Positive electrode for lithium ion secondary battery and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-11018335-B2
Application number	US-201815955069-A
Country	US
Kind code	B2
Filing date	Apr 17, 2018
Priority date	Apr 28, 2017
Publication date	May 25, 2021
Grant date	May 25, 2021

Abstract

A positive electrode for a lithium ion secondary battery includes a positive electrode composite material layer. The positive electrode composite material layer includes composite particles and electron conductive particles. The composite particles include positive electrode active material particles and a coating film. The coating film is formed on the surface of the positive electrode active material particles. The coating film contains a first electron conductive oxide. The electron conductive particles are dispersed in the positive electrode composite material layer. The electron conductive particles contain a second electron conductive oxide. Each of the first electron conductive oxide and the second electron conductive oxide has a perovskite structure.

First claim

What is claimed is:

1. A positive electrode for a lithium ion secondary battery comprising:
a positive electrode composite material layer,
the positive electrode composite material layer containing composite particles and electron conductive particles,
the composite particles including positive electrode active material particles and a coating film,
the coating film being formed on the surface of the positive electrode active material particles,
the coating film containing a first electron conductive oxide,
the electron conductive particles being dispersed in the positive electrode composite material layer,
the electron conductive particles containing a second electron conductive oxide,
each of the first electron conductive oxide and the second electron conductive oxide having a perovskite structure
wherein
each of the first electron conductive oxide and the second electron conductive oxide is represented by the following formula (I):
ABO 3   (I)

wherein, in formula (I),
A represents an element contained in site A of the perovskite structure,
B represents an element contained in site B of the perovskite structure,
A represents at least one element selected from the group consisting of La and Sr,
B represents Co and optionally at least one element selected from a group consisting of Ni and Mn, and
O represents oxygen; and

wherein
the first electron conductive oxide and the second electron conductive oxide have the same chemical composition.

2. The positive electrode for a lithium ion secondary battery according to claim 1 , wherein
site B contains Co and Ni.

3. The positive electrode for a lithium ion secondary battery according to claim 1 , wherein
site B contains Co and Mn.

4. The positive electrode for a lithium ion secondary battery according to claim 1 , wherein
site B contains Co, Ni and Mn.

5. A method for manufacturing a positive electrode for a lithium ion secondary battery, comprising:
preparing composite particles by forming a coating film on the surface of positive electrode active material particles;
preparing a positive electrode composite material by mixing the composite particles and electron conductive particles; and
manufacturing the positive electrode for a lithium ion secondary battery by forming a positive electrode composite material layer containing the positive electrode composite material,
the coating film containing a first electron conductive oxide,
the electron conductive particles containing a second electron conductive oxide, and
each of the first electron conductive oxide and the second electron conductive oxide having a perovskite structure
wherein
each of the first electron conductive oxide and the second electron conductive oxide is represented by the following formula (I):
ABO 3   (I)

wherein, in formula (I),
A represents an element contained in site A of the perovskite structure,
B represents an element contained in site B of the perovskite structure,
A represents at least one element selected from the group consisting of La and Sr,
B represents Co and optionally at least one element selected from a group consisting of Ni and Mn, and
O represents oxygen; and

wherein
the first electron conductive oxide and the second electron conductive oxide have the same chemical composition.

6. The method according to claim 5 , wherein
site B contains Co and Ni.

7. The method according to claim 5 , wherein
site B contains Co and Mn.

8. The method according to claim 5 , wherein
site B contains Co, Ni and Mn.

9. A positive electrode for a lithium ion secondary battery comprising:
a positive electrode composite material layer,
the positive electrode composite material layer containing composite particles and electron conductive particles,
the composite particles including positive electrode active material particles and a coating film,
the coating film being formed on the surface of the positive electrode active material particles,
the coating film containing a first electron conductive oxide,
the electron conductive particles being dispersed in the positive electrode composite material layer,
the electron conductive particles containing a second electron conductive oxide,
each of the first electron conductive oxide and the second electron conductive oxide having a perovskite structure
wherein
each of the first electron conductive oxide and the second electron conductive oxide is represented by the following formula (I):
ABO 3   (I)

wherein, in formula (I),
A represents an element contained in site A of the perovskite structure,
B represents an element contained in site B of the perovskite structure,
A represents at least one element selected from the group consisting of La and Sr,
B represents Mn and optionally at least one element selected from a group consisting of Co and Ni, and
O represents oxygen; and

wherein
the first electron conductive oxide and the second electron conductive oxide have the same chemical composition.

10. The positive electrode for a lithium ion secondary battery according to claim 9 , wherein
site B contains Mn and Ni.

Assignees

• Toyota Motor Co Ltd
• Sumitomo Metal Mining Co

Inventors

• Horikawa Daisuke
• Sugiura Ryuta
• Kanada Satoshi
• Hayashi Tetsutaro
• Aida Taira

Classifications

• C01P2002/20

  Two-dimensional structures · CPC title

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title

• H01M4/624

  Electric conductive fillers · CPC title

• C01G53/50

  of the type (MnO2)n-, e.g. Li(NixMn1-x)O2 or Li(MyNixMn1-x-y)O2 · CPC title

• H01M10/0525

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