IONIC LIQUIDS, ELECTROLYTE SALTS FOR ELECTRICAL STORAGE DEVICES, LIQUID ELECTROLYTES FOR ELECTRICAL STORAGE DEVICES, ELECTRICAL DOUBLE-LAYER CAPACITORS, AND SECONDARY BATTERIES

摘要

Electrical storage devices having excellent low-temperature properties can be obtained by using a quaternary salt (or ionic liquid) of general formula (1) below as an electrolyte salt for electrical storage devices or a liquid electrolyte for electrical storage devices. In formula (1), R¹ to R⁴ are each independently an alkyl group of 1 to 5 carbons or an alkoxyalkyl group of the formula R′—O—(CH₂)_n—, with the proviso that at least one group from among R¹ to R⁴ is the above alkoxyalkyl group. X is a nitrogen or phosphorus atom, and Y is a monovalent anion.