ANODES FOR LITHIUM-ION DEVICES

• US 20170207451A1
• Filed: 04/05/2017
• Published: 07/20/2017
• Est. Priority Date: 07/30/2014
• Status: Active Grant

• Current Assignee: StoreDot Ltd.
• Original Assignee: StoreDot Ltd.
• Inventors: BURSHTAIN, Doron, ARONOV, Daniel, AMIR, Liron, GUCHOK, Olga, KRASOVITSKY, Leonid
• Granted Patent: US 10,199,646 B2
• Time in Patent Office: Days
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H01G 11/06 with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC]
• CPC Class Codes: H01G 11/30 characterised by their material
• CPC Class Codes: H01G 11/36 Nanostructures, e.g. nanofibres, nanotubes or fullerenes
• CPC Class Codes: H01G 11/46 Metal oxides
• CPC Class Codes: H01G 11/50 specially adapted for lithium-ion capacitors, e.g. for lithium-doping or for intercalation
• CPC Class Codes: H01G 11/56 Solid electrolytes, e.g. gels; Additives therein
• CPC Class Codes: H01G 11/86 specially adapted for electrodes carbonisation or activation of carbon for the manufacture of electrodes H01G11/34
• CPC Class Codes: H01M 10/052 Li-accumulators
• 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 2004/027 Negative electrodes
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/364 as mixtures
• CPC Class Codes: H01M 4/366 as layered products
• CPC Class Codes: H01M 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 4/58 of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

An anode material for a lithium ion device includes an active material including silicon nanoparticles and boron carbide nanoparticles. The boron carbide nanoparticles are at least one order of magnitude smaller than the silicon nanoparticles. The weight percentage of the silicon is between about 4 to 35 weight % of the total weight of the anode material and the weight percentage of the boron carbide is between about 2.5 to about 25.6% of the total weight of the anode material. The active material may include carbon at a weight percentage of between 5 to about 60 weight % of the total weight of the anode material. Additional materials, methods of making and devices are taught.

Claims

1. An anode material for a lithium ion device, comprising:

an active material comprising silicon nanoparticles and boron carbide nanoparticles, wherein the boron carbide nanoparticles are at least one order of magnitude smaller than the silicon nanoparticles,

and wherein the weight percentage of the silicon nanoparticles is between about 4 to about 35 weight % of the total weight of the anode material and the weight percentage of the boron carbide nanoparticles is between about 2.5 to about 25.6 weight % of the total weight of the anode material.

2. The anode material of claim 1, wherein each of the silicon nanoparticles is coated on at least a region of its surface by some of the boron carbide nanoparticles.

3. The anode material of claim 2, wherein at least some of silicon nanoparticles coated with the boron carbide nanoparticle are further coated with a film of at least one of:

carbon and transition metal oxide.

4. The anode material of claim 2, wherein aggregates that include a plurality of silicon nanoparticles coated with the boron carbide nanoparticle are being further coated with a film of at least one of:

carbon and transition metal oxide.

5. The anode material according to claim 1, wherein the boron carbide nanoparticles are at least partially embedded in the surface of each silicon nanoparticle.

6. The anode material of claim 1, wherein the active material further comprises carbon, not included in the boron carbide, at a weight percentage of about between 5 to about 60 weight % of the total weight of the anode material.

7. The anode material of claim 1, wherein the active material further comprises tungsten-carbide nanoparticles at a weight percentage of between about 7.45 to about 13.85 weight % of the total weight of the anode material.

8. The anode material of claim 1, further comprising:

a binder at a weight percentage of between about 0.1 to about 10 weight % of the total weight of the anode material.

9. The anode material of claim 1, further comprising:

carbon nano-tubes (CNT) at a weight percentage of between about 0.05 to about 0.5 weight % of the total weight of the anode material.

10. An active material for a producing anode for lithium ion devices, the active material, comprising:

silicon nanoparticles at a weight percentage of between 5 to about 47 weight % of the total weight of the active material; and

boron carbide nanoparticles at a weight percentage of between about 3.8 to about 32 weight % of the total weight of the active material,

wherein the boron carbide nanoparticles are at least one order of magnitude smaller than the silicon nanoparticles.

11. An active material according to claim 10, wherein each of the silicon nanoparticles is coated on at least a region of its surface by some of the boron carbide nanoparticles.

12. An active material according to claim 11, wherein at least some of silicon nanoparticles coated with the boron carbide nanoparticle are further coated with a film of at least one of:

carbon and transition metal oxide.

13. An active material according to claim 11, wherein aggregates that include a plurality of silicon nanoparticles coated with the boron carbide nanoparticle are further coated with a film of at least one of:

carbon and transition metal oxide.

14. An active material according to claim 10, wherein the boron carbide nanoparticles are at least partially embedded in the surface of each silicon nanoparticle.

15. A lithium ion device comprising:

an anode having an active material comprising silicon nanoparticles and boron carbide nanoparticles, wherein the boron carbide nanoparticles are at least one order of magnitude smaller than the silicon nanoparticles, wherein the weight percentage of the silicon nanoparticles is between about 4 to about 35 weight % of the total weight of the anode and the weight percentage of the boron carbide nanoparticles is between about 2.5 to about 25.6 weight % of the total weight of the anode;

a cathode; and

an electrolyte.

16. The lithium ion device of claim 16, wherein the silicon nanoparticles is coated on at least a region of its surface by some of the boron carbide nanoparticles.

17. The lithium ion device of claim 16, wherein at least some of silicon nanoparticles coated with the boron carbide nanoparticle are further coated with a film of at least one of:

carbon and transition metal oxide.

18. A method for making an anode material for a lithium ion device, comprising:

forming an active material comprising silicon nanoparticles coated with boron carbide nanoparticles,

wherein the boron carbide nanoparticles are at least one order of magnitude smaller than the silicon nanoparticles,

and wherein the weight percentage of the silicon nanoparticles is between about 4 to about 35 weight % of the total weight of the anode material and the weight percentage of the boron carbide nanoparticles is between about 2.5 to about 25.6 weight % of the total weight of the active material.

19. The method of claim 18, further comprising coating the silicon nanoparticles with a film of at least one of:

carbon and transition metal oxide.

20. The method of claim 18, wherein forming includes at least one of:

high energy ball milling, spattering, chemical precipitation.