# US 12,009,507 B2 · Methods and systems for salt-rinse surface doping of electrode materials

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 12,009,507 B2
- Document ID: US12009507B2
- Status: Granted
- Kind: B2
- Application number: 17/443,805
- Filed: 2021-07-27
- Published: 2022-02-03
- Granted: 2024-06-11
- Earliest claimed: 2020-07-30
- Assignees: A123 Systems, Inc.
- Applicants: A123 Systems LLC
- Inventors: Lei Liu; Kitae Kim; Lixin Wang; Anil Parmar; Bryan Kim; Chloe Harrison; Andrew Millonig; Derek Johnson; Eunsung Lee; Taehwan Yu
- Web page: https://patentgrep.com/patent/US12009507B2

## CPC

- H01M 4/366: {as layered products}
- C01G 53/502: containing lithium and cobalt
- C01G 53/504: with the molar ratio of nickel with respect to all the metals other than alkali metals higher than or equal to 0.5, e.g. Li(MzNixCoyMn1-x-y-z)O2 with x ≥ 0.5
- C01G 53/506: with the molar ratio of nickel with respect to all the metals other than alkali metals higher than or equal to 0.8, e.g. Li(MzNixCoyMn1-x-y-z)O2 with x ≥ 0.8
- H01M 4/0404: {by coating on electrode collectors}
- H01M 4/0435: {Rolling or calendering}
- H01M 4/049: {Manufacturing of an active layer by chemical means}
- H01M 4/131: Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
- H01M 4/1391: of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
- H01M 4/505: of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
- 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
- C01P 2002/52: containing elements as dopants
- C01P 2004/80: Particles consisting of a mixture of two or more inorganic phases
- C01P 2006/40: Electric properties
- H01M 2004/028: {Positive electrodes}
- Y02E 60/10: Energy storage using batteries
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- C01G: COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts or peroxyacids C01B15/00; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium, or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds containing nitrogen, other non-metals and metal C01B21/082}; metal amides C01B21/092; nitrites C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; compounds having molecular sieve properties but not having base-exchange properties C01B37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, C01B39/00; cyanides C01C3/08; salts of cyanamide C01C3/16; thiocyanates C01C3/20)
- C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION

## Abstract

Methods and systems are provided for salt-rinse surface doping of electrode materials for lithium-ion batteries. In one example, a method may include dissolving a dopant salt in a solvent to form a dopant salt rinse solution, rinsing an electrode active material with the dopant salt rinse solution to form a coated electrode active material, and heating the coated electrode active material to form a doped electrode active material. In some examples, a surface region of the doped electrode active material may include a uniform distribution of dopants from the dopant salt rinse solution. In this way, the electrode active material may be rinsed and doped via the dopant salt rinse solution in a single-stage process.

## Claims

### Claim 1

A method, comprising:
dissolving a dopant salt in a rinsing solvent to form a dopant salt rinse solution;
rinsing an electrode active material with the dopant salt rinse solution to obtain a uniformly surface-coated electrode active material, wherein rinsing the electrode active material with the dopant salt rinse solution to obtain the uniformly surface-coated electrode active material comprises:
mixing the electrode active material with the dopant salt rinse solution to form a mixture, wherein mixing the electrode active material with the dopant salt rinse solution comprises:
dissolving a residual lithium salt on a surface of the electrode active material; and
precipitating a dopant precipitate on the surface of the electrode active material while producing a product salt, where the dopant precipitate is formed from a cation of the dopant salt and an anion of the residual lithium salt, where the product salt is formed from lithium and an anion of the dopant salt is soluble in the dopant salt rinse solution, and where the dopant precipitate has a lower solubility in the dopant salt rinse solution than each of the residual lithium salt and the product salt;
filtering the mixture to isolate a filtrate; and
drying the filtrate to obtain the uniformly surface-coated electrode active material; and
heating the uniformly surface-coated electrode active material to form a uniformly surface-doped electrode active material.

### Claim 2 (depends on 1)

The method of claim 1, wherein the dopant salt comprises cations of any one of Al, Mg, Mn, Co, Ni, Ti, Zr, Sn, Cu, Ca, La, Ce, Y, Nd, W, Na, K, V, Nb, Mo, Fe, Zn, F, Cl, Br, S, Se, P, Sb, Si, Ge, Ga, and B, or a combination thereof.

### Claim 3 (depends on 1)

The method of claim 1, wherein the dopant salt comprises cations of any one of Al, Mg, Mn, Co, Ni, Ti, Zr, W, F, and B, or a combination thereof.

### Claim 4 (depends on 2)

The method of claim 2, wherein a surface region of the uniformly surface-doped electrode active material comprises a uniform distribution of the cations.

### Claim 5 (depends on 2)

The method of claim 2, wherein the cations are included in the uniformly surface-doped electrode active material at 0.1 to 2 mol %.

### Claim 6 (depends on 1)

The method of claim 1, wherein cations of Mn and/or cations of Co are included in the dopant salt, and wherein the cations are included in the uniformly surface-doped electrode active material at 0.1 to 15 mol %.

### Claim 7 (depends on 1)

The method of claim 1, wherein the dopant salt comprises one or more dopant oxides, one or more dopant acetates, one or more dopant nitrides, one or more dopant sulfates, one or more dopant fluorides, one or more dopant nitrates, one or more dopant phosphides, one or more dopant sulfides, one or more dopant iodides, one or more dopant phosphates, one or more dopant carbonates, one or more dopant oxalates, one or more dopant acetylacetones, or a combination thereof.

### Claim 8 (depends on 1)

The method of claim 1, wherein the electrode active material comprises one or more lithium insertion electrode materials.

### Claim 9 (depends on 1)

The method of claim 1, wherein the electrode active material is a cathode active material comprising stoichiometric NMC, lithium-rich NMC, NCA, NCMA, LNO, spinel LMO, spinel LNMO, LFP, or a combination thereof.

### Claim 10 (depends on 1)

The method of claim 1, wherein the uniformly surface-doped electrode active material is NMC or doped NMC.

### Claim 11 (depends on 1)

The method of claim 1, wherein the electrode active material is an anode active material comprising LTO, graphite, graphene, silicon, a silicon oxide, a tin oxide, or a combination thereof.

### Claim 12 (depends on 1)

The method of claim 1, wherein the rinsing solvent comprises water, ethanol, methanol, isopropanol, acetone, acetone nitrile, ethyl acetate, ethylene glycol, or a combination thereof.

### Claim 13

A method, comprising:
dissolving a metal salt in a rinsing solvent to form an aqueous rinse solution; and thereafter,
mixing a cathode active material with the aqueous rinse solution to form a mixture, wherein mixing the cathode active material with the aqueous rinse solution comprises:
dissolving a residual lithium salt on a surface of the cathode active material; and
precipitating a dopant precipitate on the surface of the cathode active material while producing a product salt, where the dopant precipitate is formed from a cation of the metal salt and an anion of the residual lithium salt, where the product salt is formed from lithium and an anion of the metal salt is soluble in the rinsing solvent, and where the dopant precipitate has a lower solubility in the rinsing solvent than each of the residual lithium salt and the product salt; and thereafter,
without any further rinsing:
isolating a coated cathode active material from the rinsing solvent, the rinsing solvent including dissolved Lit;
heating the coated cathode active material to obtain a surface-doped cathode active material; and
forming a cathode slurry comprising the surface-doped cathode active material.

### Claim 14 (depends on 13)

The method of claim 13, wherein the metal salt is a salt of any one of Al, Mg, Mn, Co, Ni, Ti, Zr, W, F, and B, or a combination thereof.

### Claim 15 (depends on 13)

The method of claim 13, wherein the cathode active material comprises an NMC having a molar content of nickel of 60% or greater of a total molar content of nickel, manganese, and cobalt.