A bipolar membrane in which a cation-exchange membrane and an anion-exchange membrane are joined to each other, wherein a leakage ratio of gluconic acid at 60 C. is not more than 1.0%, and the cation-exchange membrane is supported by a polyolefin reinforcing member and, further, contains a polyvinyl chloride.

Disclosed herein are materials for use in battery separators. They include copolymers of a divinylbenzene and one or both of the monomers below (non-linked and linked). R is an n-alkylene group, and n is a positive integer. The copolymer made be made from tertiary amine monomers that are converted to quaternary amines. One battery includes a zinc anode, a silver cathode, and a tri-layer separator. The inner layer uses the linked monomer, and the outer layers use the non-linked monomer.

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Disclosed herein are materials for use in battery separators. They include copolymers of a divinylbenzene and one or both of the monomers below (non-linked and linked). R is an n-alkylene group, and n is a positive integer. The copolymer made be made from tertiary amine monomers that are converted to quaternary amines. One battery includes a zinc anode, a silver cathode, and a tri-layer separator. The inner layer uses the linked monomer, and the outer layers use the non-linked monomer. ##STR00001##