Block copolymer battery separator

Wong, David; Balsara, Nitash Pervez

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DOE OSTI · 1248819

Block copolymer battery separator

Wong, David·Balsara, Nitash Pervez

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Abstract

The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.

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25 ENERGY STORAGE 36 MATERIALS SCIENCE

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Wong, David, Balsara, Nitash Pervez. 2016-04-26. Block copolymer battery separator. https://www.osti.gov/biblio/1248819

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