ELECTRODE INCLUDING NANOSTRUCTURES FOR RECHARGEABLE CELLS

• US 20120183856A1
• Filed: 03/22/2012
• Published: 07/19/2012
• Est. Priority Date: 05/07/2009
• Status: Active Grant

• Current Assignee: Amprius Technologies Incorporated (Amprius, Inc.)
• Original Assignee: Amprius, Inc.
• Inventors: Cui, Yi, Han, Song, Platshon, Mark C.
• Granted Patent: US 10,090,512 B2
• Time in Patent Office: Days
• US Class Current: 429/223
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 2004/022 Electrodes made of one single microscopic fiber
• CPC Class Codes: H01M 4/134 Electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/1395 of electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/366 as layered products
• CPC Class Codes: H01M 4/66 Selection of materials
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 4/663 containing carbon or carbonaceous materials as conductive part, e.g. graphite, carbon fibres
• CPC Class Codes: H01M 4/75 Wires, rods or strips
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

A lithium ion battery electrode includes silicon nanowires used for insertion of lithium ions and including a conductivity enhancement, the nanowires growth-rooted to the conductive substrate.

Claims

1. A lithium ion battery electrode comprising:

a conductive substrate; and

silicon containing nanowires substrate-rooted to the conductive substrate,

the silicon containing nanowires having variable cross-sectional dimensions along the length of the silicon containing nanowires and having tapered profiles with wider ends and narrower ends,

wherein the wider ends are substrate-rooted to the conductive substrates to provide conductive attachment and mechanical support to the silicon containing nanowires with respect to the conductive substrate.

2. The electrode of claim 1, wherein the silicon containing nanowires further comprise a silicide.

3. The electrode of claim 1, wherein the silicon containing nanowires further comprise a carbide.

4. The electrode of claim 1, wherein the silicon containing nanowires each comprise a silicide core and a silicon shell.

5. The electrode of claim 1, wherein the conductive substrate comprises nickel.

6. The electrode of claim 1, wherein the conductive substrate is provided in the form of a structure selected from the group consisting of a mesh, a perforated sheet, a foam, and a felt.

7. The electrode of claim 1, the silicon containing nanowires comprise substrate-rooted cores and a layer of an electrochemically active material coating the substrate-rooted cores.

8. The electrode of claim 7, wherein the electrochemically active material comprises a material selected from the group of consisting silicon, tin, and germanium.

9. The electrode of claim 8, wherein the substrate-rooted cores comprise a silicide, and wherein the electrochemically active material consists essentially of silicon.

10. The electrode of claim 1, further comprising a shell coating the silicon containing nanowires.

11. The electrode of claim 10, wherein the shell comprising a carbon-containing material.

12. The electrode of claim 1, wherein the silicon containing nanowires each contains a narrow neck located between a substrate-rooted end and a free end of the silicon containing nanowires.

13. The electrode of claim 1, wherein the silicon containing nanowires have an average aspect ratio of at least about ten.

14. The electrode of claim 1, wherein the silicon containing nanowires have an average cross-sectional dimension of between about 1 nanometer and 10 microns on average.

15. The electrode of claim 1, wherein the silicon containing nanowires form a layer over the conductive substrate, the layer having porosity of less than about 75 percent.

16. The electrode of claim 1, wherein the silicon containing nanowires have an average length of at least about 100 micrometers.

17. The electrode of claim 1, wherein the silicon containing nanowires consist essentially of silicon.

18. The electrode of claim 1, wherein the average cross-sectional dimension of the wider ends is below the silicon fracture.

19. The electrode of claim 1, wherein the silicon containing nanowires are growth-rooted to the substrate.

20. A lithium ion battery comprising:

a negative electrode comprising a conductive substrate and silicon containing nanowires substrate-rooted to the conductive substrate,

the silicon containing nanowires having variable cross-sectional dimensions along the length of the silicon containing nanowires and having tapered profiles with wider ends and narrower ends,

wherein the wider ends are substrate-rooted to the conductive substrates to provide conductive attachment and mechanical support to the silicon containing nanowires with respect to the conductive substrate.