Thymol–Menthol Deep Eutectic Solvent as a Functional Additive for PEO-Based Solid Polymer Electrolytes
This study demonstrates that incorporating a thymol–menthol deep eutectic solvent (specifically at a 1:4 ratio) into a polyethylene oxide (PEO) matrix via solution casting enhances intermolecular hydrogen bonding and significantly improves the ionic conductivity of the resulting solid polymer electrolyte.