Nonaqueous Electrolytic Solution and Nonaqueous Electrolytic Solution Secondary Battery

• US 20190312307A1
• Filed: 07/04/2017
• Published: 10/10/2019
• Est. Priority Date: 07/06/2016
• Status: Active Grant

• Current Assignee: Central Glass Company Limited
• Original Assignee: Central Glass Company Limited
• Inventors: ITABASHI, Saori, HARADA, Shuji, SUZUKI, Katsutoshi, TAKEDA, Kazunari
• Granted Patent: US 11,101,499 B2
• Time in Patent Office: Days
• CPC Class Codes: C07F 9/65748 the cyclic phosphorus atom belonging to more than one ring system
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0567 characterised by the additives
• CPC Class Codes: H01M 10/0568 characterised by the solutes
• CPC Class Codes: H01M 10/0569 characterised by the solvents
• CPC Class Codes: H01M 2300/0025 Organic electrolyte
• CPC Class Codes: H01M 2300/0037 Mixture of solvents
• CPC Class Codes: H01M 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 4/387 Tin or alloys based on tin
• CPC Class Codes: H01M 4/485 of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy H01M4/505, H01M4/525 take precedence
• CPC Class Codes: H01M 4/505 of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: H01M 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: H01M 50/417 Polyolefins
• CPC Class Codes: H01M 50/429 Natural polymers
• CPC Class Codes: H01M 50/4295 Natural cotton, cellulose or wood
• CPC Class Codes: H01M 50/44 Fibrous material
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

An object of the present invention is to provide a nonaqueous electrolytic solution and a nonaqueous electrolytic solution secondary battery capable of showing high output characteristics at a low temperature even after the battery is used to some extent, and capable of showing good high-rate properties, and further capable of improving safety of batteries. The nonaqueous electrolytic solution includes a nonaqueous solvent, an electrolyte dissolved in the nonaqueous solvent, (I) a difluoro ionic complex (1) represented by the general formula (1), and (II) at least one compound selected from the group consisting of a specific cyclic phosphazene compound, siloxane compound, aromatic compound, cyclohexene compound, phosphoric acid ester compound, fluorinated linear ether compound, fluorinated cyclic ether compound, and boric acid ester compound, and 95 mol % or more of the difluoro ionic complex (1) is a difluoro ionic complex (1-Cis) in a cis configuration represented by the general formula (1-Cis).

Claims

1. A nonaqueous electrolytic solution for nonaqueous electrolytic solution secondary batteries, the nonaqueous electrolytic solution comprising:

a nonaqueous solvent,

an electrolyte dissolved in the nonaqueous solvent,

(I) a difluoro ionic complex (1) represented by the general formula (1), and

(II) at least one compound selected from the group consisting of a cyclic phosphazene compound represented by the general formula (II-1) below, a siloxane compound represented by the general formula (II-2) below, an aromatic compound represented by the general formula (II-3) below, a cyclohexene compound represented by the general formula (II-4) below, a phosphoric acid ester compound represented by the general formula (II-5) below, a fluorinated linear ether compound represented by the general formula (II-6) below, a fluorinated cyclic ether compound represented by the general formula (II-7) below, and a boric acid ester compound represented by the general formula (II-8) below,

wherein 95 mol % or more of the difluoro ionic complex (1) is a difluoro ionic complex (1-Cis) in a cis configuration represented by the general formula (1-Cis),

2. The nonaqueous electrolytic solution according to claim 1, wherein a combination of M, X, Y, W, p, q, r, and tin an anion moiety of the difluoro ionic complex (1) and in an anion moiety of the difluoro ionic complex (1-Cis) is at least one combination selected from (Cis-a), (Cis-b), (Cis-c), and (Cis-d):

(Cis-a) M=P;

X=O;

Y=C;

p=q=t=1; and

r=0;

(Cis-b) M=P;

X=O;

W=C(CF₃)₂;

p=q=0; and

r=t=1;

(Cis-c) M=Si;

X=O;

Y=C;

p=q=1;

t=2; and

r=0; and

(Cis-d) M=P;

X=N(R¹);

Y=C;

R¹=CH₃;

p=q=t=1; and

r=0.

3. The nonaqueous electrolytic solution according to claim 1, wherein the A⁺ in the difluoro ionic complex (1-Cis) comprises at least one selected from the group consisting of a lithium ion, a sodium ion, a potassium ion, and a quaternary alkylammonium ion.

4. The nonaqueous electrolytic solution according to claim 1, wherein the content of the difluoro ionic complex (1-Cis) is in the range of 0.001 mass % or more and 20 mass % or less relative to the nonaqueous electrolytic solution.

5. The nonaqueous electrolytic solution according to claim 1, wherein

the content of the compound shown in the (II) above is in the range of 0.01 mass % or more and 50 mass % or less relative to the nonaqueous electrolytic solution,

in the case where the compound shown in the (II) above comprises a cyclic phosphazene compound represented by the general formula (II-1) above, the content of the cyclic phosphazene compound represented by the general formula (II-1) above is in the range of 0.5 mass % or more and 15 mass % or less relative to the nonaqueous electrolytic solution,

in the case where the compound shown in the (II) above comprises a siloxane compound represented by the general formula (II-2) above, the content of the siloxane compound represented by the general formula (II-2) above is in the range of 0.01 mass % or more and 10 mass % or less relative to the nonaqueous electrolytic solution,

in the case where the compound shown in the (II) above comprises an aromatic compound represented by the general formula (II-3) above, the content of the aromatic compound represented by the general formula (II-3) above is in the range of 0.01 mass % or more and 10 mass % or less relative to the nonaqueous electrolytic solution,

in the case where the compound shown in the (II) above comprises a cyclohexene compound represented by the general formula (II-4) above, the content of the cyclohexene compound represented by the general formula (II-4) above is in the range of 0.01 mass % or more and 10 mass % or less relative to the nonaqueous electrolytic solution,

in the case where the compound shown in the (II) above comprises a phosphoric acid ester compound represented by the general formula (II-5) above, the content of the phosphoric acid ester compound represented by the general formula (II-5) above is in the range of 5 mass % or more and 40 mass % or less relative to the nonaqueous electrolytic solution,

in the case where the compound shown in the (II) above comprises a fluorinated linear ether compound represented by the general formula (II-6) above, the content of the phosphoric acid ester compound represented by the general formula (II-6) above is in the range of 10 mass % or more and 50 mass % or less relative to the nonaqueous electrolytic solution,

in the case where the compound shown in the (II) above comprises a fluorinated cyclic ether compound represented by the general formula (II-7) above, the content of the fluorinated cyclic ether compound represented by the general formula (II-7) above is in the range of 10 mass % or more and 50 mass % or less relative to the nonaqueous electrolytic solution, and

in the case where the compound shown in the (II) above comprises a boric acid ester compound represented by the general formula (II-8) above, the content of the boric acid ester compound represented by the general formula (II-8) above is in the range of 3 mass % or more and 30 mass % or less relative to the nonaqueous electrolytic solution.

6. The nonaqueous electrolytic solution according to claim 1, wherein the difluoro ionic complex (1) further comprises (III) a difluoro ionic complex (1-Trans) in a trans configuration represented by the general formula (1-Trans),

7. The nonaqueous electrolytic solution according to claim 6, wherein a combination of M, X, Y, W, p, q, r, and tin an anion moiety of the difluoro ionic complex (1-Trans) is at least one combination selected from (Trans-a), (Trans-b), (Trans-c), and (Trans-d) below:

(Trans-a) M=P;

X=O;

Y=C;

p=q=t=1; and

r=0,

(Trans-b) M=P;

X=O;

W=C(CF₃)₂;

p=q=0; and

r=t=1,

(Trans-c) M=Si;

X=O;

Y=C;

p=q=1;

t=2; and

r=0; and

(Trans-d) M=P;

X=N(R¹);

Y=C;

R¹=CH₃;

p=q=t=1; and

r=0.

8. The nonaqueous electrolytic solution according to claim 6, wherein the A⁺ in the difluoro ionic complex (1-Trans) comprises at least one selected from the group consisting of a lithium ion, a sodium ion, a potassium ion, and a quaternary alkylammonium ion.

9. The nonaqueous electrolytic solution according to claim 6, wherein the mass ratio (1-Trans)/(1-Cis) of the difluoro ionic complex (1-Trans) to the difluoro ionic complex (1-Cis) is 0.0001 or more and 0.05 or less.

10. The nonaqueous electrolytic solution according to claim 1, further comprising (IV) a tetrafluoro ionic complex represented by the general formula (1-Tetra):

11. The nonaqueous electrolytic solution according to claim 10, wherein a combination of M, X, Y, W, p, q, r, and t in an anion moiety of the tetrafluoro ionic complex is at least one combination selected from (Tetra-a), (Tetra-b), (Tetra-c), and (Tetra-d):

(Tetra-a) M=P;

X=O;

Y=C;

p=q=t=1; and

r=0,

(Tetra-b) M=P;

X=O;

W=C(CF₃)₂;

p=q=0; and

r=t=1,

(Tetra-c) M=Si;

X=O;

Y=C;

p=q=1;

t=2; and

r=0; and

(Tetra-d) M=P;

X=N(R¹);

Y=C;

R¹=CH₃;

p=q=t=1; and

r=0.

12. The nonaqueous electrolytic solution according to claim 10, wherein the A⁺ in the tetrafluoro ionic complex (1-Tetra) comprises at least one selected from the group consisting of a lithium ion, a sodium ion, a potassium ion, and a quaternary alkylammonium ion.

13. The nonaqueous electrolytic solution according to claim 10, wherein the mass ratio (1-Tetra)/(1-Cis) of the tetrafluoro ionic complex (1-Tetra) to the difluoro ionic complex (1-Cis) is 0.02 or more and 0.25 or less.

14. The nonaqueous electrolytic solution according to claim 1, wherein the nonaqueous solvent comprises at least one selected from the group consisting of a cyclic carbonate and a chain carbonate.

15. The nonaqueous electrolytic solution according to claim 14, wherein the cyclic carbonate comprises at least one selected from the group consisting of ethylene carbonate and propylene carbonate, and

the chain carbonate comprises at least one selected from the group consisting of ethylmethyl carbonate, dimethyl carbonate, diethyl carbonate, and methylpropyl carbonate.

16. The nonaqueous electrolytic solution according to claim 14, wherein the nonaqueous solvent further comprises at least one selected from the group consisting of esters, ethers, lactones, nitriles, amides, and sulfones.

17. The nonaqueous electrolytic solution according to claim 14, wherein the nonaqueous solvent further comprises at least one compound selected from the group consisting of vinylene carbonate, vinylethylene carbonate, ethynylethylene carbonate, and fluoroethylene carbonate.

18. The nonaqueous electrolytic solution according to claim 1, wherein the electrolyte comprises a salt comprising a pair of a cation and an anion, the cation being at least one selected from the group consisting of lithium, sodium, potassium, and quaternary ammonium, and the anion being at least one selected from the group consisting of hexafluorophosphoric acid, tetrafluoroboric acid, perchloric acid, hexafluoroarsenic acid, hexafluoroantimonic acid, trifluoromethanesulfonic acid, bis(trifluoromethanesulfonyl)imide, bis(pentafluoroethanesulfonyl)imide, (trifluoromethanesulfonyl)(pentafluoroethanesulfonyl)imide, bis(fluorosulfonyl)imide, (trifluoromethanesulfonyl)(fluorosulfonyl)imide, (pentafluoroethanesulfonyl)(fluorosulfonyl)imide, tris(trifluoromethanesulfonyl)methide, and bis(difluorophosphonyl)imide.

19. A nonaqueous electrolytic solution secondary battery comprising the nonaqueous electrolytic solution according to claim 1, a positive electrode, a negative electrode, and a separator.

20. A nonaqueous electrolytic solution secondary battery, comprising:

(a) the nonaqueous electrolytic solution according to claim 1;

(b) a positive electrode including at least one of oxide and a polyanion compound as a positive-electrode active material;

(c) a negative electrode including a negative-electrode active material; and

(d) a separator including polyolefin or cellulose as a main component,

wherein the positive-electrode active material is at least one selected from the group consisting of (A) a lithium-transition metal composite oxide containing at least one metal of nickel, manganese, and cobalt, and having a layered structure, (B) a lithium-manganese composite oxide having a spinel structure, (C) a lithium-containing olivine-type phosphate salt, and (D) a lithium-rich layered transition-metal oxide having a stratified rock-salt structure, and

the negative-electrode active material is at least one selected from the group consisting of (E) a carbon material having a d value in a lattice plane (002) of 0.340 nm or less as determined by X ray diffraction, (F) a carbon material having a d value in the lattice plane (002) of more than 0.340 nm as determined by X ray diffraction, (G) an oxide of one or more metals selected from Si, Sn, and Al, (H) one or more metals selected from Si, Sn, and Al, and an alloy comprising the one or more metals and further comprising or not comprising lithium, and (I) a lithium titanium oxide.