Lithium-ion battery, battery, and electric apparatus

Patent metadata

Field	Value
Publication number	US-12548802-B2
Application number	US-202418800152-A
Country	US
Kind code	B2
Filing date	Aug 12, 2024
Priority date	Oct 30, 2023
Publication date	Feb 10, 2026
Grant date	Feb 10, 2026

Abstract

This application relates to a lithium-ion battery, a battery, and an electric apparatus. The lithium-ion battery includes an electrolyte and a positive electrode plate. The electrolyte includes lithium salt, the lithium salt includes lithium hexafluorophosphate, and a mass proportion of the lithium hexafluorophosphate relative to a total mass of the electrolyte is 15% to 20%. The positive electrode plate includes a positive electrode current collector and a positive electrode film layer disposed on at least one side of the positive electrode current collector and containing a positive electrode active material. This application can improve cycling performance of the lithium-ion battery.

First claim

What is claimed is:

1 . A lithium-ion battery, comprising:
an electrolyte, comprising lithium salt, wherein the lithium salt comprises lithium hexafluorophosphate, and a mass proportion of the lithium hexafluorophosphate relative to a total mass of the electrolyte is 15% to 20%; a positive electrode plate, comprising a positive electrode current collector and a positive electrode film layer disposed on at least one side of the positive electrode current collector and containing a positive electrode active material, wherein the positive electrode active material comprises a compound with a molecular formula Li d Ni a Co b Mn c M (1-a-b-c) Q z , wherein 0<d≤2.1, 0.6<a<1, 0<b><1, 0<<<1, 0.6<a+b+c<1, and 1.8<z<3.5; element M comprises at least one of elements Ti and Zr; and element Q comprises at least one of elements O and F; wherein, the positive electrode active material comprises single crystal particles, the single crystal particle comprises an inner region and an outer region, wherein the outer region is a region extending 500 nm directly from any point on an outer surface of the single crystal particle toward inside of the single crystal particle; element M comprises element Al, wherein elements Al are distributed at least in the outer region, element M further comprises at least one of elements P, S, and B, wherein at least one of elements P, S, and B is distributed in the outer region; and the electrolyte comprises a first additive and a third additive, wherein the first additive comprises at least one of lithium difluoroxalate borate LiDFOB and lithium tetrafluoroborate LiBF 4 , the third additive comprises lithium fluorosulfonate.

2 . The lithium-ion battery according to claim 1 , wherein
element M further comprises at least one of elements B, Mg, Al, Si, P, S, Ca, Sc, V, Cr, Fe, Cu, Zn, Sr, Y, Nb, Mo, Cd, Sn, Sb, Te, Ba, Ta, W, Yb, La, and Ce.

3 . The lithium-ion battery according to claim 1 , wherein
based on the total mass of the electrolyte, a mass proportion of the first additive is 30 ppm to 1200 ppm; based on a total mass of the positive electrode active material, a mass proportion of element Ti is 100 ppm to 600 ppm; and/or based on the total mass of the positive electrode active material, a mass proportion of element Zr is 500 ppm to 2550 ppm.

4 . The lithium-ion battery according to claim 1 , wherein
the electrolyte comprises a second additive, wherein the second additive comprises lithium difluorophosphate.

5 . The lithium-ion battery according to claim 4 , wherein
based on the total mass of the positive electrode active material, a mass proportion of element Al is 500 ppm to 3000 ppm; and based on the total mass of the electrolyte, a mass proportion of the second additive is 100 ppm to 3000 ppm.

6 . The lithium-ion battery according to claim 1 , wherein
based on the total mass of the positive electrode active material, a total mass proportion of elements P, S, and B is 10 ppm to 800 ppm; and based on the total mass of the electrolyte, a mass proportion of the third additive is 50 ppm to 200 ppm.

7 . The lithium-ion battery according to claim 1 , wherein
the electrolyte comprises cyclic carbonate, and based on the total mass of the electrolyte, a ratio of a mass proportion of the cyclic carbonate to the mass proportion of the lithium hexafluorophosphate is (0.60-2.50):1.

8 . The lithium-ion battery according to claim 7 , wherein
based on the total mass of the electrolyte, the ratio of the mass proportion of the cyclic carbonate to the mass proportion of the lithium hexafluorophosphate is (1.00-1.65):1.

9 . The lithium-ion battery according to claim 7 , wherein
based on the total mass of the electrolyte, the mass proportion of the cyclic carbonate is 20% to 30%; and/or the cyclic carbonate comprises at least one of ethylene carbonate EC, propylene carbonate PC, and butylene carbonate BC.

10 . The lithium-ion battery according to claim 1 , wherein the lithium-ion battery further comprises a negative electrode plate, wherein the negative electrode plate comprises a negative electrode current collector and a negative electrode film layer disposed on at least one side of the negative electrode current collector and containing a negative electrode active material, the negative electrode active material comprises element carbon and element silicon, and based on a total mass of the negative electrode active material, a ratio of a mass proportion of the element silicon to a mass proportion of the element carbon is (0.3:99.7) to (3:97).

11 . The lithium-ion battery according to claim 10 , wherein
the electrolyte comprises fluorinated cyclic carbonate, and a ratio of a mass proportion of the fluorinated cyclic carbonate relative to the total mass of the electrolyte to the mass proportion of the element silicon is (0.5-9.5):1.

12 . The lithium-ion battery according to claim 11 , wherein
the ratio of the mass proportion of the fluorinated cyclic carbonate relative to the total mass of the electrolyte to the mass proportion of the element silicon is (1-2):1.

13 . The lithium-ion battery according to claim 11 , wherein based on the total mass of the electrolyte, the mass proportion of the fluorinated cyclic carbonate is 0.95% to 5.8%; and/or
the fluorinated cyclic carbonate comprises at least one of monofluoroethylene carbonate FEC, difluoroethylene carbonate DFEC, and trifluoropropylene carbonate TFPC.

14 . The lithium-ion battery according to claim 13 , wherein
based on the total mass of the electrolyte, the mass proportion of the fluorinated cyclic carbonate is 1.5% to 3%; and/or the fluorinated cyclic carbonate comprises monofluoroethylene carbonate FEC.

15 . The lithium-ion battery according to claim 10 , wherein
a ratio of a press density of the positive electrode film layer to a press density of the negative electrode film layer is (2-2.5):1.

16 . The lithium-ion battery according to claim 1 , wherein
the electrolyte further comprises a fourth additive, and the fourth additive comprises at least one of 1,3-propane sultone PS, vinylene carbonate VC, and lithium fluorosulfonate LiSO 3 F.

17 . The lithium-ion battery according to claim 16 , wherein
based on the total mass of the electrolyte, a mass proportion of the 1,3-propane sultone PS is 0.1% to 1%; and/or based on the total mass of the electrolyte, a mass proportion of the vinylene carbonate VC is 0.1% to 1%.

18 . A battery, comprising the lithium-ion battery according to claim 1 .

19 . An electric apparatus, comprising the battery according to claim 18 .

Assignees

• Contemporary Amperex Technology Co Ltd

Inventors

• Wu Zeli
• Han Changlong
• Jiang Bin
• Guo Jie

Classifications

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M10/0568 Primary

  characterised by the solutes · CPC title

• H01M2300/004

  Three solvents · CPC title

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title