Patent ID: 9741987
Date: 2017-08-22
CPC Classifications: H01G,H01M,Y02E,Y02P,Y02T

Claim:
1. An electricity storage device comprising: a first electrode sheet including two surfaces and an active material layer, which is located on at least one of the two surfaces; a separator, which covers the two surfaces of the first electrode sheet; and a second electrode sheet, which includes two surfaces and an active material layer, which is located on at least one of the two surfaces, wherein the second electrode sheet differs from the first electrode sheet in polarity, wherein the first electrode sheet, the separator, and the second electrode sheet are layered to form an electrode assembly, the first electrode sheet includes a first edge and a tab, wherein the tab projects in an extension direction away from the first edge, the separator includes: the primary weld region has a region width in the protrusion direction of the pair of the primary protrusions that is greater than a region width of each of the secondary weld regions in protrusion directions of the corresponding pair of the secondary protrusions, and the second electrode sheet includes a second edge that projects beyond the first edge of the first electrode sheet in the extension direction of the tab of the first electrode sheet, and the region width of the primary weld region is greater than or equal to a sum of: