Abstract: A battery separator and a method for manufacturing the same and a battery using the same. The battery separator is excellent in alkaline retaining property, initial alkaline absorption and durable alkaline absorption while maintaining tensile strength and air permeability, by forming functional groups or bonds of —CHO or —C+H—O−, —CO—, and —COO— or —COO−on the surface of the non-woven fabric. The battery shows great wettability with an alkaline electrolyte when incorporated into an battery, and thus, improves the battery life.

Abstract: Conjugate fibers using, as a surface component, ethylene copolymer containing a unit represented by a formula --CH.sub.2 --CH(COOH)--, and using, as a core component, polypropylene or like polyolefin fibers, are used to obtain thermally bonded non-woven fabric sheet to the treated with concentrated sulfuric acid or the like. By so doing, it is possible to readily introduce sulfo groups to replace tertiary carbon and thus impart the fibers with hydrophilicity. By using thus sulfonated thermal bonded non-woven fabric sheet as alkaline storage battery separators, it is possible to maintain high discharge capacity retention.