Multi-dimensional fault analysis and diagnostic techniques for li-ion batteries in EVs. A review

Electric vehicle (EV) batteries are critical energy storage units, and ensuring their safety is of utmost importance. Faults in lithium-ion (Li-ion) EV batteries can arise from various mechanical, electrical, thermal, and chemical factors, occurring at different battery hierarchical levels, from individual cells to complete battery packs. The complex interplay of these faults, along with their overlapping symptoms, makes early detection and precise diagnosis challenging. This review provides a multidimensional analysis of fault mechanisms in Li-ion EV batteries, systematically classifying faults at the cell, module, and pack levels while examining their causes, effects, and propagation pathways. Additionally, it explores advanced fault diagnostic techniques, including model-based, data-driven, statistical, and knowledge-based methods, mapping them to specific fault mechanisms and battery hierarchical levels. By integrating fault analysis with diagnostic methodologies, the study enhances the safety and security of battery storage systems and contributes to the advancement of new energy vehicle technologies.