Study on the Impedance Increase Fault of Parallel Connected Batteries Based on Simscape Model Simulation

This paper presents a simple and intuitive method for fault simulation of parallel connected batteries using Simscape. The proposed method can simulate voltage, current and SOC (sate of charge) of each cell, the parameters of the simulation model are obtained through the HPPC (Hybrid Pulse Power Characteristic) test. For fault analysis, parallel connected batteries are equivalent to a single battery using online parameter identification. The fault conditions, such as pure ohmic internal resistance increase and available capacity decrease, are simulated. Parallel connected batteries´ voltage, cell´s SOC, parallel connected batteries´ identified ohmic resistance and parallel connected batteries´ identified open circuit voltage are analyzed through contrastive analysis between different fault conditions. The effect of different fault conditions on voltage inconsistency and SOC inconsistency are compared through simulation.