Hybrid Energy Storage Device Charging

• US 20130169238A1
• Filed: 02/27/2013
• Published: 07/04/2013
• Est. Priority Date: 02/25/2009
• Status: Active Grant

• Current Assignee: CF Traverse LLC (SoftBank Group Corp.)
• Original Assignee: CF Traverse LLC (SoftBank Group Corp.)
• Inventors: Rojeski, Ronald A.
• Granted Patent: US 9,941,709 B2
• Time in Patent Office: Days
• US Class Current: 320/137
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• 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 10/446 Initial charging measures
• CPC Class Codes: H01M 4/0438 by electrochemical processing electroless electrochemical plating C23C18/54
• 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 4/1393 of electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
• 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 4/38 of elements or alloys
• CPC Class Codes: H01M 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A novel hybrid lithium-ion anode material based on coaxially coated Si shells on vertically aligned carbon nanofiber (CNF) arrays. The unique cup-stacking graphitic microstructure makes the bare vertically aligned CNF array an effective Li⁺ intercalation medium. Highly reversible Li⁺ intercalation and extraction were observed at high power rates. More importantly, the highly conductive and mechanically stable CNF core optionally supports a coaxially coated amorphous Si shell which has much higher theoretical specific capacity by forming fully lithiated alloy. Addition of surface effect dominant sites in close proximity to the intercalation medium results in a hybrid device that includes advantages of both batteries and capacitors.

Claims

1. A method of charging a charge storage device, the method comprising

establishing a potential between a cathode and an anode of the charge storage device, the charge storage device including an electrolyte;

receiving a first charge carrier of the electrolyte at a surface effect dominant site of the anode;

transferring an electron of the anode to the first charge carrier;

receiving a second charge carrier of the electrolyte at an intercalation material of the anode; and

transferring an electron from the intercalation material to the second charge carrier.

2. The method of claim 1, wherein the first charge carrier includes lithium.

3. The method of claim 1, wherein the potential results in an electrostatic potential difference between the surface effect dominant site and the intercalation material of less than 2.4V.

4. The method of claim 1, wherein the surface effect dominant site is configured to catalyze intercalation of the first charge carrier into the intercalation material.

5. The method of claim 1, wherein the surface effect dominant site is disposed on a nanoparticle including titanium.

6. The method of claim 1, wherein the surface effect dominant site is one of a layer of surface effect dominant sites in a layer on a surface of the intercalation material.

7. The method of claim 1, wherein the steps of receiving the first charge carrier and receiving the second charge carrier occur contemporaneously.

8. The method of claim 1, wherein the surface effect dominant site is one of a plurality of surface effect dominant sites distributed within a binder.

9. The method of claim 8, wherein a concentration of the surface effect dominant sites adjacent to a surface of the intercalation material is greater than a concentration of the surface effect dominant sites elsewhere within the binder.

10. The method of claim 8, wherein the step of receiving the second charge carrier causes an increase in a volume of the intercalation material and a reduction in a surface density of the surface effect dominant sites on the intercalation material.

11. The method of claim 10, wherein the reduction in surface density results in an increase in a rate of intercalation of charge carriers within the intercalation material.

12. A method of charging a charge storage device, the method comprising:

establishing a potential gradient at an anode of the charge storage device, the anode including an electrolyte, a plurality of nanoparticles having surface effect dominant sites, an intercalation material and a substrate;

receiving a first charge carrier of the electrolyte at one of the surface effect dominant sites;

transferring an electron to the first charge carrier from the one of the surface effect dominant sites;

receiving a second charge carrier at the intercalation material of the anode; and

transferring an electron from the intercalation material to the second charge carrier.

13. The method of claim 12, wherein the first charge carrier includes lithium.

14. The method of claim 12, wherein the second charge carrier is an oxide of the first charge carrier.

15. The method of claim 12, wherein the surface effect dominant sites are configured to catalyze intercalation of the first charge carrier into the intercalation material.

16. The method of claim 12, wherein intercalation of the first charge carrier into the bulk of a nanoparticle that includes the surface effect dominant sites is thermodynamically less favorable then intercalation of the first charge carrier into the intercalation material.

17. The method of claim 12, wherein the first charge carrier and the second charge carrier consist of the same chemical species.

18. The method of claim 12, wherein the intercalation material includes Ag, Al, Bi, C, Ge, Sb, Si, Sn or Zn.

19. The method of claim 12, wherein the plurality of nanoparticles are disposed on a surface of the intercalation material.

20. The method of claim 12, wherein the intercalation material is coated on a support filament.

21. The method of claim 12, wherein the intercalation material is coated on a vertically aligned carbon nanofiber.

22. The method of claim 12, wherein transferring the electron of the first charge carrier from the one of the surface effect dominant sites and transferring the electron to the second charge carrier from the intercalation material occurs at reaction potentials that are at less than 2.4V different.

23. The method of claim 12, wherein a reaction potential at which the electron is transferred from the intercalation material to the second charge carrier is sufficient to cause intercalation of the second charge carrier into the intercalation material but not sufficient to cause significant intercalation of the second charge carrier into the nanoparticles.

24. The method of claim 12, wherein receiving the second charge carrier at the intercalation material results in a decrease in the surface coverage of the nanoparticles on the intercalation material.

25. The method of claim 12, wherein receiving the second charge carrier at the intercalation material results in an increase in a rate at which charge carriers are intercalated in the intercalation material.

26. The method of claim 12, wherein the surface effect dominant sites are configured to produce an oxide of the first charge carrier and the intercalation material is configured to reduce the second charge carrier.

27. The method of claim 12, further comprising transferring an oxygen from the intercalation material to the surface effect dominant sites.

28. The method of claim 27, wherein the oxygen is received at the intercalation material as an oxide of the first charge carrier.