| 摘要 |
A polymer electrolyte for use in electrochemical cells comprises a polymer combined with a solution of a salt in a plasticising solvent, wherein the polymer is a copolymer of vinylidene fluoride and between 1 and 8% by weight of hexafluoropropylene. The copolymer has a sufficiently high molecular weight to form a mechanically strong polymer film, and so has a low value of melt flow index, which at 230{C and 10 kg is less than 5.0 g/10 min, and preferably less than 1.0 g/10 min. A film of the polymer electrolyte can be cast from a volatile solvent, while the plasticising solvent can be selected to achieve the desired electrical properties. Electrical cells using this electrolyte have a high capacity, which does not decrease rapidly with cycling. |
