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

Patent metadata

Field	Value
Publication number	US-2016218360-A1
Application number	US-201414913892-A
Country	US
Kind code	A1
Filing date	Aug 19, 2014
Priority date	Aug 23, 2013
Publication date	Jul 28, 2016
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 reduced. 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 (1) is coated with an inorganic material: Li x M 1 (y-p) Mn p M 2 (z-p) Fe q O (2-δ) (1) (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 inorganic material:
Li x M 1 (y-p) Mn p M 2 (z-p) Fe q O (2-δ)   (1)
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 the inorganic material is at least one selected from the group consisting of germanium oxide, tin oxide, silicon oxide, molybdenum oxide, cerium oxide, gadolinium oxide, erbium oxide, aluminum oxide, aluminum fluoride and titanium oxide.

3 . The lithium-iron-manganese-based composite oxide according to claim 1 , wherein a content of the inorganic material is 0.1% by mass or more and 15% by mass or less.

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

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

6 . 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 .

7 . 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 6 .

8 . A lithium-ion secondary battery comprising the positive electrode for a lithium-ion secondary battery according to claim 7 and a negative electrode.

9 . The lithium-ion secondary battery according to claim 8 , wherein the negative electrode comprises SiO as a negative electrode active material.

Assignees

• Nec Corp
• Tanaka Chemical Corp

Inventors

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

Classifications

• H01M4/525

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

• H01M4/366 Primary

  as layered products · CPC title

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M10/0525

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

• H01M2004/028

  Positive electrodes · CPC title