Patent attributes
A safety mechanism for a laminate battery. An exterior case (5) consists of two molded sheets (5a) made of laminate sheets, superposed upon one another, and bonded together around the outer edges. The exterior case has a protrusion (10) that communicates with the interior of the exterior case and protrudes outwardly from one side. A safety vent (13) is made up of an exhaust hole (11) formed in at lease one of the two molded sheets (5a) in the protrusion (10), and a valve element (12) making elastic pressure contact with the edge of the exhaust hole (11) to seal it. The safety mechanism does not operate within the range of internal pressure variation during normal use, but operates reliably at a time point when a predetermined valve operating pressure is reached to release a necessary amount of gas to the outside, this valve operating pressure being within the safe range relative to the pressure resistance of the exterior case (5) made of laminate sheets. Also, the safety vent configuration enables a reduction in production cost.