In solid polymer electrolyte having high-durability, comprising a polymer electrolyte material having a hydrocarbon part, a chelate group and an electrolyte group are introduced into the polymer electrolyte material. The chelate group contains a phosphonic acid group, nitrogen, both of nitrogen and a...http://www.google.co.uk/patents/US6607856?utm_source=gb-gplus-sharePatent US6607856 - Solid polymer electrolyte having high-durability
