SECONDARY BATTERY HAVING ANTI-SCATTERING MECHANISM

摘要

Peripheral-side thin-walled portions (11) are formed by cutting out the inner surface of a top plate portion (18a) in parallel with a pair of longitudinal ends (18e) in the vicinity of the longitudinal ends (18e) of a lid (18) that constitutes a case body for housing an electrode group and electrolyte. A central-side thin-walled portion (15) is formed by cutting out the outer surface of the central portion of the top plate portion (18a) in parallel with the longitudinal ends (18e). As a result, when the case body (1) bursts due to increased inner pressure, the case body (1) can be burst early while the strength of the case body (1) relative to the outer pressure can be maintained.