Electrolyte for electrochemical device, method for preparing the electrolyte and electrochemical device including the electrolyte

A solid electrolyte for a flexible electrochemical device, consisting of a composite consisting of:

• a plastic crystal matrix electrolyte doped with an ionic salt;
• a semi-interpenetrating polymer network comprising a non-crosslinked polymer and a crosslinked polymer;
• optionally residual solvent;
• and
• optionally a photoinitiator;
• wherein the semi-interpenetrating polymer network is formed in the plastic crystal matrix electrolyte,
• wherein the non-crosslinked polymer is selected from:
• polyethylene oxide, polyvinylidene fluoride-co-hexafluoropropylene and polyacrylonitrile as linear polymers;
• poly(methoxy polyethylene glycol methacrylate) and poly(2-methoxy ethyl glycidyl ether) as branched polymers;
• and mixtures thereof,
• wherein the crosslinked polymer structure is obtained by polymerization of a monomer having two or more functional groups selected from trimethylolpropane ethoxylate triacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, ethoxylated bisphenol A dimethacrylate, and mixtures thereof, and
• wherein said solid electrolyte is suitable for use in a flexible electrochemical device.