Lithium-alloying-material/carbon composite

• US 8,361,659 B2
• Filed: 06/20/2008
• Issued: 01/29/2013
• Est. Priority Date: 06/20/2008
• Status: Active Grant

• Current Assignee: Toyota Motor Corporation
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation)
• Inventors: Richard, Monique N.
• Primary Examiner(s): Ryan, Patrick
• Assistant Examiner(s): USYATINSKY, ALEXANDER
• Application Number:
  US12/143,195
• Publication Number:
  US 20090317720A1
• Time in Patent Office: 1,684 Days
• Field of Search: 429/213, 429/231.95, 429/224, 429/223, 429/221, 429/231.8, 252/583
• US Class Current: 429/231.8
• 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 2004/021 Physical characteristics, e.g. porosity, surface area
• CPC Class Codes: H01M 4/133 Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/134 Electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/364 as mixtures
• CPC Class Codes: H01M 4/38 of elements or alloys
• CPC Class Codes: H01M 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 4/387 Tin or alloys based on tin
• CPC Class Codes: H01M 4/40 Alloys based on alkali metals
• CPC Class Codes: H01M 4/405 Alloys based on lithium
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

An electrode material having carbon and lithium-alloying-material is provided. The carbon is in the form of a porous matrix having nanoporosity and the lithium-alloying-material is sorbed into the nanoporosity of the carbon matrix. The carbon matrix can have a volume of nanoporosity between 10 and 99%. In addition, the lithium-alloying-material can occupy between 5 to 99% of the nanoporosity. A portion of the carbon structure that is only partially filled with the lithium-alloying-material remains vacant providing room for volume expansion on alloying with lithium and allowing electrolyte egress. In some instances, the nanoporosity has nanopores and nanochannels with an average diameter between 1 nanometer and 999 nanometers. The lithium-alloying-material is sorbed into the nanoporosity using liquid transport or other mechanisms providing a material having intimate contact between the electronically conductive carbon structure and the electroactive lithium-alloying-material.

Claims

1. A material comprising:

carbon and a lithium-alloying-material;

said carbon in the form of a porous matrix having a nanoporosity, said nanoporosity having a volume; and

said lithium-alloying-material sorbed into a portion of said nanoporosity of said carbon matrix such that said lithium-alloying-material occupies more than 50% and less than 100% of said nanoporosity volume and there is free volume available within said nanoporosity volume.

2. The material of claim 1, wherein said matrix has between 10% and 99% of said nanoporosity volume.

3. The material of claim 2, wherein said lithium-alloying-material occupies more than 75% and less than 100% of said nanoporosity volume.

4. The material of claim 1, wherein said nanoporosity volume has nanopores and nanochannels with an average diameter between 1 nanometer and 999 nanometers.

5. The material of claim 4, wherein said nanopores and said nanochannels have an average diameter between 1 nanometer and 50 nanometers.

6. The material of claim 4, wherein said nanopores and said nanochannels have an average diameter between 1 nanometer and 30 nanometers.

7. The material of claim 4, wherein said nanopores and said nanochannels have an average diameter between 1 nanometer and 20 nanometers.

8. The material of claim 4, wherein said lithium-alloying-material is selected from the group consisting of tin, silicon, aluminum, germanium and alloys thereof.

9. An electrode comprising the material according to claim 1.

10. The electrode of claim 9, further comprising a binding compound, other additives and combinations thereof.

11. A battery having:

a negative electrode according to claim 9;

an electrolyte; and

a positive electrode.

12. A material comprising:

carbon and a lithium-alloying-material;

said carbon in the form of a porous matrix having nanopores and nanochannels defining a porosity, said porosity having a volume and said nanopores and said nanochannels having an average diameter between 1 nanometer and 999 nanometers; and

said lithium-alloying-material sorbed into a portion of said nanopores and said nanochannels of said carbon matrix and occupying more than 50% and less than 100% of said porosity volume such that is free volume available within said porosity volume.

13. The material of claim 12, wherein said matrix has between 10% and 99% of said porosity volume.

14. The material of claim 13, wherein said lithium-alloying-material is selected from the group consisting of tin, silicon, aluminum, germanium and alloys thereof.

15. A battery having a carbon and lithium-alloying-material electrode, the battery comprising:

a positive electrode containing lithium;

an electrolyte;

a negative electrode, said negative electrode having;

a porous carbon matrix having nanopores and nanochannels defining a nanoporosity, said nanoporosity having a volume and said nanopores and said nanochannels having an average diameter between 1 nanometer and 999 nanometers; and

a lithium-alloying-material sorbed into a portion of said nanopores and said nanochannels of said carbon matrix and occupying more than 50% and less than 100% of said nanoporosity volume such that there is free volume available within said nanoporosity volume.