| abstract |
Provided is a lithium ion secondary battery having excellent durability. A lithium ion secondary battery is provided with: a positive electrode provided with an aluminum collector; a negative electrode; and an electrolyte solution containing an electrolyte containing a lithium salt and a chain carbonate represented by the following general formula (2), wherein the chain carbonate is contained in a molar ratio of 3 to 6 relative to the lithium salt, and the electrolyte contains a first lithium salt represented by the following general formula (1) and an alkali metal salt selected from the following general formulae (a) to (D): (R) 1 X 1 )(R 2 SO 2 ) NLi of the formula (1), R 20 OCOOR 21 General formula (2), MPF 6‑y (X) y (wherein y is an integer of 0 to 5) formula (A), MBF 4 ‑y(X) y (wherein y is an integer of 0 to 3) formula (B), MAsF 6‑y (X) y (wherein y is an integer of 0 to 5) formula (C), M 2 SiF 6‑y (X) y (wherein y is an integer of 0 to 5) a general formula (D). |