| 摘要 |
PURPOSE:To improve wettability of a separator with an electrolyte when a high boiling point solvent is used to decrease internal resistance by treating a separator made of a microporous polypropylene film with a specific surface active agent. CONSTITUTION:A separator made of a microporous polypropylene film is treated with a surface active agent separated from a group of oleic amid-ethylene oxide addition product, oleic amide, oleic diethanolamide, and oleoyl diethanolamine. By this treatment, affinity to an organic solvent is given to the separator, and wettability of the separator to the solvent having high surface tension is improved. Althrough these surface active agents are soluble in the organic solvent, they have not so much harmful effect on battery performance. Thereby, wettability of the separator to the gelled organic electrolyte is improved, yield in production is increased, internal resistance is decreased, and the scattering of the internal resistance is reduced. |
