| 摘要 |
PROBLEM TO BE SOLVED: To provide a battery wherein gas is smoothly discharged in the event of an increase in internal pressure caused by an accidental misuse, and leakage of an electrolytic solution is prevented with higher reliability. SOLUTION: In the battery 1 wherein a positive electrode 3, a negative electrode 5 and electrolyte are contained in a tubular battery can 2 having a bottom, an opening of the battery can 2 is sealed by a battery cover 12, and the battery cover 12 has a convex portion with a gas discharge hole 11 perforated at an outer circumferential face, a covering material 14 made from a resin material and having a through-hole is fitted to the outer circumferential face of the convex portion of the battery cover 12. Supposing that an inner diameter of the covering material 14 before being fitted is W, and that an outer diameter of the convex portion is D, W and D meets a relation given by an equation of 0.0005<=(D-W)/D<=0.0365. |
