State of health estimation based on constant current charging profiles

Achieving accurate estimation of battery state of health (SOH) is of great significance for improving the battery management system of electric vehicles. In this paper, an indirect health indicator (HI) for the SOH estimation of lithium-ion batteries based on the constant current charging curves is introduced. A linear model is developed to express the relationship between the HI and Box-Cox transformed SOH. The simulation results on various discharge condition and even different types of batteries show that the proposed HI and linear model can accurately estimate the battery SOH and show excellent generalization performance.