Power storage device, lithium-ion secondary battery, electric double layer capacitor and lithium-ion capacitor
View Patent ↗One object is to provide a power storage device including an electrolyte using a room-temperature ionic liquid which includes a univalent anion and a cyclic quaternary ammonium cation having excellent reduction resistance. Another object is to provide a high-performance power storage device. A room-temperature ionic liquid which includes a cyclic quaternary ammonium cation represented by a general formula (G1) below is used for an electrolyte of a power storage device. In the general formula (G1), one or two of R 1 to R 5 are any of an alkyl group having 1 to 20 carbon atoms, a methoxy group, a methoxymethyl group, and a methoxyethyl group. The other three or four of R 1 to R 5 are hydrogen atoms. A − is a univalent imide anion, a univalent methide anion, a perfluoroalkyl sulfonic acid anion, tetrafluoroborate (BF 4 − ), or hexafluorophosphate (PF 6 − ).
1. A power storage device comprising:
a positive electrode;
a negative electrode;
a separator;
an electrolyte salt; and
a room-temperature ionic liquid represented by a general formula (G1)
wherein R 2 represents an alkyl group having 1 or 2 carbon atoms,
wherein one of R 1 , R 3 to R 5 represents an alkyl group having 1 or 2 carbon atoms,
wherein the other two of R 1 , and R 3 to R 5 represent hydrogen atoms,
wherein A − represents a univalent imide anion selected from (C n F 2n+1 SO 2 ) 2 N − (n=0 to 4), (C m F 2m+1 SO 3 ) − (m=0 to 4), and CF 2 (CF 2 SO 2 ) 2 N −
and
wherein the electrolyte salt includes a lithium ion.
2. The power storage device according to claim 1 ,
wherein the power storage device is a lithium-ion secondary battery.
3. The power storage device according to claim 1 ,
wherein the power storage device is a lithium-ion capacitor.
4. The power storage device according to claim 1 , wherein the A − is (FSO 2 ) 2 N − or (CF 3 SO 2 ) 2 N − .
5. A power storage device comprising:
a positive electrode;
a negative electrode;
a separator;
an electrolyte salt; and
a room-temperature ionic liquid represented by a general formula (G2)
wherein R 1 represents an alkyl group having 1 or 2 carbon atoms,
wherein R 2 represents a hydrogen atom,
wherein A − represents a univalent imide anion selected from (C n F 2n+1 SO 2 ) 2 N − (n=0 to 4), (C m F 2m+1 SO 3 ) − (m=0 to 4), and CF 2 (CF 2 SO 2 ) 2 N −
and
wherein the electrolyte salt includes a lithium ion.
6. The power storage device according to claim 5 ,
wherein the power storage device is a lithium-ion secondary battery.
7. The power storage device according to claim 5 ,
wherein the power storage device is a lithium-ion capacitor.
8. The power storage device according to claim 5 , wherein the A − is (FSO 2 ) 2 N − or (CF 3 SO 2 ) 2 N − .
9. A power storage device comprising:
a positive electrode;
a negative electrode;
a separator;
an electrolyte salt; and
a room-temperature ionic liquid represented by a general formula (G3)
wherein A − represents a univalent imide anion selected from (C n F 2n+1 SO 2 ) 2 N − (n=0 to 4), (C m F 2m+1 SO 3 ) − (m=0 to 4), and CF 2 (CF 2 SO 2 ) 2 N −
and
wherein the electrolyte salt includes a lithium ion.
10. The power storage device according to claim 9 ,
wherein the power storage device is a lithium-ion secondary battery.
11. The power storage device according to claim 9 ,
wherein the power storage device is a lithium-ion capacitor.
12. The power storage device according to claim 9 , wherein the A − is (FSO 2 ) 2 N − or (CF 3 SO 2 ) 2 N − .