Battery cell with improved pressure relief vent

A electrochemical cell, wherein pressure relief hole is formed on the metal plate; the metal plate is arranged in the shell closed end opening end at least one. The pressure relief hole with the loop, comprising a groove of the thins; the groove at least one first base plate is provided with thinned the part separately. In a hole to release the voltage of battery; the link board in the area is at least one is not thinned component, and further connected with the remainders of plate. The form of a pressure relief the air cylinder is can serve as a shell of electrochemical cells on the base.