# US 10,483,529 B2 · Composite powder for use in an anode of a lithium ion battery, method of preparing such a composite powder and method for analysing such a composite powder

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

- Number: US 10,483,529 B2
- Document ID: US10483529B2
- Status: Granted
- Kind: B2
- Application number: 15/538,706
- Filed: 2015-12-11
- Published: 2017-12-07
- Granted: 2019-11-19
- Earliest claimed: 2014-12-23
- Assignees: Umicore AG & Co. KG; Showa Denko K.K.
- Applicants: Umicore; Showa Denko K.K.
- Inventors: Stijn Put; Dirk Van Genechten; Kris Driesen; Jin Hu; Yvan Strauven; Arihiro Muto; Nobuaki Ishii; Masataka Takeuchi
- Web page: https://patentgrep.com/patent/US10483529B2

## CPC

- H01M 4/364: {as mixtures}
- H01M 4/386: {Silicon or alloys based on silicon}
- H01M 4/625: {Carbon or graphite}
- H01M 10/0413: {Large-sized flat cells or batteries for motive or stationary systems with plate-like electrodes}
- H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
- Y02E 60/10: Energy storage using batteries
- Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

Composite powder for use in an anode of a lithium ion battery, whereby the particles of the composite powder comprise silicon-based domains in a matrix, whereby the individual silicon-based domains are either free silicon-based domains that are not or not completely embedded in the matrix or are fully embedded silicon-based domains that are completely surrounded by the matrix, whereby the percentage of free silicon-based domains is lower than or equal to 4 weight % of the total amount of Si in metallic or oxidized state in the composite powder.

## Claims

### Claim 1

A composite powder for use in an anode of a lithium ion battery, wherein particles of the composite powder comprise silicon-based domains in a matrix, and wherein the matrix comprises carbon or a precursor material that can be converted into carbon by thermal treatment, and wherein the individual silicon-based domains are either:
free silicon-based domains that are not or not completely embedded in the matrix, or
fully embedded silicon-based domains that are completely surrounded by the matrix,
wherein the percentage of free silicon-based domains is lower than or equal to 4 weight % of the total amount of Si in metallic or oxidized state in the composite powder, and
wherein the silicon-based domains have a weight based size distribution with a d50 of 200 nm or less and a d90 of 1000 nm or less, and wherein the composite powder also comprises graphite, wherein the graphite is not embedded in the matrix.

### Claim 2 (depends on 1)

The composite powder according to claim 1, wherein the percentage of free silicon-based domains is lower than 3 weight % of the total amount of Si in metallic or oxidised state in the composite powder.

### Claim 3 (depends on 1)

The composite powder according to claim 1, wherein the percentage of free silicon-based domains is the percentage as determined by placing a sample of the composite powder in an alkaline solution for a specified time, determining the volume of hydrogen that has evolved after the specified time, calculating the amount of silicon needed for evolving this amount of hydrogen based on a production of two moles of hydrogen for every mole of silicon reacted and dividing this by the total amount of Si in metallic or oxidised state present in the sample.

### Claim 4 (depends on 1)

The composite powder according to claim 1, wherein the powder contains less than 3 weight % of oxygen.

### Claim 5 (depends on 1)

The composite powder according to claim 1, wherein the powder contains between 2 weight % and 25 weight % of Si.

### Claim 6 (depends on 1)

The composite powder according to claim 1, wherein the matrix comprises pitch or thermally decomposed pitch.

### Claim 7 (depends on 1)

The composite powder according to claim 1, wherein the silicon-based domains are silicon-based particles.

### Claim 8 (depends on 1)

The composite powder according to claim 1, wherein the powder has an average particle diameter d50 of between 1 and 20 microns.

### Claim 9 (depends on 1)

The composite powder according to claim 1, wherein at least 97% of the surface area of the silicon-based domains is covered by the matrix.

### Claim 10 (depends on 1)

The composite powder according to claim 1, wherein the silicon-based domains have a weight-based size distribution with a d50 of 100 nm or less and a d90 of 1000 nm or less.

### Claim 11 (depends on 1)

The composite powder according to claim 1, wherein a ratio between an average size of the composite powder and a d50 of the silicon-based domains is 10 or more.