Cathode active material for lithium battery, lithium battery, and method for producing cathode active material for lithium battery

Patent metadata

Field	Value
Publication number	US-9614224-B2
Application number	US-201514817956-A
Country	US
Kind code	B2
Filing date	Aug 4, 2015
Priority date	Aug 8, 2014
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

The main object of the present invention is to provide a cathode active material for a lithium battery capable of inhibiting resistance from increasing with time. The present invention attains the object by providing a cathode active material for a lithium battery comprising: a cathode active material containing an Mn element and being an oxide; and a coating portion formed on a surface of the cathode active material, characterized in that the coating portion contains a Li element, a P element, an O element and the Mn element derived from the cathode active material, and a ratio of the Mn element to the P element, (Mn/P) is 1 or more at an interface between the cathode active material and the coating portion.

First claim

What is claimed is:

1. A cathode active material complex for a lithium battery comprising:
a cathode active material comprising an Mn element and being an oxide; and
a coating portion formed on a surface of the cathode active material,
wherein the coating portion comprises a Li element, a P element, an O element and the Mn element derived from the cathode active material, and
a ratio of the Mn element to the P element, (Mn/P) is 1 or more at an interface between the cathode active material and the coating portion.

2. The cathode active material complex for a lithium battery according to claim 1 , wherein when a location in which a number of atoms of the P element (%) becomes maximum in a thickness direction of the coating portion is regarded as B, the Mn/P in the location B is 0.79 or more.

3. A lithium battery comprising a cathode active material layer, an anode active material layer, and a solid electrolyte layer formed between the cathode active material layer and the anode active material layer,
wherein the cathode active material layer comprises the cathode active material complex for a lithium battery according to claim 1 , and
at least one of the cathode active material layer and the solid electrolyte layer comprises a sulfide solid electrolyte material.

4. A lithium battery comprising a cathode active material layer, an anode active material layer, and a solid electrolyte layer formed between the cathode active material layer and the anode active material layer,
wherein the cathode active material layer comprises the cathode active material complex for a lithium battery according to claim 2 , and
at least one of the cathode active material layer and the solid electrolyte layer comprises a sulfide solid electrolyte material.

5. A method for producing a cathode active material complex for a lithium battery, the cathode active material complex for a lithium battery comprising a cathode active material comprising an Mn element and being an oxide, and a coating portion,
the method comprising a step of forming the coating portion on a surface of the cathode active material by using a sputtering method,
wherein the coating portion comprises a Li element, a P element, an O element and the Mn element derived from the cathode active material, and
a ratio of the Mn element to the P element, (Mn/P) is 1 or more at an interface between the cathode active material and the coating portion.

6. The method for producing a cathode active material complex for a lithium battery according to claim 5 , wherein when a location in which a number of atoms of the P element (%) becomes maximum in a thickness direction of the coating portion is regarded as B, the Mn/P in the location B is 0.79 or more.

7. The method for producing a cathode active material complex for a lithium battery according to claim 1 , wherein the ratio of the Mn element to the P element, (Mn/P) is 2 or more and 10 or less.

8. The method for producing a cathode active material complex for a lithium battery according to claim 1 , wherein the ratio of the Mn element to the P element, (Mn/P) is 3 or more and 10 or less.

9. The method for producing a cathode active material complex for a lithium battery according to claim 1 , wherein the cathode active material is a spinel type active material.

Assignees

• Toyota Motor Co Ltd

Inventors

• Kawakami Masatsugu
• Ohtomo Takamasa
• Kato Yuki
• Yamasaki Hisatsugu

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

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M2300/008

  Halides · CPC title

• H01M10/0525

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

• H01M10/0562

  Solid materials · CPC title