TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Components: The uncoated region comprises: a slant region extending toward the end portion of the coated region; and a junction region connected to the slant region and coupled to the lead tab, where the through hole is at least formed at the slant region. The through hole is: formed as a slot extending from the slant region to the junction region; and penetrated and formed in a direction intersecting the slant region in the slant region. The electrode assembly further comprises a first outer surface and a second outer surface opposite the first outer surface, where: in the uncoated region, the first outer surface is a planar surface extending between the junction region and the slant region; the second outer surface comprises a curved surface between the junction region and the slant region; and the first outer surface comprises a first curved surface between the junction region and the slant region, and the second outer surface comprises a second curved surface between the junction region and the slant region that is symmetrical to the first curved surface. The electrode assembly includes many uncoated regions, where: the through hole is formed through the uncoated regions in the slant region; the through hole has a largest area at the second outer surface and a smallest area in the first outer surface, or a largest area at the first and second outer surfaces and a smallest area at a location that is central between the first and second outer surfaces; the slant region includes passages between the uncoated regions; and the passages form a largest opening area at side proximate the second outer surface and a smallest opening area at a side proximate the first outer surface, and are connected to the through hole, or the passages form a same largest opening area at sides proximate the first and second outer surfaces and a smallest opening area at a location that is central between the first and second outer surfaces.