An electrochemical device , the electrochemical device comprises: a housing , wherein the housing defines an accommodation cavity , the housing comprises a first sidewall , the first sidewall comprises a first wall face oriented toward the accommodation cavity and a second wall face oriented away from the accommodation cavity , and the first sidewall comprises a mounting hole , the mounting hole running through the first wall face and the second wall face ; an insulation assembly , connected to the first wall face or the second wall face ; the insulation assembly comprises a first insulator , the first insulator comprises a penetrative first through-hole , and the first through-hole communicates with the mounting hole ; an electrode post , comprising a first part and a second part , the first part is connected to an end face of the insulation assembly , the end face of the insulation assembly is oriented away from the first sidewall , the first part covers the first through-hole , the second part is disposed in the mounting hole and the first through-hole , one end of the second part is connected to an end face of the first part , and the end face of the first part is oriented toward the first sidewall ; and the first insulator is configured to be melted when a temperature in the accommodation cavity rises to a first threshold, and generate, under an action of a gas pressure in the accommodation cavity , a pressure relief channel that communicates the accommodation cavity to an outside of the housing , characterized in that the insulation assembly further comprises a second insulator ; in a thickness direction of the first sidewall , the first insulator and the second insulator are stacked together; the second insulator comprises a penetrative second through-hole , the penetrative second through-hole communicates with the first through-hole and the mounting hole , and a melting point of the second insulator is higher than the first threshold. a housing , wherein the housing defines an accommodation cavity , the housing comprises a first sidewall , the first sidewall comprises a first wall face oriented toward the accommodation cavity and a second wall face oriented away from the accommodation cavity , and the first sidewall comprises a mounting hole , the mounting hole running through the first wall face and the second wall face ; an insulation assembly , connected to the first wall face or the second wall face ; the insulation assembly comprises a first insulator , the first insulator comprises a penetrative first through-hole , and the first through-hole communicates with the mounting hole ; an electrode post , comprising a first part and a second part , the first part is connected to an end face of the insulation assembly , the end face of the insulation assembly is oriented away from the first sidewall , the first part covers the first through-hole , the second part is disposed in the mounting hole and the first through-hole , one end of the second part is connected to an end face of the first part , and the end face of the first part is oriented toward the first sidewall ; and the first insulator is configured to be melted when a temperature in the accommodation cavity rises to a first threshold, and generate, under an action of a gas pressure in the accommodation cavity , a pressure relief channel that communicates the accommodation cavity to an outside of the housing , characterized in that the insulation assembly further comprises a second insulator ; in a thickness direction of the first sidewall , the first insulator and the second insulator are stacked together; the second insulator comprises a penetrative second through-hole , the penetrative second through-hole communicates with the first through-hole and the mounting hole , and a melting point of the second insulator is higher than the first threshold. <EOS>