Laminated separator for alkaline batteries is prepd. - from water-wetted porous nonwoven sheet of hydrophilic fibres and non-wettable fibres, and from film insol. in electrolyte but sol in water

摘要

The separator (I) comprises (A) nonwoven sheet made from hydrophilic fibres and non-wettable fibres, followed by further treatment, which is adapted to absorb the electrolyte (II), resistant to (II), and sufficiently porous to allow passage of ions of (II), (B) film adhering to a face of (A), which is adapted to hold back the metal ions, is insol. in (II), and of material sol. in water at above 10 deg.C. Prepn. of (I) by (1) wetting one of the 2 faces of (A) with water, (2) applying (B) to this face, (3) immediately heating (A) on opposite face to remove excess water and effect adhesion of (B) on (A). Rechargeable or non-rechargeable alkaline batteries contg. (I), or (I) made by above process. ADVANTAGE - (A) has good absorption and retention properties for (II), (B) prevents migration of metallic ions and formation of Zn dendrites which can form bridge between electrodes, causing short circuit; (I) is made in one stage without use of adhesive which might cause loss of electrical performance.