Active material with expansion structure for use in lithium ion batteries

Patent metadata

Field	Value
Publication number	US-10319987-B2
Application number	US-201514975896-A
Country	US
Kind code	B2
Filing date	Dec 21, 2015
Priority date	Dec 21, 2015
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

An active material layer for an electrode of a lithium ion battery has a first active material comprising silicon-based particles, a second active material comprising graphite and conduits between the first active material and the second active material, the conduits being a conductive material and providing area for expansion of the first active material due to lithiation while maintaining contact between the first active material and the second active material.

First claim

What is claimed is:

1. An active material layer for an electrode of a lithium ion battery comprising:
a first active material comprising silicon-based particles;
a second active material comprising graphite; and
conduits each in physical contact at one end with the first active material and at an opposite end with the second active material, the conduits being conductive and of a material different from the first active material and the second active material, the first active material separated from the second active material by a length of a conduit during delithiation, the length of the conduit providing area for expansion of the first active material parallel to the length of the conduit and toward the second active material during lithiation while maintaining electrical contact between the first active material and the second active material.

2. The active material layer of claim 1 , wherein the conduits are carbon nanotubes.

3. The active material layer of claim 2 , wherein the carbon nanotubes are grown on the first active material and in contact with the second active material.

4. The active material layer of claim 2 , wherein the carbon nanotubes are grown on the second active material and in contact with the first active material.

5. The active material layer of claim 2 , wherein each carbon nanotube has a first diameter and each silicon-based particle has a second diameter, the first diameter being larger than the second diameter.

6. The active material layer of claim 5 , wherein the first diameter is fifty nanometers or greater.

7. The active material layer of claim 2 , wherein the carbon nanotubes have a length of up to thirty microns.

8. The active material layer of claim 1 , wherein the conduits are conductive hollow metal wires of a material that is unreactive with lithium.

9. The active material layer of claim 8 , wherein the conductive hollow metal wires are inserted into the first active material and are in contact with the second active material.

10. The active material layer of claim 8 , wherein the conductive hollow metal wires are inserted into the second active material and are in contact with the first active material.

11. The active material layer of claim 8 , wherein the conductive hollow metal wires have a first diameter and the silicon-based particles have a second diameter, the first diameter being larger than the second diameter.

12. The active material layer of claim 11 , wherein the first diameter is fifty nanometers or greater.

13. An anode of a lithium ion battery comprising:
a current collector;
a separator; and
the active material layer of claim 1 .

14. The active material layer of claim 1 , wherein the first active material further comprises one or more of tin and germanium.

Assignees

• Nissan North America Inc

Inventors

• Dale Nilesh
• Hao Xiaoguang

Classifications

• H01M4/583

  Carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/366

  as layered products · CPC title

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/626

  Metals · CPC title