Toray Industries, a Japanese performance chemical manufacturer, has developed an ion-conductive polymer membrane that it says delivers 10 times the ion conductivity of its predecessors.

The new polymer membranes offer ion conductivity through hopping conduction. This mechanism enables lithium ions to traverse between interacting sites within polymer membranes, jumping across sites. The membranes remain non-porous. Toray estimates that enhancing the hopping site structure and designing a new polymer with more hopping sites has delivered an ionic conductivity in the 10^-⁴ S/cm range for a hopping-conductive polymer film. It confirmed that the polymer film functions effectively as a protective film on lithium metal surfaces to extend the service lives of batteries using lithium metal lithium 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.

“This new offering could accelerate the deployment of solid-state batteries, air batteries, and other lithium metal batteries, to expand the cruising ranges of EVs, industrial drones, urban air mobility systems and other transportation modes,” the company said.

Source: Toray