| 摘要 |
PURPOSE:To prevent the generation of fuming and ignition at overcharge time or at internal short-circuit time and the like, even in the case of forming into a large capacity, by forming a separator of resin containing a solid granular flame retarder. CONSTITUTION:A layered product, laminating positive/negative electrode plates 2, 3 through a separator 8a, is stored in a flat angular battery vessel 10. The separator 8a is formed of resin containing a solid granular flame retarder, and as this resin, polyethylene, polypropylene, etc., are used. When the separator 8a is formed, relating to the resin of polyethylene, polypropylene, etc., 3 to 30wt.% the solid granular flame retarder is mixed, kneaded thereafter rolled, and also drawn, to form a sub mu sized fine porous film of 50mum thickness. Here is set a grain size to 0.05 to 0.3mum in the solid granular flame retarder. Thus in the case of forming into a large capacity, generation of fuming and ignition of the separator 8a, at overcharge time, internal short-circuit time, etc., is eliminated, and safety can be improved. |
