| 摘要 |
PROBLEM TO BE SOLVED: To increase mechanical strength, to prevent ignition or explosion caused by an internal short circuit and to increase safety by forming a separator with at least one layer containing a solid polymer electrolyte and at least one layer containing a thermoplastic polymer compound with the Vicat softening temperature of a specific value or below. SOLUTION: Porous polymer powder is dissolved in an organic solvent to form a polymer solution, lithium salt is dissolved in this polymer solution to form a uniform solution, it is applied on a flat plate to evaporate the organic solvent, and a residual material is peeled off from the flat plate to manufacture a solid polymer electrolyte film. A thermoplastic polymer compound with the Vicat softening temperature 100 deg.C or below, e.g. polyethylene or polypropylene, is formed into a fiber shape to manufacture a film made of a nonwoven fabric from fibers, or it is formed into a film shape to manufacture a porous film bored with many fine holes. One solid polymer electrolyte film and one porous film are laminated to form a separator. This separator is impregnated with an organic electrolyte to be used for a battery. |
