State-of-Charge and State-of-Energy Estimation for Lithium-ion Batteries Using Sliding-Mode Observers

Based on the equivalent circuit model of a lithium-ion battery, this paper proposes a sliding mode observer for its State-of-Charge (SoC) estimation. In order to further estimate the State-of-Energy (SoE) of lithium-ion batteries, a real-time SoE estimation algorithm is established using the super-twisting technique. The Lyapunov stability theory is utilized to prove the proposed SoC and SoE estimation algorithms. Finally, the experimental data of Dynamic Stress Test (DST) and Federal Urban Driving Schedule (FUDS) test verify the accuracy and robustness of the proposed SoC and SoE estimation algorithms.