二次電池、バッテリーパック及び電子装置

Abstract

The present invention provides a secondary battery, a battery pack, and an electronic device in which a positive electrode tab is less likely to be displaced after being collapsed during a press bending process. [Solution] The secondary battery includes a casing, an electrode assembly, and a current collecting member. The electrode assembly is housed in the casing and includes a wound structure formed by stacking and winding a positive electrode sheet, a negative electrode sheet, and a separator. The positive electrode sheet includes a positive electrode coated area, a positive electrode uncoated area, and an insulating layer covering at least the boundary between the positive electrode coated area and the positive electrode uncoated area. The positive electrode uncoated area extends outside the separator and is folded toward the winding axis to form a positive electrode uncoated area stacking area. The current collecting member is welded to the positive electrode uncoated area stacking area. The insulating layer includes a first insulating layer facing the winding axis and a second insulating layer away from the winding axis. Both the first insulating layer and the second insulating layer extend along the winding axis toward the positive electrode uncoated area stacking area. The height h1 of the first insulating layer is greater than the height h2 of the second insulating layer.

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