Positive electrode active material for non-aqueous secondary battery and method of manufacturing thereof
A positive electrode active material for non-aqueous secondary battery includes core particles containing a lithium transition metal composite oxide, and a covering layer covering, that covers a surface of the core particle. The covering layer contains niobium and carbonate ions, and the carbonate ions are present at a concentration of from 0.2 weight % to 0.4 weight %. The positive electrode active material for non-aqueous secondary battery exhibits infrared absorption peaks at a wavenumber range of from 1320 cm −1 to 1370 cm −1 , and at a wavenumber range of from 1640 cm −1 to 1710 cm −1 .
1. A positive electrode active material for non-aqueous secondary battery, the positive electrode active material comprising:
core particles containing a lithium transition metal composite oxide, and
a covering layer, that covers a surface of the core particle, wherein the covering layer comprises niobium and carbonate ion and the carbonate ions are present at a concentration of from 0.2 weight % to 0.4 weight %;
and exhibits infrared absorption peaks at a wavenumber range of from 1320 cm-1 to 1370 cm −1 , and at a wavenumber range of from 1640 cm-1 to 1710 cm −1 ,
wherein the lithium transition metal complex oxide is represented by the following formula:
Li a Ni 1-x-y Co x Mn y O 2
and a, x, and y, respectively, satisfy 0.95≦a≦1.2, 0.30≦x≦0.40, 0.30≦y≦0.40, 0.60≦x+y≦0.70.
2. The positive electrode active material according to claim 1 , wherein the niobium in the covering layer is present at a concentration of from 0.05 mol % to 5.0 mol % with respect to the lithium transition metal composite oxide.
3. The positive electrode active material according to claim 2 , wherein the carbonate ion concentration in the covering layer is in a range of from 0.2 weight % to 0.3 weight %.
4. The positive electrode active material according to claim 3 , wherein the particle diameter of the core particles may be in a range of from 3 μm to 20 μm in terms of volume average particle diameter.
5. The positive electrode active material according to claim 2 , wherein the particle diameter of the core particles may be in a range of from 3 μm to 20 μm in terms of volume average particle diameter.
6. The positive electrode active material according to claim 1 , wherein the carbonate ion concentration in the covering layer is in a range of from 0.2 weight % to 0.3 weight %.
7. The positive electrode active material according to claim 6 , wherein the content of niobium in the covering layer is in a range of from 0.5 mol % to 3.0 mol % with respect to the lithium transition metal composite oxide.
8. The positive electrode active material according to claim 7 , wherein the particle diameter of the core particles may be in a range of from 3 μm to 20 μm in terms of volume average particle diameter.
9. The positive electrode active material according to claim 6 , wherein the particle diameter of the core particles may be in a range of from 3 μm to 20 μm in terms of volume average particle diameter.
10. The positive electrode active material according to claim 1 , wherein the content of niobium in the covering layer is in a range of from 0.5 mol % to 3.0 mol % with respect to the lithium transition metal composite oxide.
11. The positive electrode active material according to claim 10 , wherein the particle diameter of the core particles may be in a range of from 3 μm to 20 μm in terms of volume average particle diameter.
12. The positive electrode active material according to claim 1 , wherein the particle diameter of the core particles may be in a range of from 3 μm to 20 μm in terms of volume average particle diameter.