Investigation on Early-stage Internal Short Circuit Identification for Power Battery Pack

Abstract

The spontaneous internal short circuit is a very important way for the thermal runaway of lithium-ion battery. Identification of the internal short circuit accurately and in time during the working process is critical for the safety of lithium-ion battery. In this study, a modified algorithm for the early-stage internal short circuit identification is investigated. This method is based on the mean-difference model and the recursive least square algorithm. An equivalent experiment is setup to validate the feasibility of this method for the identification of early-stage internal short circuit. The results indicate that this method can identify the internal short circuit only when the SOC is very low. For ordinary operation conditions of the power battery pack, this method is not suitable for early-stage internal short circuit identification. Keywords—lithium-ion battery; internal short circuit; identification algorithm; mean-difference model; early stage