Patent ID: 8895167
Filing Date: 2014-11-25
Classification: H01M,Y02E,Y02P

Abstract:
1. A secondary battery, comprising: an electrode assembly having a positive electrode plate and a negative electrode plate, and further including a separator interposed between the positive and negative electrode plates; a case having a space for containing the electrode assembly and having a plurality of sides including a first side, the first side having at least one element to compensate for and prevent volumetric expansion of the case arranged at a center portion of the first side and a peripheral portion of the first side surrounding said at least one element, the at least one element being a protruding ridge that protrudes further towards an exterior of the case than the peripheral portion of the first side; and a cap assembly attached to the case for sealing the case, the cap assembly including a terminal portion electrically connected to the electrode assembly; wherein a thickness t wherein said at least one element is arranged only at the central portion of the first side of the case, the at least one element including a first protruding portion and second protruding portions extending from each opposing end of the first protruding portion and forming oblique angles with a longitudinal direction of the first protruding portion.