Lithium-iron-manganese-based composite oxide and lithium-ion secondary battery using same

Patent metadata

Field	Value
Publication number	US-2018069236-A1
Application number	US-201615551853-A
Country	US
Kind code	A1
Filing date	Feb 9, 2016
Priority date	Feb 20, 2015
Publication date	Mar 8, 2018
Grant date	—

Abstract

There is provided a lithium-iron-manganese-based composite oxide capable of providing a lithium-ion secondary battery which has a high capacity retention rate in charge/discharge cycles and in which the generation of a gas caused by charge/discharge cycles is suppressed. A lithium-iron-manganese-based composite oxide having a layered rock-salt structure, wherein at least a part of the surface of a lithium-iron-manganese-based composite oxide represented by the following formula is coated with an oxide of at least one metal selected from the group consisting of La, Pr, Nd, Sm and Eu:
Li x M 1 (y-p) Mn p M 2 (z-q) Fe q O (2-δ) wherein 1.05≦x≦1.32, 0.33≦y≦0.63, 0.06≦z≦0.50, 0<p≦0.63, 0.06≦q≦0.50, 0≦δ≦0.80, y≧p, and z≧q; M 1 is at least one element selected from Ti and Zr; and M 2 is at least one element selected from the group consisting of Co, Ni and Mn.

First claim

1 . A lithium-iron-manganese-based composite oxide having a layered rock-salt structure, wherein at least a part of a surface of a lithium-iron-manganese-based composite oxide represented by the following formula (1) is coated with an oxide of at least one metal selected from the group consisting of La, Pr, Nd, Sm and Eu:
Li x M 1 (y-p) Mn p M 2 (z-q) Fe q O (2-δ) wherein 1.05≦x≦1.32, 0.33≦y≦0.63, 0.06≦z≦0.50, 0<≦p≦0.63, 0.06≦q≦0.50, 0≦δ≦0.80, y≧p, and z≧q; M 1 is at least one element selected from Ti and Zr; and M 2 is at least one element selected from the group consisting of Co, Ni and Mn.

2 . The lithium-iron-manganese-based composite oxide according to claim 1 , wherein at least a part of a surface of the lithium-iron-manganese-based composite oxide is coated with a mixture of an oxide of at least one metal selected from the group consisting of La, Pr, Nd, Sm and Eu and an oxide of at least one metal selected from the group consisting of Ge, Mo, Zr, Al and V.

3 . A lithium-iron-manganese-based composite oxide having a layered rock-salt structure, wherein at least a part of a surface of a lithium-iron-manganese-based composite oxide represented by the following formula (1) is coated with a composite oxide of at least one metal selected from the group consisting of La, Pr, Nd, Sm and Eu and at least one metal selected from the group consisting of Ge, Mo, Zr, Al and V:
Li x M 1 (y-p) Mn p M 2 (z-q) Fe q O (2-δ) wherein 1.05≦x≦1.32, 0.33≦y≦0.63, 0.06≦z≦0.50, 0<≦p≦0.63, 0.06≦q≦0.50, 0≦δ≦0.80, y≧p, and z≧q; M 1 is at least one element selected from Ti and Zr; and M 2 is at least one element selected from the group consisting of Co, Ni and Mn.

4 . The A lithium-iron-manganese-based composite oxide according to claim 1 , wherein a content of comprising the oxide of at least one metal selected from the group consisting of La, Pr, Nd, Sm and Eu is 0.1% by mass or more and 15% by mass or less.

5 . The lithium-iron-manganese-based composite oxide according to claim 1 , wherein, in the formula (1), q satisfies 0.16≦q≦0.45.

6 . The lithium-iron-manganese-based composite oxide according to claim 1 , wherein, in the formula (1), δ satisfies 0.02≦δ≦0.50.

7 . A positive electrode active material for a lithium-ion secondary battery, wherein the positive electrode active material comprises the lithium-iron-manganese-based composite oxide according to claim 1 .

8 . A positive electrode for a lithium-ion secondary battery, wherein the positive electrode comprises the positive electrode active material for a lithium-ion secondary battery according to claim 7 .

9 . A lithium-ion secondary battery comprising the positive electrode for a lithium-ion secondary battery according to claim 8 and a negative electrode.

10 . The lithium-ion secondary battery according to claim 9 , wherein the negative electrode comprises SiO as a negative electrode active material.

11 . The lithium-iron-manganese-based composite oxide according to claim 2 , wherein a content of the mixture is 0.1% by mass or more and 15% by mass or less.

12 . The lithium-iron-manganese-based composite oxide according to claim 3 , wherein a content of the composite oxide of at least one metal selected from the group consisting of La, Pr, Nd, Sm and Eu and at least one metal selected from the group consisting of Ge, Mo, Zr, Al and V is 0.1% by mass or more and 15% by mass or less.

13 . The lithium-iron-manganese-based composite oxide according to claim 3 , wherein, in the formula (1), q satisfies 0.16≦q≦0.45.

14 . The lithium-iron-manganese-based composite oxide according to claim 3 , wherein, in the formula (1), δ satisfies 0.02≦δ≦0.50.

15 . A positive electrode active material for a lithium-ion secondary battery, wherein the positive electrode active material comprises the lithium-iron-manganese-based composite oxide according to claim 3 .

16 . A positive electrode for a lithium-ion secondary battery, wherein the positive electrode comprises the positive electrode active material for a lithium-ion secondary battery according to claim 15 .

17 . A lithium-ion secondary battery comprising the positive electrode for a lithium-ion secondary battery according to claim 16 and a negative electrode.

18 . The lithium-ion secondary battery according to claim 17 , wherein the negative electrode comprises SiO as a negative electrode active material.

Assignees

• Nec Corp
• Tanaka Chemical Corp

Inventors

• Yuge Ryota
• Tamura Noriyuki
• Hattori Sadanori
• Tabuchi Mitsuharu
• Kuratani Kentaro
• Doumae Kyousuke
• Shibuya Hideka

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• C01P2004/03

  obtained by SEM · CPC title

• H01M4/483

  for non-aqueous cells (H01M4/485 takes precedence) · CPC title

• H01M10/0525

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

• C01P2004/84

  one phase coated with the other · CPC title