Solid solution lithium-containing transition metal oxide and lithium ion secondary battery

Patent metadata

Field	Value
Publication number	US-9331335-B2
Application number	US-201314375073-A
Country	US
Kind code	B2
Filing date	Jan 31, 2013
Priority date	Feb 3, 2012
Publication date	May 3, 2016
Grant date	May 3, 2016

Abstract

A solid solution lithium-containing transition metal oxide includes a compound represented by chemical formula (1): Li 1.5 [Ni a Co b Mn c [Li] d ]O 3 , where a, b, c and d satisfy relationships: 0<a≦0.75, 0≦b≦0.5, 0<c≦1.0, 0.05≦d≦0.25, and a+b+c+d=1.5. A dQ/dV curve obtained in such a manner as to differentiate an open circuit voltage curve on a discharge side obtained by charging and discharging a lithium ion secondary battery using the compound as a positive electrode active material, fulfills math formula (1): A/B≦1.0 (where A represents a dQ/dV value at peak A located in a range from 3.0 V to 3.5 V in the dQ/dV curve, and B represents a dQ/dV value at peak B located in a range from 3.5 V to 4.0 V in the dQ/dV curve).

First claim

The invention claimed is:

1. A solid solution lithium-containing transition metal oxide comprising a compound represented by chemical formula (1):
Li 1.5 [Ni a CO b Mn c [Li] d ]O 3
where a, b, c and d satisfy relationships: 0<a≦0.75, 0≦b≦0.5, 0≦c≦1.0, 0.05≦d≦0.25, and a+b+c+d=1.5,
wherein the compound is electrochemically treated such that a dQ/dV curve obtained in such a manner as to differentiate an open circuit voltage curve on a discharge side obtained by charging and discharging a lithium ion secondary battery using the compound as a positive electrode active material, fulfills equation (2):
A/B≦ 0.4

where A represents a dQ/dV value at peak A located in a range from 3.0 V to 3.5 V in the dQ/dV curve, and B represents a dQ/dV value at peak B located in a range from 3.5 V to 4.0 V in the dQ/dV curve.

2. The solid solution lithium-containing transition metal oxide according to claim 1 , wherein, in the chemical formula (1), d satisfies 0.05≦d≦0.2.

3. The solid solution lithium-containing transition metal oxide according to claim 1 , wherein, in the chemical formula (1), d satisfies 0.05≦d≦0.15.

4. A lithium ion secondary battery comprising the solid solution lithium-containing transition metal oxide according to claim 1 .

5. The solid solution lithium-containing transition metal oxide according to claim 1 , wherein, in the chemical formula (1), d satisfies 0.1≦d≦0.2.

6. A lithium ion secondary battery comprising a solid solution lithium-containing transition metal oxide comprising a compound represented by chemical formula (1):
Li 1.5 [Ni a CO b Mn c [Li] d ]O 3
where a, b, c and d satisfy relationships: 0<a≦0.75, 0≦b≦0.5, 0<c≦1.0, 0.05≦d≦0.25, and a+b+c+d=1.5,
wherein the following electrochemical pretreatment is applied:
at a first cycle, the battery is charged at a constant current at a rate of 0.1 C until a maximum voltage of the battery reached 4.45 V and then discharged at a constant current at a rate of 0.1 C until a minimum voltage of the battery reached 2.0V,
at a second cycle, the battery is charged at a constant current at a rate of 0.1 C until a maximum voltage of the battery reached 4.55 V and then discharged at a constant current at a rate of 0.1 C until a minimum voltage of the battery reached 2.0 V,
at a third cycle, the battery is charged at a constant current at a rate of 0.1 C until a maximum voltage of the battery reached 4.65 V and then discharged at a constant current at a rate of 0.1 C until a minimum voltage of the battery reached 2.0 V,
at a forth cycle, the battery is charged at a constant current/a constant voltage at a range of 0.1 C until a maximum voltage of the battery reached 4.75 V and then discharged at a constant current at a rate of 0.1 C until a minimum voltage of the battery reached 2.0 V.

7. The lithium ion secondary battery according to claim 6 , wherein a dQ/dV curve obtained in such a manner as to differentiate an open circuit voltage curve on a discharge side obtained by charging and discharging a lithium ion secondary battery using the compound as a positive electrode active material, fulfills equation (1):
A/B≦ 1.0
where A represents a dQ/dV value at peak A located in a range from 3.0 V to 3.5 V in the dQ/dV curve, and B represents a dQ/dV value at peak B located in a range from 3.5 V to 4.0 V in the dQ/dV curve.

8. The lithium ion secondary battery according to claim 7 , wherein, in the chemical formula (1), d satisfies 0.05≦d≦0.2, and
the dQ/dV curve fulfills equation (2) regarding A and B:
A/B≦ 0.6.

9. The lithium ion secondary battery according to claim 7 , wherein, in the chemical formula (1), d satisfies 0.05≦d≦0.15, and
the dQ/dV curve fulfills equation (3) regarding A and B:
A/B≦ 0.4.

Assignees

• Nissan Motor

Inventors

• Kaburagi Tomohiro
• Ito Atsushi
• Osawa Yasuhiko
• Yamamoto Shinji

Classifications

• Y02E60/122

  Cross-Sectional Technologies · mapped topic

• H01M4/505 Primary

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

• C01G53/56

  of the type (MnO3)2-, e.g. Li2(NixMn1-x)O3 or Li2(MyNixMn1-x-y)O3 · CPC title

• H01M4/525 Primary

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• C01P2002/50

  Solid solutions · CPC title