| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polymeric solid electrolyte having ionic conductivity and uniformity, and good adherence to a base material by using as the constituents a linear copolymer of vinylidene fluoride and chlorotrifluoroethylene, an electrolyte salt, a solvent, and a polymeric component with low degree of polymerization. SOLUTION: The copolymer of vinylidene fluoride (VDF) and chlorotrifluoroethylene (CTFE) realizes the reduction in the crystallizability of VDF by CTFE with almost no reduction in melting temperature and crystallization temperature to thereby serve to form a flexible solid electrolyte and improve the low-temperature characteristics. The VDF-CTFE copolymer preferably contains 5-50 mol.% CTFE and has an Mw of at least about 30,000. The copolymer is obtained by polymerizing VDF and CTFE by using a peroxide catalyst. An oligomeric component (e.g. a PVDF having a weight-average molecular weight of 300 to 5,000) may be added to the gel electrolyte. The use of the polymeric solid electrolyte can give an electrochemical device excellent in durability, shelf life and productivity. |
