Lithium-manganese composite oxide, and method for producing same, and positive electrode material, positive electrode and lithium ion secondary battery using same

Patent metadata

Field	Value
Publication number	US-11552295-B2
Application number	US-202117167141-A
Country	US
Kind code	B2
Filing date	Feb 4, 2021
Priority date	Jan 31, 2017
Publication date	Jan 10, 2023
Grant date	Jan 10, 2023

Abstract

A lithium-manganese composite oxide containing a lithium-iron-manganese composite oxide represented by the composition formula. Li 1+x−w (Fe y Ni z Mn 1−y−z ) 1−x O 2−δ , where 0<x<⅓, 0≤w<0.8, 0<y<1, 0<z<0.5, y+z<1, and 0≤δ<0.5, in which at least in a state of charge of a lithium ion battery using the lithium-manganese composite oxide as a positive-electrode active material, at least some of iron atoms are pentavalent.

First claim

What is claimed is:

1. A method for producing a lithium-manganese composite oxide by a wet chemical process using a coprecipitation-baking method, said method comprising:
coprecipitating by adding an aqueous solution containing a divalent Mn salt in combination with a trivalent or higher-valent Mn salt as a Mn source to an alkaline solution to form a precipitate;
subjecting the formed precipitate to a bubbling treatment
mixing a lithium salt with the bubbled precipitate to form a mixture;
drying the mixture and grinding the dried mixture; and
baking the ground mixture and water-washing the baked mixture,
wherein the lithium-manganese composite oxide comprises a lithium-iron-manganese composite oxide represented by the composition formula: Li 1+x−w (Fe y Ni z Mn 1−y−z ) 1−x O 2−δ wherein 0<x<⅓, 0≤w<0.8, 0<y<1, 0<z<0.5, y+z<1, and 0≤δ<0.5,
wherein at least in a state of charge of a lithium ion battery comprising the lithium-manganese composite oxide as a positive-electrode active material, at least some of iron atoms are pentavalent.

2. The method for producing a lithium-manganese composite oxide according to claim 1 , wherein at least some of iron atoms are pentavalent in states of charge and discharge of the lithium ion battery.

3. The method for producing a lithium-manganese composite oxide according to claim 1 , wherein the lithium-iron-manganese composite oxide represented by the composition formula satisfies 0<w<0.8.

4. The method for producing a lithium-manganese composite oxide according to claim 1 , wherein, in the lithium-iron-manganese composite oxide represented by the composition formula, nickel is trivalent or lower-valent and manganese is tetravalent or lower-valent.

5. The method for producing a lithium-manganese composite oxide according to claim 1 , comprising detaching Li from a product obtained after the water-washing, by reacting the product with an oxidant.

6. The method for producing a lithium-manganese composite oxide according to claim 2 , wherein the lithium-iron-manganese composite oxide represented by the composition formula satisfies 0<w<0.8.

7. The method for producing a lithium-manganese composite oxide according to claim 2 , wherein, in the lithium-iron-manganese composite oxide represented by the composition formula, nickel is trivalent or lower-valent and manganese is tetravalent or lower-valent.

8. The method for producing a lithium-manganese composite oxide according to claim 1 , further comprising detaching Li from a product obtained after the water-washing, by reacting the product with bromine as an oxidant.

Assignees

• Nec Corp

Inventors

• Yuge Ryota
• Tabuchi Mitsuharu
• Doumae Kyousuke
• Shibuya Hideka

Classifications

• C01P2002/32

  spinel-type (AB2O4) · 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

• 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

• Y02E60/10

  Energy storage using batteries · CPC title