Inventors

Michel Armand (CIC energiGUNE) and Devaraj Shanmukaraj (CIC energiGUNE)

Abstract

Researchers at CIC energiGUNE have developed a novel family of PVA-based dry polymer electrolytes with high ionic conductivity and good electrochemical stability.

The choice of polymer matrix is a critical criterion for obtaining a highly conductive and mechanically/electrochemically stable polymer electrolyte at close to ambient operating temperatures. In order to obtain the aforementioned properties, the polymer matrix should possess better Li⁺ solvation properties and facilitate faster Li salt dissociation. In this sense, Poly Vinyl Alcohol (PVA) was chosen due to its excellent film forming property, biodegradability, non-toxicity and non-carcinogenetic and excellent chemical resistance.

The polymer electrolytes of the invention have a PVA polymer backbone with side chain esters. The esters can either be a single ester or a double ester group or even a salt anion attached to the ester group. This modification facilitates the high flexibility of the polymer chain thereby leading to a decreased T_g value and high ionic conductivity at close to ambient temperature for successful high performance solid-state batteries compatible with high voltage cathodes.

Added value

• High ionic conductivity at close to ambient temperatures


• High electrochemical stability


• Simple synthesis technique, easily upscalable

Application of the technology

• Li metal polymer batteries


• Post lithium solid-state batteries