Electricity storage device

• US 8,614,019 B2
• Filed: 05/14/2009
• Issued: 12/24/2013
• Est. Priority Date: 11/16/2006
• Status: Expired due to Fees

• Current Assignee: Solignite Holding Pte. Ltd.
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Hojo, Nobuhiko, Ohtsuka, Yu, Watanabe, Shoichiro, Honda, Kazuyoshi
• Primary Examiner(s): Conley, Helen O
• Application Number:
  US12/466,112
• Publication Number:
  US 20090246631A1
• Time in Patent Office: 1,685 Days
• Field of Search: 429/231.95, 429/218.1
• US Class Current: 429/231.95
• 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 11/26 characterised by their structure, e.g. multi-layered, porosity or surface features
• CPC Class Codes: H01G 11/28 arranged or disposed on a current collector; Layers or phases between electrodes and current collectors, e.g. adhesives
• CPC Class Codes: H01G 11/32 Carbon-based
• CPC Class Codes: H01G 11/50 specially adapted for lithium-ion capacitors, e.g. for lithium-doping or for intercalation
• 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 2010/4292 Aspects relating to capacity ratio of electrodes/electrolyte or anode/cathode
• 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 4/38 of elements or alloys
• CPC Class Codes: H01M 4/382 Lithium H01M4/405 takes precedence
• 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 4/483 for non-aqueous cells H01M4/485 takes precedence
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: H01M 4/64 Carriers or collectors
• CPC Class Codes: H01M 4/70 characterised by shape or form
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/13 : Energy storage using capacitors
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries

Abstract

Disclosed is an electricity storage device which can be charged/discharged at high rate and have high output, high capacity and excellent repeating charge/discharge characteristics, although it uses a non-carbon material as a negative electrode active material. Specifically disclosed is an electricity storage device comprising: a positive electrode collector; a positive electrode disposed on the positive electrode collector and including a positive electrode active material which can reversibly absorb/desorb at least anions; a negative electrode collector; and a negative electrode disposed on the negative electrode collector and including a negative electrode active material which can substantially absorb/desorb lithium ions reversibly. The negative electrode active material is composed of at least one substance selected from the group consisting of silicon, a silicon-containing alloy, a silicon compound, tin, a tin-containing alloy, and a tin compound; and the negative electrode is formed as a thin film having a thickness of 10 μm or less.

Claims

1. An electricity storage device comprising:

a positive electrode current collector;

a positive electrode disposed on said positive electrode current collector, including a positive electrode active material capable of reversibly absorbing and desorbing at least anions;

a negative electrode current collector; and

a negative electrode disposed on said negative electrode current collector, comprising a negative electrode active material substantially capable of reversibly absorbing and desorbing lithium ions;

wherein;

said negative electrode active material is at least one selected from the group consisting of silicon, a silicon-containing alloy, a silicon compound, tin, a tin-containing alloy, and a tin compound;

lithium in an amount corresponding to an irreversible capacity of said negative electrode active material and corresponding to 20 to 95% of reversible capacity of said negative electrode active material is absorbed in said negative electrode, when said electricity storage device is in a completely discharged state; and

said negative electrode is a thin film having a thickness of 10 μ

m or less.

2. The electricity storage device in accordance with claim 1, wherein the capacity of said negative electrode per unit area is 0.2 to 2.0 mAh/cm².

3. The electricity storage device in accordance with claim 1, wherein the thickness of said positive electrode is 5 or more times the thickness of said negative electrode.

4. The electricity storage device in accordance with claim 1, wherein the specific surface area of said negative electrode is 5 or larger, said specific surface area being a ratio of a surface area within the measurement range using a laser microscope to an apparent area within the measurement range, said apparent area being an area when the measurement range is assumed to be a flat surface.

5. The electricity storage device in accordance with claim 1, wherein the specific surface area of said negative electrode current collector is 5 or larger, said specific surface area being a ratio of a surface area within the measurement range using a laser microscope to an apparent area within the measurement range, said apparent area being an area when the measurement range is assumed to be a flat surface.

6. The electricity storage device in accordance with claim 1, wherein the surface roughness value Ra of said negative electrode current collector is equal to or greater than the thickness of said negative electrode.

7. The electricity storage device in accordance with claim 1, wherein absorption of lithium into said negative electrode active material is mechanically performed.

8. The electricity storage device in accordance with claim 1, wherein said negative electrode active material is silicon.

9. The electricity storage device in accordance with claim 1, wherein said negative electrode active material is a silicon nitride or a silicon oxynitride.

10. The electricity storage device in accordance with claim 1, wherein said silicon compound is a silicon oxide represented by a formula:

SiOx (0≦

x≦

2).

11. The electricity storage device in accordance with claim 1, wherein said positive electrode active material is an activated carbon.

12. The electricity storage device in accordance with claim 1, wherein said positive electrode active material is an organic compound capable of being oxidized and reduced.

13. The electricity storage device in accordance with claim 12, wherein said organic compound has a radical in the molecule thereof.

14. The electricity storage device in accordance with claim 12, wherein said organic compound has a π

-conjugated electron cloud in the molecule thereof.

15. The electricity storage device in accordance with claim 1, wherein said negative electrode current collector has an electrolyte retention portion, the volume of said electrolyte retention portion not being less than 30% of the volume occupied by said negative electrode current collector.

16. The electricity storage device in accordance with claim 1, wherein said negative electrode current collector has an electrolyte retention portion, the volume of said electrolyte retention portion not being less than 50% the volume occupied by said negative electrode current collector.

17. The electricity storage device in accordance with claim 1, wherein said negative electrode current collector is a microporous film having a plurality of through-holes that penetrate in the thickness direction thereof.

18. The electricity storage device in accordance with claim 1, wherein said negative electrode current collector:

does not have through-holes that penetrate in the thickness direction thereof; and

has a plurality of projections on the surface thereof, with the cross-section of said projection in the thickness direction thereof shaped as a trapezoid or a pseudo-trapezoid.

19. The electricity storage device in accordance with claim 18, wherein the height of said projection is 2 or more times the thickness of said negative electrode.

20. The electricity storage device in accordance with claim 18, wherein a cover layer including a negative electrode active material is formed on at least a part of the tip portion of said projection.

21. The electricity storage device in accordance with claim 1, wherein the electricity storage device is configured for use in a laptop personal computer.

22. The electricity storage device in accordance with claim 1, wherein the electricity storage device is configured for use in a hybrid car.

23. The electricity storage device in accordance with claim 1, wherein the electricity storage device is configured for use in a cellular phone.