Positive Electrode Active Material, Positive Electrode, All-Solid-State Battery, and Method of Producing Positive Electrode Active Material

Patent metadata

Field	Value
Publication number	US-2024297298-A1
Application number	US-202418438981-A
Country	US
Kind code	A1
Filing date	Feb 12, 2024
Priority date	Mar 2, 2023
Publication date	Sep 5, 2024
Grant date	—

Abstract

A positive electrode active material comprises an active material particle and a coating film. The coating film covers at least part of a surface of the active material particle. The coating film includes a first compound or a second compound. The first compound includes a glass network forming element. The first compound does not include phosphorus. The first compound satisfies the relationship of “0.55≤C Li /C E ≤1.03”. The second compound includes phosphorus and the glass network forming element. The second compound satisfies the relationship of “0.20≤C P /C E ≤8.72”. Each of C Li , C E , and C P represents an element concentration measured by XPS. C Li represents an element concentration of lithium. C E represents an element concentration of the glass network forming element. C P represents an element concentration of phosphorus.

First claim

What is claimed is:

1 . A positive electrode active material comprising:
an active material particle; and a coating film, wherein the coating film covers at least part of a surface of the active material particle, the coating film includes a first compound or a second compound, the first compound includes a glass network forming element, the first compound does not include phosphorus, the first compound satisfies a relationship of an expression (1):

0.55
≤

C
Li

/

C
E

≤

1
.
0

⁢
3

(
1
)

the second compound includes phosphorus and the glass network forming element,
the second compound satisfies a relationship of an expression (2):

0.2
≤

C
P

/

C
E

≤

8
.
7

⁢
2

(
2
)

in the above expression (1) and the above expression (2),
each of C Li , C E , and C P represents an element concentration measured by X-ray photoelectron spectroscopy,
C Li represents an element concentration of lithium,
C E represents an element concentration of the glass network forming element, and
C P represents an element concentration of phosphorus.

2 . The positive electrode active material according to claim 1 , wherein the glass network forming element is boron.

3 . The positive electrode active material according to claim 1 , wherein the second compound further satisfies a relationship of an expression (3):

0.49
≤

C
Li

/

(

C
P

+

C
E

)

≤

2
⁢

.38
.

(
3
)

4 . The positive electrode active material according to claim 1 , wherein the positive electrode active material has a covering rate of 89% or more, and the covering rate is measured by X-ray photoelectron spectroscopy.

5 . A positive electrode comprising the positive electrode active material according to claim 1 and a sulfide solid electrolyte.

6 . An all-solid-state battery comprising the positive electrode according to claim 5 .

7 . A method of producing a positive electrode active material, the method comprising:
(a) preparing a mixture by mixing a coating liquid and an active material particle; and (b) producing a positive electrode active material by drying the mixture, wherein the coating liquid includes a first solute or a second solute and a solvent, the first solute includes a glass network forming element, the first solute does not include phosphorus, the first solute satisfies a relationship of an expression (4):

0
≤

n
Li

/

n
E

≤
1

(
4
)

the second solute includes phosphorus and the glass network forming element,
the second solute satisfies a relationship of an expression (5):

0.11
≤

n
P

/

n
E

≤
9

(
5
)

in the above expression (4) and the above expression (5),
n Li represents a molarity of lithium in the coating liquid,
n E represents a molarity of the glass network forming element in the coating liquid, and
n P represents a molarity of phosphorus in the coating liquid.

8 . The method of producing a positive electrode active material according to claim 7 , wherein the glass network forming element is boron.

9 . The method of producing a positive electrode active material according to claim 7 , wherein the second solute further satisfies a relationship of an expression (6):

0
≤

n

Assignees

• Toyota Motor Co Ltd

Inventors

• Kubota Masaru

Classifications

• H01M10/0562

  Solid materials · CPC title

• H01M10/0525

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

• H01M10/052

  Li-accumulators · CPC title

• H01M4/13

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M4/624

  Electric conductive fillers · CPC title