Dynamic Equivalent Circuit Model to Estimate State-of-Health of Lithium-Ion Batteries

Lithium-ion (Li-ion) batteries have increasingly been used in diverse applications. Accurate estimation of the state health (SOH) Li-ion is vital for all stakeholders and critical various applications such as electric vehicles (EVs). The electrical equivalent circuit (EEC) 2-RC model often to battery operation but has not capture degradation cells over time. This paper uses battery. proposed only time-dependent also captures effect temperature on degradation. approach estimates SOH accurately considerably flexible different chemistry. We further generalize an N-RC evaluate compare (2-RC) with 1-RC model, through numerical results, we show that outperforms reduces computational cost significantly. Similarly, 3-RC higher-order circuits. can dynamics better specific smaller orders polynomial (associated Arrhenius equation) when compared reduced (up 60%) root mean square error (RMSE). Lastly, average testing RMSE 52.4%.