515

Levelized Cost of Storage Framework for Solid-State Batteries in 400V/800V Electric Vehicle Powertrains

G. S. Quansah(1), O. Oñederra(1), G. Saldaña(1), M. González-Pérez(2) and I. Zamora(1)

1. Department of Electrical Engineering, Engineering School of Bilbao, University of the Basque Country, Bilbao, Spain

2. Department of Electrical Engineering, Engineering School of Gipuzkoa, University of the Basque Country, Eibar, Spain

2026-02-15

Electric Vehicle (EV) manufacturers are adopting a range of powertrain architectures, with voltage systems ranging from
400V to 800V. The voltage ranges improves the efficiency and performance of EV powertrains. This improvement transforms EVs into more than just transportation systems. They also integrate the EVs as critical distributed energy storage units, and helps in grid stability, and energy load balancing through vehicle-to-grid (V2G) integration. Solid-state batteries (SSBs) represent an advanced energy storage technology, which enable EVs to operate efficiently at higher voltage configurations. To evaluate their feasibility and cost-effectiveness, the Levelized Cost of Storage (LCOS) serves as a critical metric. A low LCOS indicates improved cost-efficiency, and is achieved through careful optimization of capital expenditure (CapEx), reduced operational expenditure (OpEx), and minimized energy losses, during operation. In contrast, a high LCOS, exposes inefficiencies in system integration, lifecycle design, or operational management. This paper develops a detailed LCOS framework, for the deployment of SSBs in 400V and 800V EV powertrain topologies. The model uses mathematical formulations across various automotive platforms. Simulation results show that 800V
EVs have a lower LCOS, compared to 400V systems. These findings support the economic and technical viability of SSBs in high-voltage EV powertrains.

Key words: Electric Vehicle, Solid State Battery, Levelized Cost of Storage,

[1] A. Alkhalidi, M. K. Khawaja, and S. M. Ismail, “Solid-state batteries, their future in the energy storage and electric
vehicles market,” Sci. Talks, vol. 11, no. July, p. 100382, 2024, doi: 10.1016/j.sctalk.2024.100382.

[2] Toyota Company, “Solid State Batteries,” 2021. https://www.toyota.ie/company/news/2021/solid-statebatteries.

[3] Toyota Cleveland Heights, “How Toyota’s Solid-State Battery Will Change the Future of Electric Cars,” 2025.
https://www.toyotaclevelandheights.com/how-toyotassolid-state-battery-will-change-the-future-of-electric-cars/.

[4] Honda, “The next-generation batteries that will change EVs toward a carbon-neutral society! Honda’s research on an
all-solid-state battery.,” 2025. https://global.honda/en/tech/All-solidstate_battery_technology/.

[5] Livescience, “Honda promises solid-state batteries that could double EV range to 620 miles by 2030,” 2025,
[Online]. Available: https://www.livescience.com/technology/electricvehicles/honda-promises-solid-state-batteries-that-coulddouble-ev-range-to-620-miles-by-2030.

[6] IAA Mobility, “BMW presents a revolutionary battery for electric vehicles: The game changer in electromobility?,”
2024. https://www.iaamobility.com/en/newsroom/news/e-vehicle/bmwpresents-a-revolutionary-battery-for-electric-vehicles.

[7] BMW Group, “BMW Group and Solid Power deepen Joint Development Partnership,” 2023. https://www.press.bmwgroup.com/global/article/detail/T0407744EN/bmw-group-and-solid-power-deepen-jointdevelopment-partnership?language=en.

[8] Nissan Motor Corporation, “All-solid-state batteries,” 2024. https://www.nissanglobal.com/en/innovation/technology/ archive/ASSB/.

[9] Volkswagen Group, “PowerCo and QuantumScape Announce Landmark Agreement to Industrialize Solid-
State Batteries,” 2024, [Online]. Available: https://www.volkswagen-group.com/en/pressreleases/powerco-and-quantumscape-announce-landmarkagreement-to-industrialize-solid-state-batteries-18494.

[10] P. B. Bobba, L. S. H. Yerraguntla, S. Pisini, H. P. Bhupathi, D. Srinivas, and M. M. Hassan, “Performance analysis of
solid-state batteries in Electric vehicle applications,” E3S Web Conf., vol. 552, pp. 1–13, 2024, doi:
10.1051/e3sconf/202455201149.

[11] Y. Xu, J. Pei, L. Cui, P. Liu, and T. Ma, “The Levelized Cost of Storage of Electrochemical Energy Storage
Technologies in China,” Front. Energy Res., vol. 10, no. June, pp. 1–16, 2022, doi: 10.3389/fenrg.2022.873800.

[12] FutureBattery Lab, “Solid state batteries at a glance.” https://futurebatterylab.com/solid-state-batteries-at-aglance/.

[13] K. E. Rodby, T. J. Carney, Y. Ashraf Gandomi, J. L. Barton, R. M. Darling, and F. R. Brushett, “Assessing the
levelized cost of vanadium redox flow batteries with capacity fade and rebalancing,” J. Power Sources, vol. 460, 2020, doi: 10.1016/j.jpowsour.2020.227958.

[14] O. Schmidt, S. Melchior, A. Hawkes, and I. Staffell, “Projecting the Future Levelized Cost of Electricity Storage Technologies,” Joule, vol. 3, no. 1, pp. 81–100, 2019, doi: 10.1016/j.joule.2018.12.008.

[15] T. Steckel, A. Kendall, and H. Ambrose, “Applying levelized cost of storage methodology to utility-scale second-life lithium-ion battery energy storage systems,” Appl. Energy, vol. 300, 2021, doi: 10.1016/j.apenergy.2021.117309.