Abstract: In order to enhance the emergency power supply guarantee capability of ports and solve the problems of traditional diesel generators, a mobile emergency power supply guarantee system based on energy storage technology has been researched and established. Through modular design, the energy storage system, battery management system, power conversion system, and energy management system are integrated into the container truck. Lithium iron phosphate batteries are used as the core energy storage components, and the energy storage configuration is optimized through particle swarm optimization algorithm to improve voltage stability and system reliability. The simulation results show that the stability of power supply in the system has been significantly improved after the installation of mobile energy storage, which provides important reference for the optimization of future emergency power supply systems.