| 摘要 |
PROBLEM TO BE SOLVED: To provide a battery separator made of a porous film in which electrolyte quickly permeates all over, and allow no occurrence of a phenomenon deteriorating battery performance in a battery can. SOLUTION: A polyolefine porous film is soaked on a solution prepared by dissolving ethylene carbonate in dimethyl carbonate so as to be impregnated with the solution inside microprobes under a reduced pressure. Thereafter, the porous film is extracted from the solution, and is left under the reduced pressure so as to volatilize the dimethyl carbonate. Thereby, ethylene carbonate deposits in the microprobes. In a battery separator obtained this way the ethylene carbonate in the microprobes displays excellent affinity with an organic electrolyte, and the electrolyte permeates into the entire separator quickly in a filling process of the organic electrolyte in the a battery can so that a time required for such filling process can be shortened. |
