PEO‐based polymer electrolytes

Like a liquid solvent, poly(ethylene oxide) dissolves a wide variety of inorganic salts. Ionic conductivity occurs in the amorphous region of the polymer and typically both anions and cations are mobile to some extent. This paper discusses the preparation, thermal behaviour and ionic transport of thin cast films of PEO‐based electrolytes containing monovalent and divalent cations. The techniques that shed light on the structure‐conductivity relationship are emphasized. The temperature and composition dependence of conductivity is also considered. Finally, attention has been paid to the possible uses of these polymeric electrolytes in solid‐state electrochemical devices such as primary and secondary batteries, electrochromic displays and sensors.