Toray develops ion-conducting polymer film for batteries

Toray Industries has announced the development of an ion-conducting polymer membrane with 10 times the ionic conductivity of its predecessor.

This new product can accelerate the deployment of solid-state batteries, air batteries and other lithium metal batteries, greatly extending the range of electric vehicles, industrial drones, urban air transportation systems and other transportation modes.

Toray has developed a polymer membrane that provides ion conductivity through hopping conduction. This mechanism enables lithium ions to traverse between interacting sites within polymer membranes, effectively jumping across sites. The membranes remain non-porous. The breakthrough leverages the company's expertise in molecular design technology, specifically aramid polymers that have been refined over many years.

Toray estimates that enhancing the hopping site structure and designing new polymers with more hopping sites can provide hopping conductive polymer films with the highest ionic conductivity in the range of 10-4 S/cm.

Toray confirmed that the polymer film can effectively act as a protective film on the surface of lithium metal, overcoming the previously mentioned problems and should extend the life of batteries using lithium metal anodes.

Joint research with Professor Nobuyuki Imanishi of the Graduate School of Engineering at Mie University verified the achievement of 100 charge-discharge cycles for the first time in a dual component lithium-air battery employing this polymer membrane as a separator.

Toray will accelerate research to quickly establish technologies for solid-state batteries, air batteries and other advanced batteries.

Part of the development of the new membrane was carried out through a project funded by the New Energy and Industrial Technology Development Organization (NEDO). Toray plans to showcase its technology at the 91st Annual Meeting of the Electrochemical Society of Japan, which will be held from March 14 to 16 this year.

Toray will continue to leverage its core technologies of synthetic organic and polymer chemistry, biotechnology, and nanotechnology to innovate materials to fulfill its commitment to provide new value and contribute to social progress.