Positive electrode active material, positive electrode for electrical device, and electrical device

Patent metadata

Field	Value
Publication number	US-9646734-B2
Application number	US-201314381399-A
Country	US
Kind code	B2
Filing date	Mar 6, 2013
Priority date	Mar 7, 2012
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

[Summary] A positive electrode active material is provided to contain: a solid solution lithium-containing transition metal oxide (A) represented by Li 1.5 [Ni a Co b Mn c [Li] d ]O 3 (where a, b, c and d satisfy the relations of a+b+c+d=1.5, 0.1<d≦0.4, 1.1≦a+b+c<1.4, 0.2≦a≦0.7 and 0<b/a<1); and a lithium-containing transition metal oxide (B) represented by LiM X Mn 2−X O 4 (where M represents Cr or Al, and x satisfies the relation of 0≦x<2).

First claim

The invention claimed is:

1. A positive electrode active material comprising:
a solid solution lithium-containing transition metal oxide (A) comprising
Li 1.5 [Ni a Co b Mn c [Li] d ]O 3   (1),

wherein in (1), Li is lithium, Ni is nickel, Co is cobalt, Mn is manganese and O represents oxygen, wherein a, b, c and d satisfy the relations of 0.25<a<0.44, 0<b<0.44, 0.37<c<1.1, 0.15≦d≦0.25, a+b+c+d=1.5, 1.25≦a+b+c≦1.35, and 0<b/a<1, and the solid solution lithium-containing transition metal oxide (A) comprises a spinel structure and a spinel structure change ratio of not smaller than 0.5 and smaller than 0.9; and
a lithium-containing transition metal oxide (B) comprising
LiM x Mn 2−x O 4   (2),

wherein in (2), Li is lithium, Mn is manganese, O is oxygen, M represents Cr or Al, and x satisfies the relation of 0≦x<2, and
wherein the solid solution lithium-containing transition metal oxide (A) and the lithium-containing transition metal oxide (B) satisfy the following relational expression (3)
0.50≦M B /(M A +M B )<1.00  (3),

wherein in the expression (3), M A represents the mass of the solid solution lithium-containing transition metal oxide (A) and M B represents the mass of the lithium-containing transition metal oxide (B).

2. A positive electrode active material as claimed in claim 1 , wherein the solid solution lithium-containing transition metal oxide (A) and the lithium-containing transition metal oxide (B) satisfy the following relational expression (4)
0.75≦M B /(M A +M B )<1.00  (4),

wherein in the expression (4), M A represents the mass of the solid solution lithium-containing transition metal oxide (A) and M B represents the mass of the lithium-containing transition metal oxide (B).

3. A positive electrode active material as claimed in claim 1 , wherein x satisfies the relation of 0<x<0.5.

4. A positive electrode active material as claimed in claim 1 , wherein:
the solid solution lithium-containing transition metal oxide (A) has a BET specific surface area of not smaller than 0.8 m 2 /g and not larger than 10.0 m 2 /g; and
the solid solution lithium-containing transition metal oxide (A) has a 50% passing particle diameter of not more than 20 μm.

5. A positive electrode active material as claimed in claim 4 , wherein:
the solid solution lithium-containing transition metal oxide (A) has a primary particle diameter of not smaller than 30 nm and not larger than 200 nm.

6. A positive electrode active material as claimed in claim 1 , wherein:
the lithium-containing transition metal oxide (B) has a BET specific surface area of not smaller than 0.2 m 2 /g and not larger than 3.0 m 2 /g; and
the lithium-containing transition metal oxide (B) has a 50% passing particle diameter of not more than 20 μm.

7. A positive electrode for an electrical device, comprising:
a positive electrode active material as claimed in claim 1 .

8. An electrical device comprising:
a positive electrode for an electrical device, as claimed in claim 7 .

9. An electrical device as claimed in claim 8 , wherein the electrical device is a lithium ion secondary battery.

10. A positive electrode active material as claimed in claim 1 , wherein the solid solution lithium-containing transition metal oxide (A) further comprises a first layered structure portion and a second layered structure portion changeable into the spinel structure.

11. A positive electrode active material as claimed in claim 10 , wherein the second layered structure portion changes into the spinel structure within an electric potential range of not less than 4.3V and not more than 4.8V.

Assignees

• Nissan Motor

Inventors

• Ito Atsushi
• Yamamoto Shinji

Classifications

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title

• C01P2006/12

  Surface area · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title