Photoinduced free radical polymerization of thermoset lithium battery electrolytes

Series of solid poly(ethylene oxide)-methacrylate electrolytes have successfully been manufactured with an aim to serve in a multifunctional battery both as mechanical load carrier as well as lithium ion conductor. The electrolytes produced, in a solvent free process with no post cure swelling, hold a broad range of both mechanical as well as ion conducting properties. The monomer and Li-salt mixtures have been irradiated with UV light, initiating free radical polymerization to obtain solid smooth, homogenous specimens to be utilized as ion conducting electrolytes. The storage modulus at 20 °C is ranging from 1 MPa to almost 2 GPa. The conducting ability of the electrolyte ranges from 5.8 × 10−10 up to 1.5 × 10−6 S/cm. These large variations in both mechanical properties as well as ionic conductivity are discussed, but also the versatility within the production technique is emphasized.