ISC Fault Diagnosis and Security Monitoring for Lithium Battery Based on Voltage Variance

With the burgeoning popularity of new energy vehicles, lithium batteries have emerged as vital power sources for contemporary electric vehicles, attributed to their high-power density and minimal environmental impact. Concurrently, the widespread applications of electric vehicles bring a series of safety concerns, notably the internal short circuit fault within batteries. The internal short circuit fault is often elusive, making detection challenging and leading to severe accidents due to its concealment and stochastic nature. To address this challenge, the paper proposes a method for diagnosing batteries internal short circuit faults. Initially, the complexity of the voltage matrix is qualitatively analyzed by calculating the maximum eigenvalue occupancy across various covariance matrices. Subsequently, the local features of voltage variance in neighboring batteries are leveraged to pinpoint the fault location and occurrence moment. The simulation results ultimately indicate the high efficacy of the proposed method in localizing and temporally detecting internal short circuit faults within battery packs.