Analysis of Fault Diagnosis and Safety Protection Technologies for New Energy Vehicle Battery Systems

Abstract

With the rapid growth in the number of new energy vehicles on the road, the safety and reliability of lithium-ion power battery systems have become a major focus of attention. This paper systematically analyzes typical failure modes in power battery systems, summarizes their multi-source, coupled, and progressive characteristics, and identifies internal short circuits as the core factor triggering thermal runaway. Building on this, the paper reviews three categories of fault diagnosis methods-based on parameter monitoring, mathematical-physical models, and data-driven approaches-and compares their respective application scenarios and limitations. It then elaborates on comprehensive protection strategies covering graded early warning, thermal runaway suppression, high-voltage electrical safety, and regulatory compliance. Finally, the paper discusses technical bottlenecks such as the trade-off between diagnostic real-time performance and accuracy, a0s well as the scarcity of fault samples, and outlines future development directions including vehicle-cloud collaboration and digital twins. This paper aims to provide a technical reference for fault diagnosis and safety protection in power battery systems.