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Current Trends for State-of-Charge (SoC) Estimation in Lithium-Ion Battery Electric Vehicles

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  • Ingvild B. Espedal

    (Department of Energy and Process Engineering & ENERSENSE, NTNU, 7491 Trondheim, Norway)

  • Asanthi Jinasena

    (Department of Energy and Process Engineering & ENERSENSE, NTNU, 7491 Trondheim, Norway)

  • Odne S. Burheim

    (Department of Energy and Process Engineering & ENERSENSE, NTNU, 7491 Trondheim, Norway)

  • Jacob J. Lamb

    (Department of Energy and Process Engineering & ENERSENSE, NTNU, 7491 Trondheim, Norway
    Department of Electronic Systems & ENERSENSE, NTNU, 7491 Trondheim, Norway)

Abstract

Energy storage systems (ESSs) are critically important for the future of electric vehicles. Despite this, the safety and management of ESSs require improvement. Battery management systems (BMSs) are vital components in ESS systems for Lithium-ion batteries (LIBs). One parameter that is included in the BMS is the state-of-charge (SoC) of the battery. SoC has become an active research area in recent years for battery electric vehicle (BEV) LIBs, yet there are some challenges: the LIB configuration is nonlinear, making it hard to model correctly; it is difficult to assess internal environments of a LIB (and this can be different in laboratory conditions compared to real-world conditions); and these discrepancies can lead to raising the instability of the LIB. Therefore, further advancement is required in order to have higher accuracy in SoC estimation in BEV LIBs. SoC estimation is a key BMS feature, and precise modeling and state estimation will improve stable operation. This review discusses current methods use in BEV LIB SoC modelling and estimation. The review culminates in a brief discussion of challenges in BEV LIB SoC prediction analysis.

Suggested Citation

  • Ingvild B. Espedal & Asanthi Jinasena & Odne S. Burheim & Jacob J. Lamb, 2021. "Current Trends for State-of-Charge (SoC) Estimation in Lithium-Ion Battery Electric Vehicles," Energies, MDPI, vol. 14(11), pages 1-24, June.
    • Handle: RePEc:gam:jeners:v:14:y:2021:i:11:p:3284-:d:568712
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    References listed on IDEAS

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    5. Stefano Leonori & Luca Baldini & Antonello Rizzi & Fabio Massimo Frattale Mascioli, 2021. "A Physically Inspired Equivalent Neural Network Circuit Model for SoC Estimation of Electrochemical Cells," Energies, MDPI, vol. 14(21), pages 1-29, November.
    6. Takyi-Aninakwa, Paul & Wang, Shunli & Zhang, Hongying & Yang, Xiao & Fernandez, Carlos, 2023. "A hybrid probabilistic correction model for the state of charge estimation of lithium-ion batteries considering dynamic currents and temperatures," Energy, Elsevier, vol. 273(C).
    7. Takyi-Aninakwa, Paul & Wang, Shunli & Zhang, Hongying & Li, Huan & Xu, Wenhua & Fernandez, Carlos, 2022. "An optimized relevant long short-term memory-squared gain extended Kalman filter for the state of charge estimation of lithium-ion batteries," Energy, Elsevier, vol. 260(C).
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