Abstract: Provided is a non-aqueous electrolytic solution for a lithium ion secondary cell that uses an additive that can suppress gas generation due to the decomposition of the non-aqueous electrolytic solution and has a low environmental risk.

Abstract: The disclosure provides an electrolyte solution that enables a lithium ion secondary battery to have reduced initial resistance, a small increase in resistance at high-temperature cycles, and reduced gas generation at high temperature. The electrolyte solution for a lithium ion secondary battery contains lithium difluorophosphate, an oxalic acid ion, and a compound (1) represented by the following formula (1): wherein R1 and R2 are each independently a methyl group, an ethyl group, a propyl group, or a butyl group.

Abstract: Provided is an electrolyte solution for lithium secondary batteries that allows lowering the resistance of a lithium secondary battery, and suppressing characteristic degradation of the lithium secondary battery under high temperature. The electrolyte solution for lithium secondary batteries disclosed herein contains 0.05 mass % to 2.0 mass % of a compound represented by Formula (1) below. (In the formula, M+ represents a quaternary ammonium cation or a nitrogen-containing heteroaromatic ring cation, and R1 represents a C1-C5 alkyl group in which an ether oxygen is optionally inserted.

Abstract: Provided is a non-aqueous electrolytic solution for a lithium ion secondary cell that can reduce the initial resistance of the lithium ion secondary cell and can suppress the increase in resistance when the lithium ion secondary cell is allowed to stand at high temperature. The non-aqueous electrolytic solution for a lithium ion secondary cell disclosed herein includes a light metal salt represented by the following formula (I) and a silyl sulfate compound represented by the following formula (II). The content of the light metal salt in the non-aqueous electrolytic solution for a lithium ion secondary cell is 0.1% by mass or more and 1.5% by mass or less. The content of the silyl sulfate compound in the non-aqueous electrolytic solution for a lithium ion secondary cell is 0.1% by mass or more and 5.0% by mass or less (each symbol in the formulas is as defined in the specification).

Abstract: The disclosure provides an electrolyte solution that enables a lithium ion secondary battery to have reduced initial resistance, a small increase in resistance at high-temperature cycles, and reduced gas generation at high temperature. The electrolyte solution for a lithium ion secondary battery contains lithium difluorophosphate, an oxalic acid ion, and a compound (1) represented by the following formula (1): wherein R1 and R2 are each independently a methyl group, an ethyl group, a propyl group, or a butyl group.

Abstract: Provided is an electrolyte solution for lithium secondary batteries that allows lowering the resistance of a lithium secondary battery, and suppressing characteristic degradation of the lithium secondary battery under high temperature. The electrolyte solution for lithium secondary batteries disclosed herein contains 0.05 mass % to 2.0 mass % of a compound represented by Formula (1) below. (In the formula, M+ represents a quaternary ammonium cation or a nitrogen-containing heteroaromatic ring cation, and R1 represents a C1-C5 alkyl group in which an ether oxygen is optionally inserted.

Abstract: Provided is a non-aqueous electrolytic solution for a lithium ion secondary cell that uses an additive that can suppress gas generation due to the decomposition of the non-aqueous electrolytic solution and has a low environmental risk. The non-aqueous electrolytic solution for a lithium ion secondary cell disclosed herein includes an electrolyte salt including a fluorine atom, a non-aqueous solvent capable of dissolving the electrolyte salt, and at least one heteroaromatic dicarboxylic acid anhydride selected from the group consisting of a compound represented by a following formula (I) and a compound represented by a following formula (II) as an additive (wherein, R1 to R7 are as defined in the specification).

Abstract: Provided is a non-aqueous electrolytic solution for a lithium ion secondary cell that can reduce the initial resistance of the lithium ion secondary cell and can suppress the increase in resistance when the lithium ion secondary cell is allowed to stand at high temperature. The non-aqueous electrolytic solution for a lithium ion secondary cell disclosed herein includes a light metal salt represented by the following formula (I) and a silyl sulfate compound represented by the following formula (II). The content of the light metal salt in the non-aqueous electrolytic solution for a lithium ion secondary cell is 0.1% by mass or more and 1.5% by mass or less. The content of the silyl sulfate compound in the non-aqueous electrolytic solution for a lithium ion secondary cell is 0.1% by mass or more and 5.0% by mass or less (each symbol in the formulas is as defined in the specification).