| 摘要 |
PROBLEM TO BE SOLVED: To make it difficult to generate the internal short circuit, and to prevent rupture and ignition of a battery when a nail, etc., is pierced in a battery can of the battery in the charged condition by providing a rubber material which is high in elasticity and shows the electric insulation at least on a part of a separate substance and/or an electrode body. SOLUTION: A negative electrode, a positive electrode and a spiral electrode body 14 around which the separate substance is wound, are stored in a battery can. A rubber material which is high in elasticity, i.e., >=3kg/cm<2> in tensile strength and >=10kg/cm<2> in breaking strength, and shown the electric insulation, is provided on the outer circumference of the separate substance and/or the spiral electrode body 14. Even when a projection is pierced from the outside of the battery can, contact of the positive electrode with the negative electrode is prevented by the elasticity of the rubber when the rubber material is provided on the separate substance. When the sheet-like latex rubber 15 of the rubber material is provided on the outer circumference of the spiral electrode body 14, the rubber is entangled around the projection to prevent the contact with the positive electrode with the negative electrode, and the electrode reaction by the internal short circuit can be prevented. |
