NONAQUEOUS ELECTROLYTE, ELECTRICAL DOUBLE-LAYER CAPACITORS, AND NONAQUEOUS ELECTROLYTE SECONDARY CELLS

摘要

A nonaqueous electrolyte comprising both an ionic fluid which is represented by the general formula (1) and takes a liquid form at 50~C or below and an ionically conductive polymer. This electrolyte brings about secondary cells and electrical double layer capacitors which are excellent in charge/dischar ge efficiency, stability, low-temperature characteristics, and so on: (1) where in R1 to R4 are each independently alkyl having 1 to 5 carbon atoms or an alkoxyalkyl group represented by the general formula: R~-O- (CH2)n- (wherein R~ is methyl or ethyl and n is an integer of 1 to 4), or any two of R1 to R4 may form a ring, with the proviso that at least one of R1 to R4 is an alkoxyalkyl group described above; X is nitrogen or phosphorus; and Y is a monovalent anion.