Anode active material and battery

Patent metadata

Field	Value
Publication number	US-9876225-B2
Application number	US-201414567263-A
Country	US
Kind code	B2
Filing date	Dec 11, 2014
Priority date	Nov 4, 2005
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

Anode active materials, anodes, and batteries are provided. In one embodiment, an anode active material includes particles consisting essentially of a material selected from the group consisting of silicon and an alloy of silicon. An average degree of circularity of the particles is 90% or less.

First claim

The invention is claimed as follows:

1. An anode active material comprising:
particles consisting essentially of silicon,
wherein an average degree of circularity of the particles is less than 70%, and an average particle diameter is 0.3 μm to 20 μm.

2. The anode active material according to claim 1 , wherein the average particle diameter is 0.3 μm to 10 μm.

3. The anode active material according to claim 1 , further comprising a carbon material.

4. The anode active material according to claim 1 , wherein the particles are monolithic particles.

5. An anode comprising:
an anode current collector; and
an anode active material layer provided on the anode current collector, the anode active material layer comprising particles consisting essentially of silicon,
wherein an average degree of circularity of the particles is less than 70%, and an average particle diameter is 0.3 μm to 20 μm.

6. The anode according to claim 5 , wherein a surface roughness Ra of the anode current collector ranges from 0.1 μm to 3.5 μm.

7. A battery comprising:
a cathode;
an anode; and
an electrolytic solution,
wherein the anode contains an anode active material comprising particles consisting essentially of silicon, and
wherein an average degree of circularity of the particles is less than 70%, and an average particle diameter is 0.3 μm to 20 μm.

8. The battery according to claim 7 , wherein a discharge capacity retention ratio of the battery increases as the average degree of circularity of the particles is lowered.

9. An electronic device including a battery as recited in claim 7 .

10. The electronic device according to claim 9 , wherein the electronic device is a mobile device.

Assignees

• Sony Corp
• Murata Manufacturing Co

Inventors

• Kawase Kenichi
• Takada Tomoo
• Yamamoto Kensuke

Classifications

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title

• H01M4/1395

  of electrodes based on metals, Si or alloys · CPC title

• H01M4/38

  of elements 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

• H01M4/386 Primary

  Silicon or alloys based on silicon · CPC title