Patent ID: 8691426

Claim:
A secondary battery comprising: an electrode assembly; a can containing the electrode assembly and comprising: a plate; and a wall extending from the plate in a first direction to define a cavity and an opening opposite the plate; and a cap assembly sealing the electrode assembly in the can, wherein the wall comprises first and second walls that face each other, and third and fourth walls that face each other, each of the third and fourth walls connecting the first and second walls to each other, an area of the first and second walls being larger than an area of the third and fourth walls, and wherein the third wall comprises a first corner portion of the wall proximate the first wall and a third corner portion of the wall proximate the second wall, and the fourth wall comprises a second corner portion of the wall proximate the second wall and a fourth corner portion of the wall proximate the first wall, a portion of the wall comprising the first and second walls and the first and second corner portions being thicker than another portion of the wall comprising the third and fourth corner portions.