Electrolyte components of lithium-ion batteries and methods for producing lithium ions

Abstract

The present invention provides an electrolyte component that reduces capacity degradation and impedance increase in lithium-ion batteries during high-temperature storage, and a method for producing lithium ions. [Solution] In one example, the electrolyte component may include vinylene carbonate, fluoroethylene carbonate, 1,3-propanesultone, ethylene sulfite, and a conductive salt containing 80 mol% or more of lithium bis(fluorosulfonyl)imide. In this way, the capacity of the lithium-ion battery can be maintained, such as during high-temperature storage in a 100% charged state.

Claims

1. Electrolyte components, vinylene carbonate (VC), Fluoroethylene carbonate (FEC), 1,3-propanesultone (PS), Ethylene sulfite (ES), and Conductive salts containing 1,3,2-dioxathiolane 2,2-dioxide (DTD), Includes, VC is 0.2 to 5% by weight of the electrolyte component. FEC is 0.5 to 2% by weight of the electrolyte component. PS is 0.1 to 10% by weight of the electrolyte component. ES is 0.2 to 5% by weight of the electrolyte component. DTD is 0.5 to 1.5% by weight of the electrolyte component. An electrolyte component in which LiFSI is present in an amount of 80 mol or more of the conductive salt.

2. The conductive salt is LiPF ６ The electrolyte component according to claim 1, comprising:

3. LiPF ６ The electrolyte component according to claim 2, wherein the amount is 20 mol% or less of the conductive salt.

4. The electrolyte component according to any one of claims 1 to 3, wherein LiFSI is 100 mol% of the conductive salt.

5. LiFSI is 10 to 15% by weight of the electrolyte component, and LiPF ６ However, this is 1 to 5% by weight of the electrolyte component. The electrolyte component according to any one of claims 1 to 3.

6. The electrolyte component according to any one of claims 1 to 4, wherein LiFSI is 12 to 16% by weight of the electrolyte component.

7. VC is 0.5 to 1.5% by weight of the electrolyte component. FEC is 0.5 to 1.5% by weight of the electrolyte component. PS is 0.5 to 1.5% by weight of the electrolyte component, and ES is 0.5 to 1.5% by weight of the electrolyte component. The electrolyte component according to any one of claims 1 to 6.

8. It contains substantially equal amounts of VC, FEC, PES, ES, and DTD. The electrolyte component according to any one of claims 1 to 7.

9. The electrolyte component according to any one of claims 1 to 8, further comprising a non-aqueous solvent selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), ethyl propionate (EP), methyl propionate (MP), and combinations thereof.

10. Cathode, anode, A separator sandwiched between the cathode and the anode, and The electrolyte component according to claim 1, including, Lithium-ion battery.

11. A method for producing lithium ions, Forming electrolyte components, The empty space within the casing of the lithium-ion battery that is not occupied by the cathode, anode, or separator is filled with the electrolyte component that promotes lithium-ion transport between the cathode and the anode. Includes, Forming the aforementioned electrolyte component is Mixing a first conductive salt in a non-aqueous solvent until the first conductive salt is substantially dissolved, wherein the first conductive salt is lithium bis(fluorosulfonyl)imide (LiFSI), and the first conductive salt comprises 80% or more moles of all conductive salts of the electrolyte component. The first additive is mixed in the non-aqueous solvent until the first additive is substantially dissolved. The second additive is mixed in the non-aqueous solvent until the second additive is substantially dissolved. The third additive is mixed in the non-aqueous solvent until the third additive is substantially dissolved. The fourth additive is mixed in the non-aqueous solvent until the fourth additive is substantially dissolved. The fifth additive is mixed in the non-aqueous solvent until the fifth additive is substantially dissolved. Includes, Each of the first to fourth additives comprises one of vinylene carbonate (VC), fluoroethylene carbonate (FEC), 1,3-propanesultone (PS), and ethylene sulfite (ES), and none of the first to fourth additives are the same. The aforementioned electrolyte component is The first conductive salt is 12 to 16% by weight of the electrolyte component. The first additive is present in an amount of 0.5 to 1.5% by weight of the electrolyte component. The second additive is present in an amount of 0.5 to 1.5% by weight of the electrolyte component. The third additive is present in an amount of 0.5 to 1.5% by weight of the electrolyte component. The fourth additive is present in an amount of 0.5 to 1.5% by weight of the electrolyte component, The fourth additive is present in an amount of 0.5 to 1.5% by weight of the electrolyte component. A method for producing lithium ions.

12. The method for producing lithium ions according to claim 11, wherein the non-aqueous solvent is selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), ethyl propionate (EP), methyl propionate (MP), and combinations thereof.

13. Forming the electrolyte component further comprises mixing a second conductive salt in a non-aqueous solvent until the second conductive salt is substantially dissolved, wherein the second conductive salt is lithium hexafluoride phosphate (LiPF4). ６ A method for producing lithium ions according to claim 11 or 12, wherein the method is as follows:

14. The aforementioned electrolyte component is A first component comprising 30 to 50% by weight of the non-aqueous solvent, wherein the first component is EMC. A second component comprising 20 to 30% by weight of the non-aqueous solvent, wherein the second component is EC. A third component comprising 0 to 10% by weight of the non-aqueous solvent, wherein the third component is PC, and A fourth component comprising 0 to 10% by weight of the non-aqueous solvent, wherein the fourth component is DEC. A method for producing lithium ions according to any one of claims 11 to 13, including the method described in any one of claims 11 to 13.

15. The aforementioned electrolyte component is A first component comprising 30 to 50% by weight of the non-aqueous solvent, wherein the first component is EMC. A second component comprising 20 to 30% by weight of the non-aqueous solvent, wherein the second component is EC. A third component comprising 0 to 10% by weight of the non-aqueous solvent, wherein the third component is PC. A fourth component comprising 0 to 10% by weight of the non-aqueous solvent, wherein the fourth component is DEC. A fifth component comprising 5 to 20% by weight of the non-aqueous solvent, wherein the fifth component is DMC, and A sixth component comprising 5 to 20% by weight of the non-aqueous solvent, wherein the sixth component is EP. A method for producing lithium ions according to claim 13, including the method described in claim 13.

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