US-20260128284-A1 - BATTERY ELECTRODE

Abstract

A battery includes, in one example, a positive electrode and a negative electrode, where the negative electrode includes active material flakes with hydroxylated edges surrounding non-hydroxylated planes. Hydroxylated metal oxide nanoparticles are chemisorbed to the hydroxylated edges, selectively coating these regions. The metal oxide nanoparticles may be tungsten, niobium, or aluminum.

Inventors

• Shiran Zhang
• Michael Lerner
• Sookyung Jeong

Assignees

• FORD GLOBAL TECHNOLOGIES, LLC

Dates

Publication Date

20260507

Application Date

20241107

Claims (20)

1. 1 . A battery comprising: a positive electrode; and a negative electrode including active material flakes defining hydroxylated edges surrounding non-hydroxylated planes, and hydroxylated metal oxide nanoparticles chemisorbed to the hydroxylated edges and selectively coating the hydroxylated edges.
2. 2 . The battery of claim 1 wherein the active material flakes are graphite-based.
3. 3 . The battery of claim 1 wherein the metal oxide nanoparticles are selected from a group comprising oxides of tungsten, niobium, and aluminum.
4. 4 . The battery of claim 1 wherein the metal oxide nanoparticles are covalently bonded to the hydroxylated edges of the negative electrode.
5. 5 . The battery of claim 1 wherein the metal oxide nanoparticles have an average particle size between 5 nm and 100 nm.
6. 6 . The battery of claim 1 wherein the metal oxide nanoparticles form a uniform coating layer at the hydroxylated edges of the active material flakes.
7. 7 . The battery of claim 6 wherein the coating has a thickness between 20 nm and 200 nm.
8. 8 . An electrode assembly comprising: a current collector; and a graphite-based active material layer, with active material flakes defining hydroxylated edges surrounding non-hydroxylated planes, and metal oxide nanoparticles chemically bonded to the hydroxylated edges of the active material flakes and selectively coating the hydroxylated edges.
9. 9 . The electrode assembly of claim 8 wherein the metal oxide nanoparticles are amorphous metal oxides.
10. 10 . The electrode assembly of claim 8 wherein the metal oxide nanoparticles are selected from a group comprising oxides of tungsten, niobium, and aluminum.
11. 11 . The electrode assembly of claim 8 wherein non-hydroxylated planes of the graphite-based active material layer are free of metal oxide nanoparticles.
12. 12 . The electrode assembly of claim 8 wherein the metal oxide nanoparticles are covalently bonded to the hydroxylated edges of the graphite-based active material layer.
13. 13 . The electrode assembly of claim 8 wherein the metal oxide nanoparticles have an average particle size between 5 nm and 100 nm.
14. 14 . The electrode assembly of claim 8 wherein the metal oxide nanoparticles form a continuous layer at the hydroxylated edges of the graphite-based active material layer.
15. 15 . A method of forming an electrode material comprising: applying a hydroxide to a graphite-based active material to form a hydroxide-treated graphite-based active material with hydroxyl groups at edge sites; dispersing the hydroxide-treated graphite-based active material in a non-polar solvent with a metal chloride precursor to form a graphite-based active material solution; adding a metal chloride precursor solution into the graphite-based active material solution; and calcining resulting material collected from the graphite-based active material solution to remove chlorine and form amorphous metal oxide nanoparticles selectively anchored at edge sites of the graphite-based active material.
16. 16 . The method of claim 15 , further comprising drying the hydroxide-treated graphite-based active material in a vacuum to remove water before dispersing in the non-polar solvent.
17. 17 . The method of claim 15 wherein the non-polar solvent is a hydrocarbon solvent.
18. 18 . The method of claim 15 wherein the metal chloride precursor is selected from a group comprising tungsten hexachloride, niobium pentachloride, and aluminum trichloride.
19. 19 . The method of claim 15 wherein calcining is performed at 150° C.
20. 20 . The method of claim 15 , further comprising collecting the resulting material using vacuum filtration before calcining.

Description

TECHNICAL FIELD This disclosure relates to electrodes for lithium-ion batteries. BACKGROUND Fast charging capability is a factor for practical lithium-ion battery applications, driving ongoing research. Coating anodes may increase the charging speed of lithium-ion batteries. SUMMARY A battery includes a positive electrode and a negative electrode including active material flakes defining hydroxylated edges surrounding non-hydroxylated planes and hydroxylated metal oxide nanoparticles chemisorbed to the hydroxylated edges and selectively coating the hydroxylated edges. The active material flakes may be graphite-based. The metal oxide nanoparticles may be selected from a group that comprises oxides of tungsten, niobium, and aluminum. The metal oxide nanoparticles may be covalently bonded to the hydroxylated edges of the negative electrode. The metal oxide nanoparticles may have an average particle size between 5 nm and 100 nm. The metal oxide nanoparticles may form a uniform coating layer at the hydroxylated edges of the active material flakes. The ring coating may have a thickness between 20 nm and 200 nm. An electrode assembly includes a current collector, and a graphite-based active material layer, with active material flakes defining hydroxylated edges surrounding non-hydroxylated planes, and metal oxide nanoparticles chemically bonded to the hydroxylated edges of the active material flakes, forming a selective coating around the hydroxylated edges. The metal oxide nanoparticles may be amorphous metal oxides. The metal oxide nanoparticles may be selected from a group of oxides that comprises tungsten, niobium, and aluminum. The non-hydroxylated planes of the graphite-based active material layer may be substantially free of metal oxide nanoparticles. The metal oxide nanoparticles may be covalently bonded to the hydroxylated edges of the graphite-based active material layer. The metal oxide nanoparticles may have an average particle size between 5 nm and 100 nm. The metal oxide nanoparticles may form a continuous layer at the terminal surfaces of the graphite-based active material layer. A method of forming an electrode material includes applying a hydroxide to a graphite-based active material to form a hydroxide-treated graphite-based active material with hydroxyl groups at edge sites, dispersing the hydroxide-treated graphite-based active material in a non-polar solvent with a metal chloride precursor to form a graphite-based active material solution, adding a metal chloride precursor solution into the graphite-based active material solution, and calcining resulting material collected from the graphite-based active material solution to remove chlorine and form amorphous metal oxide nanoparticles selectively anchored at edge sites of the graphite-based active material. The method may further include drying the hydroxide-treated graphite-based active material in a vacuum to remove water before dispersing in the non-polar solvent. The non-polar solvent may be a hydrocarbon solvent. The metal chloride precursor may be selected from a group that comprises tungsten hexachloride, niobium pentachloride, and aluminum trichloride. The calcining may be performed at 150° C. The method may further include collecting the resulting material using vacuum filtration before calcining. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a conventional electrode coating; FIGS. 2-3 are images of selective coatings at electrode edges; FIG. 4 is a schematic diagram of selective coating at electrode edges; and FIG. 5 is a flowchart of a method to form a ring-coated electrode. DETAILED DESCRIPTION In accordance with the present disclosure, embodiments of electrode structures, manufacturing methods, and battery systems are described herein. These embodiments illustrate innovative techniques for enhancing lithium-ion battery performance by modifying graphite-based active material flakes with hydroxylated edges and incorporating metal oxide nanoparticles, such as those selected from oxides of tungsten, niobium, or aluminum, which chemisorb to the hydroxylated edges. The figures and descriptions provided are exemplary and do not represent every possible variation or configuration. Certain elements may be emphasized or minimized to clarify specific features of the electrode assemblies and their formation processes. Accordingly, the disclosed structural and functional details are not intended to limit the scope of the invention but to provide guidance to those skilled in the art of implementing various embodiments of the claimed subject matter. Unless specifically stated otherwise, all numerical values, measurements, percentages, and similar quantitative parameters disclosed should be interpreted as being prefaced with “about.” This includes any figures regarding porosity, particle size, coating thickness, and calcination temperatures. The use of “about” accounts for variations due to measurement techniques, manufacturin