Electrolytic solution, electrochemical device, lithium ion secondary battery, and module
The invention provides an electrolyte solution capable of providing an electrochemical device having low resistance and excellent high-temperature storage characteristics and cycle characteristics. The electrolyte solution contains lithium fluorosulfonate and a solvent containing a compound (1) represented by the following formula (1): CF 2 HCOOCH 3 .
1. An electrolyte solution comprising lithium fluorosulfonate and a solvent comprising a compound (1) represented by the following formula (1):
CF 2 HCOOCH 3 ,
wherein the compound (1) is included in an amount of 30-100% by volume of solvent.
2. The electrolyte solution according to claim 1 ,
wherein the solvent further comprises a fluorinated cyclic carbonate.
3. The electrolyte solution according to claim 1 ,
wherein the solvent further comprises a fluorinated acyclic carbonate.
4. The electrolyte solution according to claim 1 , further comprising a compound (2) represented by the following formula (2):
wherein X 21 is a group containing at least H or C; n 21 is an integer of 1 to 3; Y 21 and Z 21 are the same as or different from each other, and are each a group containing at least H, C, O, or F; n 22 is 0 or 1; and Y 21 and Z 21 optionally bind to each other to form a ring.
5. The electrolyte solution according to claim 4 ,
wherein the compound (2) includes at least one selected from the group consisting of:
a compound (3) represented by the following formula (3):
wherein X 31 to X 34 are the same as or different from each other, and are each a group containing at least H, C, O, or F;
a compound (4) represented by the following formula (4):
wherein X 41 and X 42 are the same as or different from each other, and are each a group containing at least H, C, O, or F; and
phthalic anhydride.
6. An electrochemical device comprising the electrolyte solution according to claim 1 .
7. A lithium ion secondary battery comprising the electrolyte solution according to claim 1 .
8. A module comprising the electrochemical device according to claim 6 .
9. A module comprising the lithium ion secondary battery according to claim 7 .