Method for producing electrode, electrode, and electrode-electrolyte layer assembly

Patent metadata

Field	Value
Publication number	US-2019207248-A1
Application number	US-201816232600-A
Country	US
Kind code	A1
Filing date	Dec 26, 2018
Priority date	Dec 28, 2017
Publication date	Jul 4, 2019
Grant date	—

Abstract

A method for producing an electrode comprising a porous garnet-type ion-conducting oxide sintered body with high ion conductivity, the electrode, and an electrode-electrolyte layer assembly comprising the electrode and an electrolyte layer comprising a dense garnet-type ion-conducting oxide sintered body with high ion conductivity. Disclosed is a method for producing an electrode, the method comprising: preparing crystal particles of a garnet-type ion-conducting oxide; preparing a lithium-containing flux; preparing the electrode active material; preparing an electrolyte material by mixing the crystal particles of the garnet-type ion-conducting oxide and the flux; and sintering the electrolyte material and the electrode active material by heating at a temperature of 650° C. or less, wherein a number average particle diameter of the flux is larger than a number average particle diameter of the crystal particles of the garnet-type ion-conducting oxide.

First claim

1 . A method for producing an electrode comprising a first oxide electrolyte sintered body and an electrode active material,
the method comprising: preparing crystal particles of a garnet-type ion-conducting oxide represented by the following general formula (A):
(Li x−3y−z , E y , H z )L α M β O γ   General Formula (A)

where E is at least one kind of element selected from the group consisting of Al, Ga, Fe and Si; L is at least one kind of element selected from the group consisting of an alkaline-earth metal and a lanthanoid element; M is at least one kind of element selected from a transition element that can be six-coordinated with oxygen and typical elements in groups 12 to 15 of the periodic table; x, y and z are real numbers satisfying 3≤x−3y−z≤7, 0≤y<0.22 and 0<z≤3.4; and α, β and γ are real numbers in ranges of 2.5≤α≤3.5, 1.5≤β≤2.5 and 11≤γ≤13, respectively;
preparing a lithium-containing flux;
preparing the electrode active material;
preparing an electrolyte material by mixing the crystal particles of the garnet-type ion-conducting oxide and the flux; and
sintering the electrolyte material and the electrode active material by heating at a temperature of 650° C. less,
wherein a number average particle diameter of the flux is larger than a number average particle diameter of the crystal particles of the garnet-type ion-conducting oxide.

2 . An electrode comprising a first oxide electrolyte sintered body and an electrode active material,
wherein the first oxide electrolyte sintered body has grain boundaries between crystal particles of a garnet-type ion-conducting oxide represented by the following general formula (B):
(Li x−3y−z , E y , H z )L α M β O γ   General Formula (B)

where E is at least one kind of element selected from the group consisting of fil, Ga, Fe and Si; L is at least one kind of element selected from the group consisting of an alkaline-earth metal and a lanthanoid element; M is at least one kind of element selected from a transition element that can be six-coordinated with oxygen and typical elements in groups 12 to 15 of the periodic table; x, y and z are real numbers satisfying 3≤x−3y−z≤7, 0≤y<0.22 and 0≤z<3.4; and α, β and γ are real numbers in ranges of 2.5≤α≤3.5, 1.5≤β≤2.5 and 11≤γ≤13, respectively;
wherein a lithium-containing flux is present at grain boundary triple junctions between the crystal particles; and
wherein the first oxide electrolyte sintered body is a porous body having a voidage of 27% or more.

3 . An electrode comprising a first oxide electrolyte sintered body and an electrode active material,
wherein the first oxide electrolyte sintered body has grain boundaries between crystal particles of a garnet-type ion-conducting oxide represented by the following general formula (B):
(Li x−3y−z , E y , H z )L α M β O γ   General Formula (B)

where E is at least one kind of element selected from the group consisting of Al, Ga, Fe and Si; L is at least one kind of element selected from the group consisting of an alkaline-earth metal and a lanthanoid element; M is at least one kind of element selected from a transition element that can be six-coordinated with oxygen and typical elements in groups 12 to 15 of the periodic table; x, y and z are real numbers satisfying 3≤x−3y−z≤7, 0≤y<0.22 and 0≤z<3.4; and α, β and γ are real numbers in ranges of 2.5≤α≤3.5, 1.5≤β≤2.5 and 11≤γ≤13, respectively;
wherein a number average particle diameter of the crystal particles is 3 μm or less; and
wherein the first oxide electrolyte sintered body is a porous body having a voidage of 27% or more.

4 . The electrode according to claim 2 , wherein y in the general formula (B) is in a range of 0.13<y<0.22.

5 . An electrode-electrolyte layer assembly comprising the electrode defined by claim 4 and an electrolyte layer comprising a second oxide electrolyte sintered body,
wherein the second oxide electrolyte sintered body has grain boundaries between crystal particles of a garnet-type ion-conducting oxide represented by the following general formula (C):
(Li x−3y−z , E y , H z )L α d M β O γ   General Formula (C)

where E is at least one kind of element selected from the group consisting of Al, Ga, Fe and Si; L is at least one kind of element selected from the group consisting of an alkaline-earth metal and a lanthanoid element; M is at least one kind of element selected from a transition element that can be six-coordinated with oxygen and typical elements in groups 12 to 15 of the periodic table; x, y and z are real numbers satisfying 3≤x−3y−z≤7, 0≤y<0.22 and 0≤z<3.4; and α, β and γ are real numbers in ranges of 2.5≤α≤3.5, 1.5≤β≤2.5 and 11≤γ≤13, respectively, and
wherein a lithium-containing flux is present at grain boundary triple junctions between the crystal particles.

6 . The electrode-electrolyte layer assembly according to claim 5 , wherein y in the general formula (C) is in a range of 0≤y≤0.13.

Assignees

• Toyota Motor Co Ltd

Inventors

• Ohta Shingo

Classifications

• H01M10/0525

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

• H01M4/13

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

• H01M4/139

  Processes of manufacture · CPC title

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title

• H01M10/058

  Construction or manufacture · CPC title