| 摘要 |
PURPOSE:To prevent the short circuit current of a battery and the deterioration of the heavy-load discharge characteristic due to the effect of a remaining sulfide by heat-treating synthetic fibers of polyvinyl alcohol at 230-250 deg.C then forming a viscose film on the surface. CONSTITUTION:Synthetic fibers of polyvinyl alcohol are heat-treated at the temperature of 230-250 deg.C, thereby the heat resistance of the synthetic fibers of polyvinyl alcohol can be improved, and the temperature of the washing water to remove a remaining sulfide after a viscose film is formed on the surface of an electrolyte impregnating material made of synthetic fibers of polyvinyl alcohol can he made higher than that in the past. As a result, the remaining sulfide in the forming process of the viscose film 4c can be reliably removed without softening and shrinking the synthetic fibers of polyvinyl alcohol. Accordingly, the short circuit current and the deterioration of the heavy-load discharge characteristic caused by the remaining sulfide can be prevented. |
