| abstract |
Disclosed is an aqueous electrolytic solution which is difficult to decompose and decompose and can improve battery characteristics when applied to a lithium ion secondary battery. Water, lithium ion, and ammonium cation, piperidinium cation, phosphonium cation, and phosphonium cation in the cation that can become an ionic liquid when TFSI anion and salt are constituted in the air atmosphere, At least one kind of cation selected from the group consisting of an imidazolium-based cation, and TFSI anion is used as an aqueous electrolyte solution for a lithium ion secondary battery. |