Active material with expansion structure for use in lithium ion batteries

Patent metadata

Field	Value
Publication number	US-2017179467-A1
Application number	US-201514975896-A
Country	US
Kind code	A1
Filing date	Dec 21, 2015
Priority date	Dec 21, 2015
Publication date	Jun 22, 2017
Grant date	—

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 a silicon-based particles; a second active material comprising graphite; and conduits between the first active material and the second active material, the conduits being conductive 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.

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; an active material layer between the current collector and the separator, the active material layer comprising:
a first active material comprising alloying particles;
a second active material comprising a carbon material; and
conduits of a conductive material positioned between the first active material and the second active material, wherein:
during lithiation, the first active material expands along the conduits toward the second active material and during delithiation, the first active material contracts along the conduits, the conduits providing continuous contact between the first active material and the second active material during lithiation and delithiation.

14 . The anode of claim 13 , wherein the alloying particles are one or more of silicon, tin and germanium.

15 . The anode of claim 13 , wherein the conduits are carbon nanotubes.

16 . The anode of claim 15 , wherein the carbon nanotubes are grown on the first active material and in contact with the second active material.

17 . The anode of claim 15 , wherein the carbon nanotubes are grown on the second active material and in contact with the first active material.

18 . The anode of claim 15 , wherein each carbon nanotube has a first diameter and each alloying particle has a second diameter, the first diameter being larger than the second diameter.

19 . The anode of claim 18 , wherein the first diameter is fifty nanometers or greater.

20 . The anode of claim 15 , wherein the carbon nanotubes have a length of up to thirty microns.

Assignees

• Nissan North America Inc

Inventors

• Dale Nilesh
• Hao Xiaoguang

Classifications

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title

• H01M10/0525

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

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/386

  Silicon or alloys based on silicon · CPC title

• H01M4/133 Primary

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title