HIGH ENERGY LITHIUM ION BATTERIES WITH PARTICULAR NEGATIVE ELECTRODE COMPOSITIONS

• US 20090305131A1
• Filed: 04/24/2009
• Published: 12/10/2009
• Est. Priority Date: 04/25/2008
• Status: Active Grant

• Current Assignee: Ionblox Incorporated (Zenlabs Energy, Inc.)
• Original Assignee: Envia Systems, Inc.
• Inventors: Buckley, James P., Kumar, Sujeet
• Granted Patent: US 8,277,974 B2
• Time in Patent Office: Days
• US Class Current: 429/206
• CPC Class Codes: B22F 3/1146 After-treatment maintaining the porosity B22F3/114 takes precedence
• CPC Class Codes: C22C 1/08 Alloys with open or closed pores
• CPC Class Codes: C22C 19/00 Alloys based on nickel or cobalt
• CPC Class Codes: H01M 10/052 Li-accumulators
• 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 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 4/387 Tin or alloys based on tin
• CPC Class Codes: H01M 4/485 of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy H01M4/505, H01M4/525 take precedence
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: H01M 4/808 Foamed, spongy materials
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 428/12 All metal or with adjacent metals
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

Combinations of materials are described in which high energy density active materials for negative electrodes of lithium ion batteries. In general, metal alloy/intermetallic compositions can provide the high energy density. These materials can have moderate volume changes upon cycling in a lithium ion battery. The volume changes can be accommodated with less degradation upon cycling through the combination with highly porous electrically conductive materials, such as highly porous carbon and/or foamed current collectors. Whether or not combined with a highly porous electrically conductive material, metal alloy/intermetallic compositions with an average particle size of no more than a micron can be advantageously used in the negative electrodes to improve cycling properties.

Claims

1. A lithium ion battery comprising a positive electrode, a negative electrode, a separator between the positive electrode and the negative electrode and an electrolyte comprising lithium ions, wherein the negative electrode comprises a foamed current collector impregnated with an active material comprising a metal alloy/intermetallic material and wherein the negative electrode lacks a foil current collector or a grid current collector separate from the foamed current collector.

2. The lithium ion battery of claim 1 wherein the foamed current collector comprises carbon, nickel, titanium, aluminum, stainless steel, or a combination thereof.

3. The lithium ion battery of claim 1 wherein the metal alloy/intermetallic are in the form of particles having an average particle size of no more than 1 micron.

4. The lithium ion battery of claim 1 wherein the metal alloy/intermetallic material comprises a tin-copper alloy or an alloy of copper, tin and one or more additional metals or combination thereof.

5. The lithium ion battery of claim 1 wherein the metal alloy/intermetallic comprises a composition having a formula Si_xSn_qM_yC_z, where (q+x)>

2y+z, q>

=0, z>

=0 and M is a metal selected from manganese, molybdenum, niobium, tungsten, tantalum, iron, copper, titanium, vanadium, chromium, nickel, cobalt, zirconium, yttrium and combinations thereof having at least about 40 weight percent and about 80 atomic percent Si as an amorphous Si phase, a nanocrystalline metal silicide phase, a silicon carbide phase when z>

0, and an amorphous Sn phase when q>

0.

6. The lithium ion battery of claim 1 wherein the metal alloy/intermetallic comprises a composition having a formula Sn-E-M, where E is boron (B), carbon (C), aluminum (Al), phosphorous (P) or a combination thereof ranging from 9.8 weight percent to 49 weight percent, and M is a metal selected from silicon, magnesium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, zirconium, niobium, molybdenum, silver, indium, cerium, hafnium, tantalum, tungsten, bismuth and combinations thereof.

7. The lithium ion battery of claim 1 wherein the positive electrode comprises an electroactive material having a discharge capacity at a 10th discharge cycle of at least 240 mAh/g at room temperature at a discharge rate of C/3 when discharged from 4.6 volts to 2.0 volts.

8. The lithium ion battery of claim 1 wherein the positive electrode comprises an electroactive material having a 10^th cycle specific discharge capacity of at least 235 mAh/g at room temperature and a tap density of at least 1.8 g/mL, wherein the specific discharge capacity is determined at a discharge rate of C/3 when discharged from 4.6 volts to 2.0 volts.

9. The lithium ion battery of claim 1 wherein the negative electrode further comprises a polymer binder.

10. A lithium ion battery comprising a positive electrode, a negative electrode, a separator between the positive electrode and the negative electrode and an electrolyte comprising lithium ions, wherein the negative electrode of the lithium ion battery comprises distinct metal and/or metal alloy/intermetallic particles, and porous carbon particles having a Brunauer-Emmett-Teller (BET) surface area of at least about 250 m²/g.

11. The lithium ion battery of claim 10 wherein the porous carbon particles have a BET surface area from about 255 to about 3500 m²/g.

12. The lithium ion battery of claim 10 wherein the porous carbon particles comprise activated carbon, mesoporous carbon, or combination thereof.

13. The lithium ion battery of claim 10 wherein the metal and/or metal alloy/intermetallic particles have an average particle size of no more than 1 micron.

14. A lithium ion battery comprising a positive electrode, a negative electrode, a separator between the positive electrode and the negative electrode and an electrolyte comprising lithium ions, wherein the negative electrode comprises metal alloy/intermetallic particles and lithium titanate particles, wherein the metal alloy/intermetallic particles and the lithium titanate particles each have an average particle size of no more than 1 micron.

15. The lithium ion battery of claim 14 wherein the metal alloy/intermetallic particles and the lithium titanate particles each have an average particle size of no more than 250 nm.

16. The negative electrode of claim 14 wherein the lithium titanate comprises from about 1 weight percent to about 45 weight percent relative to the combined weight of the metal alloy/intermetallic particles and the lithium titanate.

17. A powder comprising amorphous metal alloy/intermetallic particles wherein the particles have an average particle size of no more than about 1 micron.

18. The powder of claim 17 wherein the powder comprises metal alloy/intermetallic particles and lithium titanate particles, each having an average particle size of no more than 1 micron.

19. The powder of claim 17 wherein the metal alloy/intermetallic particles have an average particle size of no more than 250 nm.

20. The powder of claim 17 wherein the metal alloy/intermetallic particles comprise a tin-copper alloy or an alloy of copper, tin and one or more additional metals or combination thereof.

21. The powder of claim 17 wherein the metal alloy/intermetallic particles comprise a composition having a formula Si_xSn_qM_yC_z, where (q+x)>

2y+z, q>

=0, z>

=0 and M is a metal selected from manganese, molybdenum, niobium, tungsten, tantalum, iron, copper, titanium, vanadium, chromium, nickel, cobalt, zirconium, yttrium and combinations thereof having at least about 40 weight percent and about 80 atomic percent Si as an amorphous Si phase, a nanocrystalline metal silicide phase, a silicon carbide phase when z>

0, and an amorphous Sn phase when q>

0.

22. The powder of claim 17 wherein the metal alloy/intermetallic particles comprise a composition having a formula Sn-E-M, where E is boron (B), carbon (C), aluminum (Al), phosphorous (P) or a combination thereof ranging from 9.8 weight percent to 49 weight percent, and M is a metal selected from silicon, magnesium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, zirconium, niobium, molybdenum, silver, indium, cerium, hafnium, tantalum, tungsten, bismuth and combinations thereof.

23. A method for forming a metal alloy/intermetallic composition having a reduced degree of crystallinity, the method comprising milling amorphous elemental powders to form the alloy/intermetallic composition.

24. The method of claim 23 wherein the metal alloy/intermetallic composition comprises tin.

25. The method of claim 23 wherein the amorphous metal powders have an average particle size of no more than about 1 micron.

26. A method for forming a submicron carbon-metal alloy/intermetallic composite, the method comprising milling a blend of metal particles and submicron carbon materials to form an alloy/intermetallic on the submicron carbon materials.

27. A collection of composite particles comprising a metal alloy/intermetallic coated onto carbon particles wherein the carbon particles have a submicron particle size and wherein the composite particles comprise at least about 65 weight percent metal alloy/intermetallic.