CA2268888A1 — Separator for battery and alkali secondary battery using the same

USPTO Abstract

A separator for batteries comprising exchangeable fine powder (4) prevented from coming off by fixing the powder (4) by using a binder resin (3) which is placed in fine pores (2) or narrow grooves formed in the surface of organic fibers (1) constituting a porous sheet, having an excellent electrolyte holding property, and exhibiting an ion exchanging ability for a long period. The pores (2) or grooves exist in the surface of olefin fibers (1). The pores (2) or grooves are formed by etching the fibers (1) with an organic solvent. In the pores (2) or grooves, the binder resin (3) is fixed, partially entering the pores (2) or grooves and projecting outward from the pores (2) or grooves. The ion-exchangeable fine powder (4) is fixed to the ends of the projecting resin (3). It is preferable to use a styrene-ethylene-butylene-styrene (SEBS) thermoplastic copolymer as the resin (3).