| 摘要 |
Provided is a nonaqueous electrolyte solution with which it is possible to obtain a nonaqueous electrolyte secondary battery in which the initial charging capacity, input/output characteristics, and impedance characteristics are improved. Specifically, disclosed is a nonaqueous electrolyte solution which contains a nonaqueous solvent and/or LiPF6 and/or a fluorosulfonic acid salt represented by the formula (1) M(FSO3)x, wherein the ratio of the molar content of FSO3 in relation to the molar content of PF6 in the nonaqueous electrolyte solution is between 0.001 and 1.2. Also disclosed is a nonaqueous electrolyte secondary battery containing said nonaqueous electrolyte solution. [In the formula (1), M represents a metallic atom, N(R)4, or P(R)4 (wherein R represents a C1-12 organic group or a hydrogen atom (however, all four Rs may not represent a hydrogen atom), may mutually be the same or different, and all four Rs or a portion of the four Rs may form a ring with the nitrogen atom or the phosphorous atom to which the four Rs may be bound). When M represents a metallic atom, x represents the valence of the metallic atom (M), and represents an integer of 1 or more. When M represents N(R)4 or P(R)4, x represents the number 1.] |
