Abstract: It is very important for the safe operation of the energy storage system to study the fire warning technology of Li-ion battery energy storage power station. The recognition of thermal runaway and thermal diffusion characteristics of lithium-ion batteries is discussed. The combustible gases will be generated slowly at the beginning the thermal runaway of lithium-ion batteries. if the gas of thermal runaway of batteries can be extracted and analyzed in the early state, the thermal runaway early warning system of the battery can be established on this basis. In this paper, heating and overcharging methods were used to trigger the battery thermal runaway and gas emission, and the gas composition is analyzed, it is confirmed that carbon monoxide can be detected to achieve early warning of Li-ion battery thermal runaway. It introduces the application status of fire warning system in energy storage power station and points out its shortcomings. The multilevel early warning and protect mechanism and security linkage strategy were studied. At last, the design framework of fire warning system for lithium ion battery energy storage power station is exported. The system is briefly explained from the aspects of system components, linkage communication and personnel safety. The system ensures fast and effective detection of the thermal runaway state of batteries while fast linkage of fire protection facilities, greatly improving the reliability of the energy storage system.

Key words: Li-ion battery, thermal runaway, energy storage, fire safety, early warning