Automatic fire extinguishing device for battery box (hereinafter referred to as fire extinguishing device). This product adopts a number of technology integration research projects of the Ministry of public security technology application innovation plan: Research on early warning and automatic fire extinguishing system of bus fire《 The research results of "Research on fire characteristics and fire extinguishing technology of lithium-ion battery for electric vehicles" are used for the fire warning and extinguishing technology of lithium-ion power battery and capacitor in the energy storage device compartment of new energy vehicles. It can effectively detect and alarm the early fire of lithium-ion battery or capacitor in the energy storage device compartment, and realize automatic fire extinguishing and continuous suppression, and put an end to electricity The pool and capacitor are ignited again. The equipment system has a number of value-added service functions to realize intelligent management system, visual work effectiveness, automatic inspection and diagnosis, fault alarm. Built in Flash+RAM memory, equipment and source data, abnormal data storage, Internet of things, Internet plus upgrade interface.