Real-time SOH Estimation Algorithm Based on Coulomb Counting and Constant Voltage Charging Time Reset

This paper proposes an algorithm that estimates the state-of-health (SOH) of lithium-ion batteries in realtime on the basis of current integration and constant voltage charging time. The proposed algorithm estimates the SOH on the basis of the total cycle and current capacity according to battery manufacturing and the current capacity accumulated in real time. The SOH estimation accuracy was improved by re-estimating the estimated SOH on the basis of the SOH value compared with the constant voltage charging time when constant voltage charging occurs. The algorithm is verified through an aging experiment using LiFePO4 batteries.