Lithium-ion secondary battery and manufacturing method for same

摘要

An object of this present invention is to provide: a lithium-ion secondary battery 1 constructed to easily interpose an electrical insulating protection film 41 between a battery container 2 and an electricity-generating element 3, to facilitate automatic mounting of the insulating protection film 41, and thus to be highly producible; and a method of manufacturing the battery. The lithium-ion secondary battery 1 of the invention is characterized in that the battery is electrically insulated between the battery container 2 and the electricity-generating element 3, and in that the insulating protection film 41 of a sheet-like form is wrapped around the electricity-generating element 3.

主权项

1. A lithium-ion secondary battery, comprising:
an electricity-generating element including a wound electrode structure that is formed by winding electrodes into a flat form, wherein the electrodes are connected to a pair of electrode terminals; a battery container that includes: a battery casing having an opening, a battery cover configured to cover the opening in the battery casing, and one pair of electrode terminals provided on the battery cover via an electrical insulating member; and an electrical insulating protection film of a sheet-like form that is wrapped around the wound electrode structure and the pair of electrodes in a direction that is orthogonal to an axial direction of the winding of the wound electrode structure, wherein the electrical insulating protection film includes: a protruding end portion on a lateral end of the insulating protection film that extends beyond the wound electrode structure towards a bottom of the battery casing and away from the battery cover, wherein the protruding end portion have opposed portions that are joined together into mutual surface contact, a fold over integral to the protruding end portion that is formed by folding lowermost edges of the opposed portions, and a sealed portion formed by sealing off the lowermost edges of the opposed portions.