Electricity storage device

• US 9,590,249 B2
• Filed: 01/10/2011
• Issued: 03/07/2017
• Est. Priority Date: 01/15/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Moriwaka, Tamae, Takahashi, Tatsuya
• Primary Examiner(s): Ridley, Basia
• Assistant Examiner(s): ERWIN, JAMES M
• Application Number:
  US12/987,331
• Publication Number:
  US 20110177396A1
• Time in Patent Office: 2,248 Days
• Field of Search: 429/231.95, 429/304
• US Class Current: 1/1
• 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 10/054 Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium
• CPC Class Codes: H01M 10/0565 Polymeric materials, e.g. gel-type or solid-type
• CPC Class Codes: H01M 2300/0085 Immobilising or gelification of electrolyte
• CPC Class Codes: H01M 4/02 Electrodes composed of, or comprising, active material
• CPC Class Codes: H01M 4/131 Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
• 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 4/136 Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
• CPC Class Codes: H01M 4/362 Composites
• 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 4/405 Alloys based on lithium
• 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: Y02E 60/10 Energy storage using batteries

Abstract

An object is to improve characteristics of a power storage device. The present invention relates to an electricity storage device comprising a current collector and a negative electrode-active material layer formed over the current collector. The negative electrode-active material layer includes a negative electrode comprising a first negative electrode layer in contact with the current collector; a second negative electrode layer in contact with the first negative electrode layer, having a smaller capacitance than the first negative electrode layer and containing one material selected from a nitride of lithium and a transition metal represented by Li_aM_bN_z (M is a transition metal, 0.1≦a≦2.8, 0.2≦b≦1 and 0.6≦z≦1.4), a silicon material, and lithium titanate; a positive electrode that is paired with the negative electrode; and a solid electrolyte interposed between the positive electrode and the negative electrode.

Claims

1. An electricity storage device comprising:

a current collector in a plate-like form; and

a negative electrode-active material layer formed on the current collector, the negative electrode-active material layer having a laminate structure comprising;

a first negative electrode layer over the current collector, the first negative electrode layer comprising a carbon material or a composite material containing carbon; and

a second negative electrode layer over the first negative electrode layer, the second negative electrode layer containing a nitride of lithium and a transition metal represented by Li_aM_bN_z, where M represents the transition metal, a is 0.1 or more and 2.8 or less, b is 0.2 or more and 1.0 or less, and z is 0.6 or more and 1.4 or less,

wherein the current collector, the first negative electrode layer and the second negative electrode layer are discretely laminated on one another, and

wherein the first negative electrode layer is interposed between the current collector and the second negative electrode layer.

2. An electricity storage device according to claim 1, wherein the second negative electrode layer has a smaller capacitance than the first negative electrode layer.

3. An electricity storage device according to claim 1, wherein the second negative electrode layer is made of a material having a smaller volume change than graphite during an insertion-elimination reaction of ions.

10. An electricity storage device according to claim 1, further comprising:

a positive electrode; and

a solid electrolyte interposed between the positive electrode and the negative electrode-active material layer,

wherein the solid electrolyte is a gel electrolyte or a polymer electrolyte.

11. An electricity storage device according to claim 1, further comprising:

a positive electrode; and

a solid electrolyte interposed between the positive electrode and the negative electrode-active material layer,

wherein the solid electrolyte is in direct contact with the negative electrode-active material layer.

12. An electricity storage device according to claim 1, further comprising a positive electrode and a dry polymer electrolyte,

wherein the negative electrode-active material layer is between the current collector and the dry polymer electrolyte,

wherein the second negative electrode layer is in direct contact with the dry polymer electrolyte, and

wherein the dry polymer electrolyte is interposed between the negative electrode-active material layer and the positive electrode.

15. An electricity storage device according to claim 1, wherein the second negative electrode layer comprises a layer of the nitride of lithium and a transition metal represented by Li_aM_bN_z and a layer of a silicon material.

16. An electricity storage device according to claim 1, wherein the second negative electrode layer comprises a layer of the nitride of lithium and a transition metal represented by Li_aM_bN_z and a layer of a lithium titanate.

17. An electricity storage device according to claim 1, wherein the second negative electrode layer comprises a layer of the nitride of lithium and a transition metal represented by Li_aM_bN_z, a layer of a silicon material, and a layer of a lithium titanate.

18. The electricity storage device according to claim 1,

wherein an active material of the first negative electrode layer is only the carbon material or the composite material containing carbon, and

wherein an active material of the second negative electrode layer is only the nitride of lithium and the transition metal represented by Li_aM_bN_z.

19. The electricity storage device according to claim 1, wherein the first negative electrode layer has been formed on the current collector as a first plate in a first step and the second negative electrode layer has been formed on the first negative electrode layer as a second plate in a second step distinct from the first step.

20. The electricity storage device according to claim 1, wherein the first negative electrode layer has been formed by applying pressure so as to form a first plate in a first step and the second negative electrode layer has been formed by applying pressure so as to form a second plate in a second step distinct from the first step.

4. An electricity storage device comprising:

a current collector in a plate-like form; and

a negative electrode-active material layer formed on and in contact with the current collector, the negative electrode-active material layer having a laminate structure comprising;

a first negative electrode layer comprising graphite; and

a second negative electrode layer over the first negative electrode layer, the second negative electrode layer comprising a nitride of lithium and a transition metal represented by Li_aM_bN_z, where M represents the transition metal, a is 0.1 or more and 2.8 or less, b is 0.2 or more and 1.0 or less, and z is 0.6 or more and 1.4 or less,

wherein the current collector, the first negative electrode layer and the second negative electrode layer are discretely laminated on one another, and

wherein the first negative electrode layer is interposed between the current collector and the second negative electrode layer.

5. An electricity storage device according to claim 4,

wherein the second negative electrode layer has a smaller capacitance than the first negative electrode layer.

6. An electricity storage device according to claim 4, further comprising:

a positive electrode; and

a solid electrolyte interposed between the positive electrode and the negative electrode-active material layer,

wherein the solid electrolyte is a gel electrolyte or a polymer electrolyte.

7. An electricity storage device according to claim 4, further comprising:

a positive electrode; and

a solid electrolyte interposed between the positive electrode and the negative electrode-active material layer,

wherein the solid electrolyte is in direct contact with the negative electrode-active material layer.

8. An electricity storage device according to claim 4, wherein the second negative electrode layer is made of a material having a smaller volume change than graphite during an insertion-elimination reaction of ions.

13. An electricity storage device according to claim 4, further comprising a positive electrode and a dry polymer electrolyte,

wherein the negative electrode-active material layer is between the current collector and the dry polymer electrolyte,

wherein the second negative electrode layer is in direct contact with the dry polymer electrolyte, and

wherein the dry polymer electrolyte is interposed between the negative electrode-active material layer and the positive electrode.

9. An electricity storage device comprising:

a current collector in a plate-like form; and

a negative electrode-active material layer formed on and in contact with the current collector, the negative electrode-active material layer having a laminate structure comprising;

a first negative electrode layer comprising a carbon material or a composite material containing carbon; and

a second negative electrode layer over the first negative electrode layer, the second negative electrode layer comprising a nitride of lithium and a transition metal represented by Li_aM_bN_z, where M represents the transition metal, a is 0.1 or more and 2.8 or less, b is 0.2 or more and 1.0 or less, and z is 0.6 or more and 1.4 or less,

wherein the current collector, the first negative electrode layer and the second negative electrode layer are discretely laminated on one another,

wherein the first negative electrode layer is interposed between the current collector and the second negative electrode layer, and

wherein a thickness of the second negative electrode layer is less than a thickness of the first negative electrode layer.

14. An electricity storage device according to claim 9, further comprising a positive electrode and a dry polymer electrolyte,

wherein the negative electrode-active material layer is between the current collector and the dry polymer electrolyte,

wherein the second negative electrode layer is in direct contact with the dry polymer electrolyte, and

wherein the dry polymer electrolyte is interposed between the negative electrode-active material layer and the positive electrode.