Patent attributes
The invention provides a nonaqueous electrolyte secondary battery excellent in output characteristic such as large current discharge or pulse discharge in ordinary use, high in safety by preventing destruction due to suppression of current in an abnormality such as external short-circuiting, and further large in capacity. The nonaqueous electrolyte secondary battery comprises an external can opened at one end thereof, an electrode assembly contained in the external can, and comprising a negative electrode, a separator and a positive electrode, a nonaqueous electrolyte contained in the external can, and a sealing lid group tightly sealed at the opening of the external can by way of an insulating member, wherein the sealing lid group includes an intact plate-like PTC element having a fragile portion to be easily broken due to elevation of internal pressure by gas generation.
