Technology Operations LLC
*Inventors: Hu, Yiran, Gagas Brent, Kee Kim, James Creehan, and Brian Welchko
*Year:2022
*Description: This patent describes the concept of electrified powertrain maximum performance mode control strategy using extended inverter limit.
*Importance: This patent is relevant to BEV platforms, as it describes an operating scenario for control of the BEV platform. The patent, similar to the one above, does a tremendous job in laying out the critical modules within a BEV. This includes the high voltage battery, power inverter module(s), electric motor(s), DC to DC converters, and more. The patent describes the control strategy to allow the electric motor to enter maximum performance mode, thereby putting out a torque near its own performance limit for a short period of time. Use cases for such a mode are documented as 0-60 tests and other maneuvers. Additionally, the patent calls out the fact that this operating mode is restricted to short periods due to the high load put on the inverter module by the electric motor when it is in maximum performance mode range. Again, this patent represents a potential operating state for BEV platforms.
 
'''System and Method of Controlling Power Distribution From Charging Source to Electric Vehicle'''
*US Patent: 2021/0031643 A1
*Assignee: GM Global Technology Operations LLC
*Inventors: Wang, Yue-Yun, J Brooks, Jun-Mo Kang, and Donald Grimm
*Year:2021
*Description: This patent describes the concept of controlling power distribution from a charging source to electric vehicle, including how the state of charge of the battery is controlled during the charging process.
*Importance: This patent does a very good job of detailing the interface and architecture between charger and the battery being charged, describing how the state of charge of the battery is controlled during the charging process. Again, this patent is relevant to our technology as it represents another operating state of BEV platforms – charging the energy storage mechanism of the BEV.
 
'''Key Publications Pertaining to Battery Electric Vehicle Platforms:'''
 
In addition to the many patents published on concepts that comprise battery electric vehicle platforms, many articles have also been published to describe BEV's, their market progression, and example architectures. Some early examples of articles that reviewed the BEV technology readiness and BEV technology progress are below:
 
*Andwari, Amin, Apostolos Pesiridis, Srithar Rajoo, Ricardo Martinez-Botas, and Vahid Esfahanian.''' “A Review of Battery Electric Vehicle Technology and Readiness Levels.”''' Renewable and Sustainable Energy Reviews 78 (2017): 414–30.
*Sun, Xiaoli, Zhengguo Li, Xiaolin Wang, and Chengjiang Li. ''' “Technology Development of Electric Vehicles: A Review.” ''' Energies 13, no. 1 (2019): 90.
 
Andwari et al (2017) lay out some of the core elements to consider the readiness of BEV’s for commercialization in their article. The article focuses on the potential of different materials to be used within batteries (e.g., Lithium-ion as compared to Lead-acid batteries), as well as the principles behind battery electric vehicle architecture – integration of a battery pack, power electronics, and electric motors. The article also considers charging infrastructure and compares BEV’s to other lower emission vehicles, such as hybrid vehicles and low emission ICE vehicles. Ultimately this article concluded in 2017 that BEV’s would be a critical piece of the transportation sector in the future, as climate and energy fears were on the rise.
 
“Technology development of Electric Vehicles” by Sun et al (2019) considers less of the economic and societal impact of the BEV’s, and rather focuses on the architecture of the battery electric vehicles – assessing current state and future state challenges for each piece of the architecture. The article does a good job in describing a BEV platform based upon the components of a battery pack, battery management system, charging module, power electronics, and electric motor. The article calls out the need for future development in these areas – higher capacity batteries, faster charging technology, and increased reliability of electric motors. But yet again, this article also comments on the bright future for BEV’s in the automotive transportation market


==Technology Strategy Statement==
==Technology Strategy Statement==
A technology roadmap should conclude and be summarized by both a written statement that summarizes the technology strategy coming out of the roadmap as well as a graphic that shows the key R&D investments, targets and a vision for this technology (and associated product or service) over time. For the 2SEA roadmap the statement could read as follows and is displayed in an Arrow Chart:


'''Our target is to develop a new solar-powered and electrically-driven UAV as a HAPS service platform with an Entry-into-Service date of 2030. To achieve the target of an endurance of 500 days and useful payload of 10 kg we will invest in two R&D projects. The first is a flight demonstrator with a first flight by 2027 to demonstrate a full-year aloft (365 days) at an equatorial latitude with a payload of 10 kg. The second project is an accelerated development of Li-S batteries with our partner XYZ with a target lifetime performance of 500 charge-discharge cycles by 2027. This is an enabling technology to reach our 2030 technical and business targets.'''
Our target is to develop the next generation of battery electric vehicle platforms with a target on a fully redefined platform by 2035, but with updates to our existing platforms along the way. Over this time we aim to achieve a range of 1000 km and charging rates of 50 km/min or greater in our platform. To achieve this target we will be focused on 5 projects, including some existing technology infusions. Our first project will be focused on the infusion of sodium-ion battery technology into our existing product portfolio. Our second project will be focused on modularizing our battery pack design to increase our ability to scale the size of battery pack across our three vehicle platforms (sedan, SUV, and heavy-duty platforms). Our third project will be focused on developing solid-state battery technology to reduce the volume of our battery pack to improve packaging in the design, and increase the charging speed of the pack. Our fourth project will be centered on integrating near-field wireless charging technology into our BEV platform. This will allow for faster charging and may enable us to far exceed our target of 50 km/min of charge. Finally, we will also be focused on developing advanced AI-algorithms that will support charging control of our nearfield wireless system as well as advanced battery discharge and torque controls.
 
[[File:BEV Swoosh.jpeg|525px]]
 
==References==
 
[1] Szczesny, Joseph. “GM Targeting Bigger Share of Bev Market, CEO Barra Says.” WardsAuto, June 16, 2022. https://www.wardsauto.com/industry-news/gm-targeting-bigger-share-bev-market-ceo-barra-says.
 
[2] Seabaugh, Christian. “Beyond Plaid: A Quad-Motor Tesla Model S Is Possible.” MotorTrend, June 18, 2021. https://www.motortrend.com/news/tesla-model-s-quad-motor-report/.
 
[3] Oreizi, Darya. “Overview of Electric Vehicle Platforms in 2021.” Charged Future, February 16, 2021. https://www.chargedfuture.com/electric-vehicle-platforms-in-2021/.
 
[4] Kashikar, Gajanan. “Emerging Markets Will Play a Major Role in Hyundai’s Global EV Strategy.” CarWale, April 24, 2021. https://www.carwale.com/news/emerging-markets-will-play-a-major-role-in-hyundais-global-ev-strategy/.
 
[5] Ritchie, Hannah. “The End of Range Anxiety: How Has the Range of Electric Cars Changed over Time?” Sustainability by numbers, February 27, 2023. https://www.sustainabilitybynumbers.com/p/electric-car-range.
 
[6] Bhutada, G. (2022, September 30). Visualizing the range of electric cars vs. gas-powered cars. Visual Capitalist. https://www.visualcapitalist.com/visualizing-the-range-of-electric-cars-vs-gas-powered-cars/
 
[7] 2023 Bloomberg Finance L.P. (2022, December 6). Lithium-ion battery pack prices rise for first time to an average of $151/kwh. BloombergNEF. https://about.bnef.com/blog/lithium-ion-battery-pack-prices-rise-for-first-time-to-an average-of-151-kwh/
 
[8] Cai, Wenlong, Yu-Xing Yao, Gao-Long Zhu, Chong Yan, Li-Li Jiang, Chuanxin He, Jia-Qi Huang, and Qiang Zhang. “A Review on Energy Chemistry of Fast-Charging Anodes.” Chemical Society Reviews 49, no. 12 (June 2020): 3806–33. https://doi.org/10.1039/c9cs00728h.
 
[9] Andwari, Amin, Apostolos Pesiridis, Srithar Rajoo, Ricardo Martinez-Botas, and Vahid Esfahanian. “A Review of Battery Electric Vehicle Technology and Readiness Levels.” Renewable and Sustainable Energy Reviews 78 (2017): 414–30.
 
[10] Sun, Xiaoli, Zhengguo Li, Xiaolin Wang, and Chengjiang Li. “Technology Development of Electric Vehicles: A Review.” Energies 13, no. 1 (2019): 90.
 
[11] “Electric Vehicle Specifications, Electric Car News, EV Comparisons.” EV Specifications. Accessed December 1, 2023. https://www.evspecifications.com/.
 
[12] Grewal, K.S., and P.M. Darnell. “Model-Based EV Range Prediction for Electric Hybrid Vehicles.” Hybrid and Electric Vehicles Conference 2013 (HEVC 2013), 2013. https://doi.org/10.1049/cp.2013.1895.
 
[13] House, Robert. “How Sodium-Ion Batteries Could Make Electric Cars Cheaper.” The Conversation, October 10, 2023. https://theconversation.com/how-sodium-ion-batteries-could-make-electric-cars-cheaper-207342.
 
[14] Kelly, Tim. “Explainer: How Could Solid-State Batteries Improve next-Gen Evs?” Reuters, June 13, 2023. https://www.reuters.com/business/autos-transportation/how-could-solid-state-batteries-improve-next-gen-evs-2023-06-13/.


[[File:Section 11.JPG]]
[15] “Everything You Need to Know about Wireless EV Charging” EV Charging Summit Blog, December 22, 2022. https://evchargingsummit.com/blog/everything-you-need-to-know-about-wireless-ev-charging/.

Latest revision as of 00:57, 5 December 2023

Roadmap Creators: Michael Peters, Hiro Ogasawara, Piyush Kumbhare

Time Stamp: 5 December 2023

Technology Roadmap Sections and Deliverables

  • 2BEV - Battery Electric Vehicle Platforms

The Battery Electric Vehicle (BEV) platform, a level 2 roadmap, represents the critical product/system of the Battery Electric Platform that is integrated within a broader electrified vehicle. The level 1 system above the BEV is the electrified vehicle market segment, which includes other types of electrified vehicles (e.g., FCEV's, PHEV's, etc.) as well as the other vital systems that comprise electrified vehicles (e.g., steer-by-wire systems). Level 3 roadmaps represent critical subsystems within a BEV platform-based electrified vehicle, and level 4 roadmaps would indicate an individual component technology roadmap.

Roadmap Overview

Electrified vehicles are vehicles that utilize electric power (from a variety of different sources, such as batteries or fuel cells) to power an electric motor-based propulsion system. Examples of electrified vehicles that exist on the road today include plug-in hybrid electric vehicles (PHEV), fuel cell electric vehicles (FCV or FCEV) and battery electric vehicles (BEV). Electrified vehicles are an increasingly popular alternative to traditional gas-powered vehicles that generate propulsion through internal combustion engines. Electrified vehicles are one part of a broader ecosystem of solutions being used to combat the evolving problem/challenge of climate change. Electric vehicles help to solve this problem by providing humanity with an alternate mode of transportation that does not produce harmful greenhouse gas emissions.

This roadmap will focus specifically on the battery electric vehicle (BEV) platform. BEV platforms are becoming increasingly popular as consumers seek different options within the electric vehicle market, and manufacturers look for ways to meet this customer demand through the use of modular architectures that multiple different vehicle variants may be built upon. Modular architectures/platforms for battery electric vehicles are typically comprised of a battery pack, on board charging module, integrated power electronics, drive units, and a chassis with a wheelbase. Multiple different vehicle bodies and accompanying features may then be built upon these platforms. Below are examples of BEV platforms being produced today (one by Tesla Motors, and one by General Motors) [1],[2],[3],[4].

Tesla Motors BEV.jpg

Automotive manufacturers today often refer to these types of BEV platform designs as "skateboards", as they are built around the chassis and wheel base and allow for different architectures to be built on top of them. Developing platform and modular designs represents a strategic decision from auto manufacturers, who have historically suffered cost overruns due to the number of different vehicle variants and configurations that are possible in their existing vehicle offering/lineup. Platforming battery electric vehicles reduces the proliferation of possible vehicle variants, reduces manufacturing complexity and the cost to setup manufacturing lines, reduces the cost of vehicles by enabling increased strategic buying patterns, and often results in increased vehicle quality.

GM Ultium BEV 2.jpg Hyundai BEV.jpeg BEV Platform Chassis.jpg

Design Structure Matrix (DSM) Allocation

Our technology of interest, battery electric vehicle platforms, is identified in the DSM below with dark blue highlighting at level 2 (2BEV). Additionally, we also show a tree structure that decomposes into the systems, and subsystems that comprise our level 2 technology. The DSM shows how these critical systems and subsystems interact to comprise the battery electric vehicle platform. For example, we see that a critical subsystem is the level 3 battery pack module, which is color-coded to indicate that it has its own, existing technology roadmap (3ESB - Energy_Storage_via_Battery). The battery pack module (or Energy Storage Battery) is comprised of the battery cells, pack structure, and other subsystems. The battery cells break down into their individual components (anode, cathode, etc.) that generate electrons to conduct electricity. However, we also see the interdependency between the battery pack structure and the high voltage cables, which in turn have a connection to the power inverter module. All this is to say that the interconnected nature of subsystems within a BEV platform critically come together to create the emergence exhibited by a battery electric vehicle.


2BEV DSM v2.png 2BEV Tree v2.png

Roadmap Model using OPM

We provide an Object-Process-Diagram (OPD) of the Battery Electric Vehicle (BEV) Platform in the figure below. This diagrams captures the main object of the technology (Battery Electric Vehicle), the value-generating processes and different instruments associated with their characterization by Figures of Merit (FoM).

The OPD shows that the BEV platform can be decomposed into five main modules - the onboard charger, the battery pack, the engine control unit, the power inverter, and the electric drivetrain. The OPD depicts how these modules interact with one another to generate power at the wheelbase of the BEV platform. In short, the OPD shows that external power can be provided to the BEV platform by charging the battery to a high (up to 100%) state of charge. Once charged, the battery cells within the battery pack module react and create voltage and current that is conducted and then discharged from the battery pack. The engine control unit, which is operated indirectly by a human/operator that is driving the battery electric vehicle, controls the rate of discharge of the battery. The Discharged power from the battery is output as DC power, and is then switched by the power inverter to AC power that turns the electric motor and is transformed into torque. The transmission, which is also controlled by the engine control unit, regulates the torque from low to high and enables the driveshaft to spin, resulting in vehicle acceleration (going from low to high).

BEV OPM v4.jpg

An Object-Process-Language (OPL) description of the roadmap scope is auto-generated and given in OPL_Battery_Electric_Vehicle. It reflects the same content as the previous figure, but in a formal natural language.

Figures of Merit

The table below summarizes the figures of merit used to evaluate battery electric vehicle platform technologies. Some of these figures of merit, such as range and acceleration, are very similar to the figures of merit used to evaluate traditional automotive vehicle. Other figures of merit, such as power storage cost and charge rate, are critical to evaluating the battery pack technology employed within the battery electric vehicle as well as the battery electric vehicle platform itself. Finally, FOM's such as carbon dioxide emissions and kilometers per kilowatt are very specific FOM's to battery electric vehicle platform technologies in totality.

Figure of Merit (FOM) Unit Description
Range [km] The number of miles the vehicle can travel on a single full charge
Acceleration time [s] Time to accelerate to from 0 to 100 kmh (km per hour)
Motor Torque [N.m] Torque produced by the electric vehicle motor
Motor Efficiency [%] Percentage of energy discharged from the battery pack that is converted to mechanical energy
Kilometers per kilowatt [km / kw] The average distance the vehicle travels based upon the amount of energy used
Vehicle charge rate [km/min] The rate at which vehicle range (in km) is added to the BEV platform during charging
Power Storage Cost [$/kWh] Total cost of power storage within a BEV platform (at the battery pack level) in dollars per kilowatt
Carbon Dioxide Emissions [g/km] The total amount of carbon dioxide emissions generated by the vehicle platform per mile driven

Note: Key FOM's are highlighted in bold text

Below are some trends related to the figures of merit listed above. The charts show that the range of battery vehicles has been steadily increasing over the past decade, all while battery prices have rapidly declined. Both of these factors have contributed to increasing adoption of battery electric vehicle platforms, as the cost and performance of these systems continue to rise. Finally, charging trends are improving substantially, as new technology around superchargers enters the market (on both the BEV platform and charging station sides of the interface).

FOM trends 4.jpg

In addition to the figures of merit shown above, some of the key governing equations for battery electric vehicles are shown below.

Input Key Relationship or Governing Equation Output
  • P_out: Power output (mechanical power at driveshaft in watts)
  • P_in: Power input (electrical power into the motor in watts)
ηm = P_out / P_in ηm : motor efficiency (expressed as a %)
  • V_ac : Input voltage (V)
  • I_ac: Input current (A)
  • p_f : power loss coefficient (often efficiency)
  • N_rpm: speed of motor (in rpm)
T = (V_ac* I_ac * p_f ) / ((2π* N_rpm )/60) T = motor torque

Alignment with Company Strategic Drivers

The Automotive industry as a whole is in the midst of significant disruption. The market is shifting as new entrants such as Tesla, Rivian, BYD, and others bring advanced technology and supporting capabilities to a customer base wanting change. As our organization prepares to remain competitive with the likes of Tesla, Rivians, and others, there are three key pillars to our response in the market. First is embracing the transportation transformation. This means that we must realize that our customer base has a desire for an entirely new propulsion option when choosing the vehicle that they purchase. Customers want a vehicle with low or no emissions, and as such we must be prepared to offer this to them. In our case, this will be via a battery electric vehicle. Second is modularity and commonization of key subsystems and components. A key success factor to our ability to deliver new BEV platforms will be ensuring that we have identified where we can modularize major sub-systems and components, so that they can be easily reused across current and future platforms. Our third pillar is interoperability and integration. Our fourth pillar is lifecycle carbon neutrality.As our vehicles go out into the market, they cannot operate on their own any longer. We need to ensure that we have a level of interoperability with new infrastructure being brought online (e.g., charging stations of any brand), and we also must ensure that our products are integrated in a way that allows us to track the performance of vehicles in the field, deliver insights and diagnostics, and provide new features and updates to our customers.


Listed below are the strategic drivers for the company, and the alignment targets of our roadmap with these drivers:

Number Strategic Drivers Alignment targets
1 To develop a battery electric vehicle platform that has an appropriate range for customers seeking to replace their existing internal combustion engine vehicle with a battery-powered electric vehicle. The 2BEV roadmap is aligned to this strategic driver. The battery electric vehicle platform roadmap will target 1000 km as the desired maximum range of the BEV platform that is developed. This is benchmarked off of the top-end range of internal combustion engine vehicles on the market today.
2 To develop a set of battery electric vehicle platforms that will be utilized across all future vehicle production, with optimization of market segment coverage kept in mind and with the ability to scale the platform as necessary to meet the different needs of specific customers. The design of these platforms should minimize CAPEX and OPEX expenditures by allowing for engineering and design focus on a set of modular subsystems across platforms as well as commonization across manufacturing lines used to produce the platforms (reducing the cost of specified equipment). The 2BEV roadmap is aligned to this strategic driver. This roadmap will support this strategic driver by identifying where modularity can be employed across a platform to better enable the optimization of platforms within market segments defined by the organization.
3 To support integration of battery electric vehicle platforms with critical external interfaces to better enable customer experience in areas such as charging, vehicle feature release, etc. The 2BEV roadmap is aligned to this strategic driver. The battery electric vehicle platform roadmap will ensure compliance with the latest SAE charging protocols (e.g., charge port configuration), as well as other industry standards for key functions such as software development and deployment (e.g., AutoSar standards for OTA configuration).
4 To engineer a Battery Electric Vehicle (BEV) platform with minimal carbon emissions throughout the vehicle's lifecycle, ensuring carbon neutrality. The 2BEV roadmap is aligned to this strategic driver. The battery electric vehicle platform roadmap will allocate 5% of its revenue to Research and Technology (R&T) projects to enhance battery efficiency and recyclability. The roadmap will include projects for lifecycle management, such as repurposing old car batteries in various applications.


Positioning of Company vs. Competition

The images and table below show examples of other battery electric vehicle platforms available on the market today (or previously available on the market) along with representative data points for key figures of merit that BEV platforms are evaluated upon (data compiled from evspecifications.com [11]).

BEV Vehicles 2.png
Manufacturer Model Model Year Range [km] Battery Size [kwh] Acceleration Time [s] Vehicle Charge Rate [km/min] Max Torque [N.m] Electric Drive Configuration
General Motors Chevrolet Bolt 2023 416 65 6.5 5.3 360 Single Electric Motor (FWD)
Tesla Model S (performance) 2023 652 100 2.4 21.3 967 Dual Electric Motors
Lucid Air (Touring) 2023 684 94 3.4 21.3 1200 Dual Electric Motors
BMW i5 M60 2024 411 84 3.7 14.5 795 Dual Electric Motors
Subaru Soltera 2023 357 73 6.5 14.6 338 Dual Electric Motors
Nissan Leaf 2011 118 24 9.9 4.6 280 Single Electric Motor (FWD)
Kia Soul 2015 150 30.5 11.2 3.6 285 Single Electric Motor (FWD)
Tesla Model S 2012 426.5 85 5.4 7.6 440 Single Electric Motor (RWD)
General Motors Chevrolet Spark 2014 132 21.3 7.9 4.2 542 Single Electric Motor (FWD)
Hyundai IONIQ 2023 581 77 5.1 25.8 350 Dual Electric Motors
BYD Qin plus EV Pilot Diamond Type 2023 610 72 3.8 20.3 250 Dual Electric Motors

Below is a graph of range [km] vs vehicle charging rate [km/min] for the BEV platforms listed in the table above. This chart illustrates how the pareto front of BEV platform performance has shifted over time as it relates to the key FOM's of range and charging rate. In the bottom left of the chart, there is a cluster of early mass-production BEV platforms such as the Nissan Leaf and the Chevy Spark. In the middle of the chart, we see current-day BEV platforms such as the Chevy Bolt and BMW i5 M60. Towards the upper right side of the chart, we see a high-performing group of current-day BEV platforms in the Tesla Model S (performance), the Lucid Air, and the Hyundai Ioniq. This group of high-performing current-day mass production BEV platforms form the pareto front for existing advancement in BEV platform technology (Data from references [5], [6], and [7]).

BEV Pareto v3.jpg

This chart also shows how specific manufacturers have improved the performance of their technology over time, and what tradeoffs they have made in doing so. For example, General Motors (parent company of the brand Chevrolet) made significant improvements in vehicle range between their 2014 Chevy Spark and their 2023 Chevy Bolt. However, they made only marginal improvements in the performance of vehicle charging rate. On the other hand, Tesla made considerable improvements in both of these areas between their 2012 version of the Tesla Model S and their 2023 Tesla Model S (performance edition). It is also interesting to note that companies like Tesla truly appear to be pushing the Pareto front forward with their latest BEV platforms. They had the most advanced platform on the road when they introduced the model S in 2012, and the latest version of this BEV platform is also near the edge of the pareto front.

Technical Model

In order to assess the feasibility of the technical targets that we have set, at the level of the battery electric vehicle platform roadmap, we have developed a technical model. The purpose of this model is to evaluate the sensitivity of key FOM's (representing progress in technology development) to individual variables that can be adjusted through different architectural and design decisions. As a first step, we have compiled a morphological matrix that represents a set of options available in our future architectural decision-making process:


BEV Matrix.jpg


The morphological matrix for the battery electric vehicle technology represents decisions that can be made around several of the underlying technologies that comprise battery electric vehicle platforms. The selection of different options in these categories represents an impact on individual variables that describe the governing range equation associated with battery electric vehicle performance. Specifically, the variables impacted are those in the parametrized equation representing vehicle driving range. Below is the equation for battery electric vehicle range [equation 1], as well as the decomposition of battery electric vehicle range into underlying, foundational variable parameters [equation 7] (derived from reference [12]). Adjustment to any of the variables shown below will impact the resultant range that a BEV platform may drive.

BEV equations mod2.png

BEV Variables.jpg

The variables and equations above can then be used to develop a model for battery electric vehicle range based upon the constant speed (v) that the vehicle is driving at. Below is a graph of that model for an example BEV - the 2023 Chevy Bolt. Data for the Chevy bolt was pulled from public sources to chart this model and predict the range. To confirm the feasibility of this analysis, the estimated range of 27 m/s was compared with the published range of the Chevy bolt. The range value calculated was within 5% of the published value for the vehicle range.


BEV RangeModel.jpg

The variables in the range equation above can be adjusted to impact the range as shown in the derivatives below. Changes to the range are limited to variables, which are not fixed / constant. Those that cannot be varied include constants such as air density, gravity, drag coefficient, the rolling resistance coefficient, and the vehicle speed (which is controlled by the driver, not directly by design). By varying the mass of the platform, the efficiency of the motor, power electronics, and drive train, and by adjusting the battery capacity (based on pack size), the range of the BEV platform may, in turn be adjusted.

BEV Derive mod.png


To examine the impact of these individual variables, the derivatives above were normalized and the values of such were plotted in the tornado chart below. From this it can be seen that reducing vehicle mass has a positive impact on the overall range of the vehicle. Increasing the efficiency of the motor, drive train, and power electronics along with increasing battery capacity leads to an equal increase in range for the BEV platform. The absolute impact on range by increasing the efficiency of the motor, drive train, and power electronics along with increasing battery capacity is greater than the one by reducing the vehicle mass.


BEV Tornado2.png

Financial Model

The figure below shows the financial model for the introduction of the all-new BEV platform. The model contains the R&D expenditure over the next 9 years to engineer a platform and three vehicles to support 2 of our 5 critical R&D projects - introduction of the sodium ion battery chemistry, and the modularization of the battery pack. The R&D expenditure is anticipated to improve the vehicles based on the customer's request after the three models are released. The model also contains the expected revenue over time for vehicle sales, as well as the cost associated with vehicle sales. Our expectation is that we will slowly ramp production over a period of years from 10,000 units per year to 1,016,000 units sold per year, which is the same number of sales of Toyota RAV4 in 2022. The platform is completed in year 3 and model A, B, and C are launched in year 5, 7, and 8. The model charts the discounted revenue and discounted costs over time, which can then be used to calculate yearly discounted free cash flow and our net present value.

BEV Financial Model Figure2.png

The table below contains the details behind the financial model shown above. As shown in the table, as production ramps, so does our revenue and cost. The three models are sold at the price of $22,500, $31,500, and $40,500 respectively. The manufacturing cost contains labor and material costs, which are estimated at 8.4% and 57% of the vehicle price. We expected EBITA to be positive in the 7th year. EBITA per sales is expected more than 14.4% in general, which is the industrial average. Additionally, working capital per sales is expected to be 13.4%, the industrial average.

Also shown in the table below is the time required to recover our investment and manufacturing cost. According to our analyses, it will take approximately 16 years (11 years after the first model is launched) to break even and begin profiting from the production of our all-new BEV platform. This is a high cost of introduction, but we expect that as we scale, we will gain a permanent foothold in the EV market and will see increased profitability in the years following the introduction of this initial BEV platform. The total PV of the project is $14,001 million.

BEV Financial Model Table2.png

List of R&D Projects and Prototypes

The choice of R&D projects to undertake is driven by priorities around company strategic drivers as well as key figures of merit. From a strategic perspective, it is important that our R&D projects are aligned to our key strategic drivers of developing a modular set of subsystems, increasing range to customer needs, and integrating with critical external interfaces / infrastructure. Figures of merit that also guide decisions around which R&D investments to make include maximizing battery electric vehicle platform range [km] as well as improving the speed at which battery electric vehicle platforms charge - charging rate [km/min]. The table below lists the R&D projects that we are focused on as investments.

R&D Project Technology Area & TRL Description Benefits Challenges Investment Decision
Sodium-ion battery technology infusion [13] Battery Technology (TRL 7) This project will focus on infusing existing technology around sodium ion based battery cells into our existing battery pack module design.
  • Sodium is far more abundant than the lithium that is used in our battery cells today
  • The cost of sodium is significantly less than lithium, allowing us to bring down the cost of our battery pack module
  • Sodium ions are heavier than lithium and also larger, which could increase the size of the battery cells needed to produce our packs
Yes
Modularization of battery pack design Platform Modularity (TRL 9) This project will focus on redefining our battery pack design to make it more modular. As opposed to having one large battery pack, we will create several battery pack modules that can be combined together to meet the battery capacity needs of our different BEV platforms.
  • Increased ability to service parts of the battery pack in the field when issues occur with individual cells
  • Increased scalability of the battery pack to different platforms. We will be able to design our platforms around the size of modules that can scale as capacity needs increase
  • Introducing battery modules also introduces new interfaces and new potential areas for failure modes
  • There is a slight increase in the structural material required to support multiple battery modules, which will impact our platform weight
Yes
Solid state battery technology [14] Battery Technology (TRL 6) Development of batteries that utilize a solid electrolyte within our battery cells to carry electrons between battery electrodes, as opposed to the traditional liquid electrolytes that are used in batteries today.
  • Increased energy density of our battery packs, resulting in increased platform range
  • Increased charging speed of BEV platform
  • Improved crash safety (e.g., no electrolyte spillage in high speed crash scenarios)
  • High initial cost as the technology is being introduced
  • Manufacturing lines have to be updated to develop this type of battery cell. This may require changes in outsourcing strategies
Yes
Wireless charging [15] Charging Technology (TRL 5) Development of charging technology that utilizes electromagnetic fields to transfer electrical current from an in-ground charger to the battery pack of our BEV platform
  • No high voltage cables required for charging, which reduces the risk of electric shock, overheating, etc.
  • Less manual intervention for customers. Charging can begin as soon as a vehicle has parked over a near-field wireless charger
  • Requires coordination and partnership with infrastructure development projects. Existing infrastructure only supports wired charging
Yes
Electric Motor Efficiency Project Electric Motor (TRL 8) This is a proposed project to work on improving electric vehicle motor efficiency
  • Improved efficiency will result in increased range of the vehicle
  • Improved efficiency may also result in improved lifespan of the vehilce
  • Improvement in efficiency will have minimal overall impact on range considering the effort required to invest in this project
No
Lithium Ferrous Phosphate (LiFePO4 or LFP) vs Lithium Nickel Manganese Cobalt (Li-NMC) batteries Battery Technology (TRL 5) Build strategy for whether we should invest in LFP, NMC, or both for future battery production
  • Can secure the production capacity and performance of battery
  • The technologies are different and require huge CAPEX.
Yes
Second life to Batteries Battery Technology (TRL 8) The majority of Lithium-ion batteries in general are sent to landfill or incinerated and many of the first generation electric vehicles will soon reach their end of life. This project to look propose new ways to utilize these end of the life EV batteries
  • Technology to sort used batteries into those suitable for a ‘second life’ and those which should be recycled
  • Automated methods to dismantle batteries so that they can be recycled more efficiently
  • No standardized way of packing or labelling batteries
  • No safety protocol for the recycling and reusing
TBD (may be a better investment for infrastructure organizations)

Key Publications, Presentations and Patents

The following are a representative set of patents that have contributed to the overall development of Battery Electric Vehicle Platforms. Battery electric vehicle platforms fall under the umbrella CPC code of B60L - "Propulsion of electrically propelled vehicles". Many of the patents describing advances in subcomponent technology, control algorithms, etc. can be found beneath even more detailed CPC codes such as B60L 50/60 ("Electric propulsion with power supplied within the vehicle using power supplied by batteries), B60L 50/51 ("electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells characterized by AC-motors”), and B60L 15/20 ("methods for controlling the traction motor speed of electrically-propelled vehicles").

High Power Low Voltage Electrified Powertrain

  • US Patent: 9484852 B2
  • Assignee: FCA US LLC
  • Inventors: Timmons, Adam, Anand Sathyan, and Marian Mirowski
  • Year:2016
  • Description: This patent represents a way in which 4 low voltage battery modules could be used to power an electric motor by providing 4 distinct DC voltages to a power inverter that then switches the DC power to AC power to drive an electric motor of 4 or more phases. This represents one potential approach to how a BEV platform could be configured.
  • Importance: This patent is relevant to BEV platforms, as it was an early description of what an electrified powertrain/propulsion system architecture would conceptually look like. The patent is relevant to BEV platforms, as it describes the different key modules of an electrified powertrain, such as an electric motor, an independent battery module, a power inverter module, and a controller. These are all critical elements that comprise modern-day BEV platforms.

Electrified Powertrain With Maximum Performance Mode Control Strategy Using Extended Inverter Limit

  • US Patent: 2022/1069237
  • Assignee: GM Global Technology Operations LLC
  • Inventors: Hu, Yiran, Gagas Brent, Kee Kim, James Creehan, and Brian Welchko
  • Year:2022
  • Description: This patent describes the concept of electrified powertrain maximum performance mode control strategy using extended inverter limit.
  • Importance: This patent is relevant to BEV platforms, as it describes an operating scenario for control of the BEV platform. The patent, similar to the one above, does a tremendous job in laying out the critical modules within a BEV. This includes the high voltage battery, power inverter module(s), electric motor(s), DC to DC converters, and more. The patent describes the control strategy to allow the electric motor to enter maximum performance mode, thereby putting out a torque near its own performance limit for a short period of time. Use cases for such a mode are documented as 0-60 tests and other maneuvers. Additionally, the patent calls out the fact that this operating mode is restricted to short periods due to the high load put on the inverter module by the electric motor when it is in maximum performance mode range. Again, this patent represents a potential operating state for BEV platforms.

System and Method of Controlling Power Distribution From Charging Source to Electric Vehicle

  • US Patent: 2021/0031643 A1
  • Assignee: GM Global Technology Operations LLC
  • Inventors: Wang, Yue-Yun, J Brooks, Jun-Mo Kang, and Donald Grimm
  • Year:2021
  • Description: This patent describes the concept of controlling power distribution from a charging source to electric vehicle, including how the state of charge of the battery is controlled during the charging process.
  • Importance: This patent does a very good job of detailing the interface and architecture between charger and the battery being charged, describing how the state of charge of the battery is controlled during the charging process. Again, this patent is relevant to our technology as it represents another operating state of BEV platforms – charging the energy storage mechanism of the BEV.

Key Publications Pertaining to Battery Electric Vehicle Platforms:

In addition to the many patents published on concepts that comprise battery electric vehicle platforms, many articles have also been published to describe BEV's, their market progression, and example architectures. Some early examples of articles that reviewed the BEV technology readiness and BEV technology progress are below:

  • Andwari, Amin, Apostolos Pesiridis, Srithar Rajoo, Ricardo Martinez-Botas, and Vahid Esfahanian. “A Review of Battery Electric Vehicle Technology and Readiness Levels.” Renewable and Sustainable Energy Reviews 78 (2017): 414–30.
  • Sun, Xiaoli, Zhengguo Li, Xiaolin Wang, and Chengjiang Li. “Technology Development of Electric Vehicles: A Review.” Energies 13, no. 1 (2019): 90.

Andwari et al (2017) lay out some of the core elements to consider the readiness of BEV’s for commercialization in their article. The article focuses on the potential of different materials to be used within batteries (e.g., Lithium-ion as compared to Lead-acid batteries), as well as the principles behind battery electric vehicle architecture – integration of a battery pack, power electronics, and electric motors. The article also considers charging infrastructure and compares BEV’s to other lower emission vehicles, such as hybrid vehicles and low emission ICE vehicles. Ultimately this article concluded in 2017 that BEV’s would be a critical piece of the transportation sector in the future, as climate and energy fears were on the rise.

“Technology development of Electric Vehicles” by Sun et al (2019) considers less of the economic and societal impact of the BEV’s, and rather focuses on the architecture of the battery electric vehicles – assessing current state and future state challenges for each piece of the architecture. The article does a good job in describing a BEV platform based upon the components of a battery pack, battery management system, charging module, power electronics, and electric motor. The article calls out the need for future development in these areas – higher capacity batteries, faster charging technology, and increased reliability of electric motors. But yet again, this article also comments on the bright future for BEV’s in the automotive transportation market

Technology Strategy Statement

Our target is to develop the next generation of battery electric vehicle platforms with a target on a fully redefined platform by 2035, but with updates to our existing platforms along the way. Over this time we aim to achieve a range of 1000 km and charging rates of 50 km/min or greater in our platform. To achieve this target we will be focused on 5 projects, including some existing technology infusions. Our first project will be focused on the infusion of sodium-ion battery technology into our existing product portfolio. Our second project will be focused on modularizing our battery pack design to increase our ability to scale the size of battery pack across our three vehicle platforms (sedan, SUV, and heavy-duty platforms). Our third project will be focused on developing solid-state battery technology to reduce the volume of our battery pack to improve packaging in the design, and increase the charging speed of the pack. Our fourth project will be centered on integrating near-field wireless charging technology into our BEV platform. This will allow for faster charging and may enable us to far exceed our target of 50 km/min of charge. Finally, we will also be focused on developing advanced AI-algorithms that will support charging control of our nearfield wireless system as well as advanced battery discharge and torque controls.

BEV Swoosh.jpeg

References

[1] Szczesny, Joseph. “GM Targeting Bigger Share of Bev Market, CEO Barra Says.” WardsAuto, June 16, 2022. https://www.wardsauto.com/industry-news/gm-targeting-bigger-share-bev-market-ceo-barra-says.

[2] Seabaugh, Christian. “Beyond Plaid: A Quad-Motor Tesla Model S Is Possible.” MotorTrend, June 18, 2021. https://www.motortrend.com/news/tesla-model-s-quad-motor-report/.

[3] Oreizi, Darya. “Overview of Electric Vehicle Platforms in 2021.” Charged Future, February 16, 2021. https://www.chargedfuture.com/electric-vehicle-platforms-in-2021/.

[4] Kashikar, Gajanan. “Emerging Markets Will Play a Major Role in Hyundai’s Global EV Strategy.” CarWale, April 24, 2021. https://www.carwale.com/news/emerging-markets-will-play-a-major-role-in-hyundais-global-ev-strategy/.

[5] Ritchie, Hannah. “The End of Range Anxiety: How Has the Range of Electric Cars Changed over Time?” Sustainability by numbers, February 27, 2023. https://www.sustainabilitybynumbers.com/p/electric-car-range.

[6] Bhutada, G. (2022, September 30). Visualizing the range of electric cars vs. gas-powered cars. Visual Capitalist. https://www.visualcapitalist.com/visualizing-the-range-of-electric-cars-vs-gas-powered-cars/

[7] 2023 Bloomberg Finance L.P. (2022, December 6). Lithium-ion battery pack prices rise for first time to an average of $151/kwh. BloombergNEF. https://about.bnef.com/blog/lithium-ion-battery-pack-prices-rise-for-first-time-to-an average-of-151-kwh/

[8] Cai, Wenlong, Yu-Xing Yao, Gao-Long Zhu, Chong Yan, Li-Li Jiang, Chuanxin He, Jia-Qi Huang, and Qiang Zhang. “A Review on Energy Chemistry of Fast-Charging Anodes.” Chemical Society Reviews 49, no. 12 (June 2020): 3806–33. https://doi.org/10.1039/c9cs00728h.

[9] Andwari, Amin, Apostolos Pesiridis, Srithar Rajoo, Ricardo Martinez-Botas, and Vahid Esfahanian. “A Review of Battery Electric Vehicle Technology and Readiness Levels.” Renewable and Sustainable Energy Reviews 78 (2017): 414–30.

[10] Sun, Xiaoli, Zhengguo Li, Xiaolin Wang, and Chengjiang Li. “Technology Development of Electric Vehicles: A Review.” Energies 13, no. 1 (2019): 90.

[11] “Electric Vehicle Specifications, Electric Car News, EV Comparisons.” EV Specifications. Accessed December 1, 2023. https://www.evspecifications.com/.

[12] Grewal, K.S., and P.M. Darnell. “Model-Based EV Range Prediction for Electric Hybrid Vehicles.” Hybrid and Electric Vehicles Conference 2013 (HEVC 2013), 2013. https://doi.org/10.1049/cp.2013.1895.

[13] House, Robert. “How Sodium-Ion Batteries Could Make Electric Cars Cheaper.” The Conversation, October 10, 2023. https://theconversation.com/how-sodium-ion-batteries-could-make-electric-cars-cheaper-207342.

[14] Kelly, Tim. “Explainer: How Could Solid-State Batteries Improve next-Gen Evs?” Reuters, June 13, 2023. https://www.reuters.com/business/autos-transportation/how-could-solid-state-batteries-improve-next-gen-evs-2023-06-13/.

[15] “Everything You Need to Know about Wireless EV Charging” EV Charging Summit Blog, December 22, 2022. https://evchargingsummit.com/blog/everything-you-need-to-know-about-wireless-ev-charging/.