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

Patent metadata

Field	Value
Publication number	US-2024332508-A1
Application number	US-202418616540-A
Country	US
Kind code	A1
Filing date	Mar 26, 2024
Priority date	Mar 28, 2023
Publication date	Oct 3, 2024
Grant date	—

Abstract

A positive electrode active material includes: an active material particle; and a coating film. The coating film covers at least a part of a surface of the active material particle. The coating film contains P, B and O as components and further contains Li and Na as optional components. The positive electrode active material satisfies relationships of “formula (1): C Li /(C P +C B )≤1.50” and “formula (2): C Na /(C P +C B )≤1.34”. C Li , C P , C B and C Na represent respective element concentrations each measured by X-ray photoelectron spectroscopy. C Li represents an element concentration of lithium. C P represents an element concentration of phosphorus. C B represents an element concentration of boron. C Na represents an element concentration of lithium.

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 a part of a surface of the active material particle, the coating film contains P, B and O as components and further contains Li and Na as optional components, the positive electrode active material satisfies relationships of the following formula (1) and formula (2):

C
Li

/

(

C
P

+

C
B

)

≤
1.5

(
1
)

C
Na

/

(

C
P

+

C
B

)

≤
1.34

,

(
2
)

in the formula (1) and the formula (2),
C Li , C P , C B and C Na represent respective element concentrations each measured by X-ray photoelectron spectroscopy, and
C Li represents an element concentration of lithium, C P represents an element concentration of phosphorus, C B represents an element concentration of boron, and C Na represents an element concentration of sodium.

2 . The positive electrode active material according to claim 1 , wherein
the coating film contains Na as a component, and the positive electrode active material satisfies relationships of the following formula (3) and formula (4):

C
Li

/

(

C
P

+

C
B

)

≤
1.27

(
3
)

0.24
≤

C
Na

/

(

C
P

+

C
B

)

.

(
4
)

3 . The positive electrode active material according to claim 1 , wherein the positive electrode active material has a coverage of 94% or more, and
the coverage is measured by the X-ray photoelectron spectroscopy.

4 . An all-solid-state battery comprising:
a positive electrode; and a negative electrode, wherein the positive electrode includes the positive electrode active material according to claim 1 and a sulfide solid electrolyte.

5 . A method of manufacturing a positive electrode active material, the method comprising:
(a) preparing a mixture by mixing a coating liquid and an active material particle; and (b) manufacturing the positive electrode active material by drying the mixture, wherein the coating liquid includes a solute and a solvent, and the solute contains a phosphate compound and a borate compound as components, and contains, as an optional component, at least one selected from a group consisting of a lithium compound, a sodium salt and an ammonium salt.

Assignees

• Toyota Motor Co Ltd

Inventors

• Kubota Masaru

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M10/054

  Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium · CPC title

• H01M10/0525 Primary

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

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M4/366 Primary

  as layered products · CPC title