Abstract In recent years, due to the influence of policies such as environmental protection and reduction of harmful gas emissions, clean energy such as lithium batteries, hydrogen-oxygen fuel cells, and waste heat power generation technologies are being applied on ships. As the application level of new energy continues to expand, its safety issues have attracted more and more attention from society. The system collects the air pressure, temperature, humidity, flame heat radiation, and smoke information inside the ship’s power battery box, and uses the STM32 processor to determine whether the ship’s power battery has a fire hazard. This system can effectively avoid the thermal runaway of the power battery, detect the thermal runaway at an early stage and actively respond to reduce losses, and protect the life and property safety of passengers on board.