Research on Internal Short-circuit Fault Diagnosis Based on Correlation Coefficient Method

Battery energy storage systems are typically composed of lithium-ion battery packs. Among many battery faults, internal short-circuit faults pose the most serious hazards, and diagnosing and locating such faults has attracted widespread attention. This paper focuses on battery modules and adopts an improved correlation coefficient method. By reducing computational complexity through a sliding time window, it compares the correlation coefficients of battery voltages collected by adjacent sensors. Based on the steep drop characteristics of correlation coefficients caused by the consistency difference between faulty battery voltages and normal battery voltages, this paper diagnoses and locates internal short-circuit faults within battery packs. Experimental results show that this method can effectively locate and diagnose faulty batteries based on correlation coefficient threshold judgments.