POSITIVE ELECTRODE ACTIVE MATERIAL

• US 20110008233A1
• Filed: 07/02/2010
• Published: 01/13/2011
• Est. Priority Date: 07/10/2009
• Status: Abandoned Application

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: TAKAHASHI, Masahiro, MIYANAGA, Akiharu, KOEZUKA, Junichi
• Application Number:
  US12/829,410
• Publication Number:
  US 20110008233A1
• Time in Patent Office: Days
• US Class Current: 423/306
• CPC Class Codes: C01B 25/45 containing plural metal, or metal and ammonium
• 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 2004/028 Positive electrodes
• CPC Class Codes: H01M 4/045 Electrochemical coating; Electrochemical impregnation
• 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 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A highly effective positive electrode is obtained by using a material such as Na which is an inexpensive abundant resource. A positive electrode active material of sodium transition metal phosphate of olivine structure in which the sodium transition metal phosphate of olivine structure includes, a phosphorus atom that is located at the center of a tetrahedron having an oxygen atom in each vertex, a transition metal atom that is located at the center of a first octahedron having an oxygen atom in each vertex; and a sodium atom that is located at the center of a second octahedron having an oxygen atom in each vertex, and adjacent sodium atoms are arranged one-dimensionally in a <010> direction.

Claims

1. A positive electrode active material comprising sodium transition metal phosphate having an olivine structure, wherein adjacent sodium atoms in the positive electrode active material are arranged in one direction and in a <

010>

direction without being inhibited by other atoms.

2. The positive electrode active material according to claim 1, wherein the sodium transition metal phosphate is sodium iron phosphate.

3. The positive electrode active material according to claim 1, wherein the sodium transition metal phosphate is sodium nickel phosphate.

4. The positive electrode active material according to claim 1, wherein the sodium transition metal phosphate is sodium cobalt phosphate.

5. The positive electrode active material according to claim 1, wherein the sodium transition metal phosphate is sodium manganese phosphate.

6. A secondary battery comprising the positive electrode active material according to claim 1.

7. A positive electrode active material comprising sodium transition metal phosphate having an olivine structure, wherein adjacent sodium atoms in the positive electrode active material are arranged in one direction and in a b-axis direction without being inhibited by other atoms.

8. The positive electrode active material according to claim 7, wherein the sodium transition metal phosphate is sodium iron phosphate.

9. The positive electrode active material according to claim 7, wherein the sodium transition metal phosphate is sodium nickel phosphate.

10. The positive electrode active material according to claim 7, wherein the sodium transition metal phosphate is sodium cobalt phosphate.

11. The positive electrode active material according to claim 7, wherein the sodium transition metal phosphate is sodium manganese phosphate.

12. A secondary battery comprising the positive electrode active material according to claim 7.

13. A positive electrode active material comprising sodium transition metal phosphate having an olivine structure;

wherein a phosphorus atom is located at a center of a tetrahedron having an oxygen atom in each vertex,

wherein a transition metal atom is located at a center of a first octahedron having an oxygen atom in each vertex,

wherein a sodium atom is located at a center of a second octahedron having an oxygen atom in each vertex, and

wherein adjacent sodium atoms in the positive electrode active material are arranged in a <

010>

direction without being inhibited by other atoms.

14. The positive electrode active material according to claim 13, wherein the transition metal atom is an iron atom and the sodium transition metal phosphate is sodium iron phosphate.

15. The positive electrode active material according to claim 13, wherein the transition metal atom is a nickel atom and the sodium transition metal phosphate is sodium nickel phosphate.

16. The positive electrode active material according to claim 13, wherein the transition metal atom is a cobalt atom and the sodium transition metal phosphate is sodium cobalt phosphate.

17. The positive electrode active material according to claim 13, wherein the transition metal atom is a manganese atom and the sodium transition metal phosphate is sodium manganese phosphate.

18. A secondary battery comprising the positive electrode active material according to claim 13.

19. A positive electrode active material comprising sodium transition metal phosphate having an olivine structure;

wherein a phosphorus atom is located at a center of a tetrahedron having an oxygen atom in each vertex,

wherein a transition metal atom is located at a center of a first octahedron having an oxygen atom in each vertex,

wherein a sodium atom is located at a center of a second octahedron having an oxygen atom in each vertex, and

wherein adjacent sodium atoms in the positive electrode active material are arranged in a b-axis direction without being inhibited by other atoms.

20. The positive electrode active material according to claim 19, wherein the transition metal atom is an iron atom and the sodium transition metal phosphate is sodium iron phosphate.

21. The positive electrode active material according to claim 19, wherein the transition metal atom is a nickel atom and the sodium transition metal phosphate is sodium nickel phosphate.

22. The positive electrode active material according to claim 19, wherein the transition metal atom is a cobalt atom and the sodium transition metal phosphate is sodium cobalt phosphate.

23. The positive electrode active material according to claim 19, wherein the transition metal atom is a manganese atom and the sodium transition metal phosphate is sodium manganese phosphate.

24. A secondary battery comprising the positive electrode active material according to claim 19.