Abstract: In recent years, the localization rate of electronic components has been continuously improved, and higher standards have been put forward for their reliability. Against this backdrop, this paper takes a self-developed domestic energy storage device as the research object. Based on existing research on fault detection and protection technologies, this paper characterizes the failure modes of critical components such as IGBTs, voltage sensors and main control chips under practical operating conditions, and develops corresponding fault-tolerant and protection mechanisms, which act as a critical guarantee for the highly reliable operation of the self-developed domestic energy storage device. Finally, this paper summarizes the deficiencies and limitations of this research and prospects future research directions.