| abstract |
An electrochemical cell liaving a solid polymer separator/electrolyte (15) whose ion conductivity is markedly increased by in situ generation of a fluid acidic anhydride. The electrochemical cell comprises a solid polymer electrolyte (15), an anode (17) of an alkali or alkaline earth metal such as lithium and a cathode (13) containing the lithium or other alkali or alkaline earth metal salt of the acid anhydride to be electrochemically generated in addition to the main active material. The salt has the formula MAxOy where M is an alkali or alkaline earth metal such as lithium and A is a non -metallic element such as sulphur, nitrogen, carbon or pbosphoros 0.3 < = x < = 2.0 and 1.3 < = y < = 4. The electrochemical cell has a much improved rate capability and low temperature performance, but no liquid constituents are required for assembly of the cell. |