Positive electrode having excellent alkali resistance, method of manufacturing the same, and metal-air battery and electrochemical device including the positive electrode

Patent metadata

Field	Value
Publication number	US-2021313569-A1
Application number	US-202117190785-A
Country	US
Kind code	A1
Filing date	Mar 3, 2021
Priority date	Apr 6, 2020
Publication date	Oct 7, 2021
Grant date	—

Abstract

A positive electrode includes a porous electroconductive metal oxide represented by Formula 1, wherein the electroconductive metal oxide has a specific surface area of about 0.01 m2/g to about 1000 m2/g,LxRuyOx   Formula 1wherein, in Formula 1,L is at least one of a lanthanide element or an actinide element, and0<x<1, 0<y<1, and 0<z≤1.

First claim

What is claimed is:

1 . A positive electrode comprising:
a porous electroconductive metal oxide represented by Formula 1, wherein the electroconductive metal oxide has a specific surface area of about 0.01 square meter per gram to about 1000 square meters per gram,
L x Ru y O z   Formula 1

wherein, in Formula 1,
L is at least one of a lanthanide element or an actinide element, and
0<x<1, 0<y<1, and 0<z≤1.

2 . The positive electrode of claim 1 , wherein, in Formula 1, L is at least one of lanthanum, cerium, praseodymium, neodymium, promethium, actinium, thorium, or protactinium.

3 . The positive electrode of claim 1 , wherein the electroconductive metal oxide represented by Formula 1 is La x Ru y O z , wherein 0<x<1, 0<y<1, and 0<z≤1.

4 . The positive electrode of claim 1 , wherein the electroconductive metal oxide represented by Formula 1 comprises at least one of La 7/26 Ru 4/13 O, La 1/3 Ru 1/3 O, La 2/5 Ru 1/5 O, or La 3/7 Ru 1/7 O.

5 . The positive electrode of claim 1 , wherein the electroconductive metal oxide represented by Formula 1 has a perovskite crystal structure.

6 . The positive electrode of claim 1 , wherein the electroconductive metal oxide represented by Formula 1 has a crystal structure comprising an orthorhombic phase, a monoclinic phase, a hexagonal phase, or a tetragonal phase.

7 . The positive electrode of claim 1 , wherein a pH inside the positive electrode is in a range of about 8 to about 14 during discharge.

8 . The positive electrode of claim 1 , wherein the electroconductive metal oxide represented by Formula 1 exhibits diffraction peaks at diffraction angles of about 25.2° 2θ, about 31.0° 2θ, about 32.0° 2θ, about 33.0° 2θ, and about 45.5° 2θ, diffraction peaks at diffraction angles of about 28.5° 2θ, about 30.7° 2θ, about 34.0° 2θ, about 39.5° 2θ, about 40.6° 2θ or a combination thereof, when analyzed by X-ray diffraction using Cu Kα radiation.

9 . The positive electrode of claim 1 , wherein an electronic conductivity at 25° C. of the positive electrode comprising the metal oxide is about 1×10 1 siemens per centimeter to about 1×10 8 siemens per centimeter.

10 . The positive electrode of claim 1 , wherein an ionic conductivity at 25° C. of the positive electrode comprising the metal oxide is about 1×10 −9 siemens per centimeter to about 1×10 −2 siemens per centimeter.

11 . The positive electrode of claim 1 , wherein the electroconductive metal oxide represented by Formula 1 has an average particle diameter of about 1 nanometer to about 1,000 nanometers.

12 . The positive electrode of claim 1 , wherein the positive electrode has at least one of a porous form, a planar form, or a tubular form.

13 . The positive electrode of claim 1 , wherein the metal oxide has a porosity of 0.01 to 0.8.

14 . The positive electrode of claim 1 , wherein the electroconductive metal oxide represented by Formula 1 is represented by at least one of La 3/7 Ru 1/7 O or La 1/3 Ru 1/3 O.

15 . A method of manufacturing the positive electrode of claim 1 , the method comprising:
mixing an L-containing compound containing at least one of a lanthanide element and an actinide element, a ruthenium-containing compound, and a solvent to obtain a mixture; and heat-treating the mixture to prepare the positive electrode.

16 . The method of claim 15 , wherein the heat-treating further comprises:
a first heat-treating of the mixture to form a first heat-treatment product; and a second heat-treating of the first heat-treatment product.

17 . The method of claim 16 , wherein the second heat-treating comprises heat-treating at a temperature higher than a temperature of the first heat-treating.

18 . The method of claim 16 , wherein
the first heat-treating comprises heat-treating at a temperature of about 500° C. to about 1000° C., and the second heat-treating is performed at a temperature of about 1000° C. to about 1700° C.

19 . The method of claim 15 , wherein the L-containing compound is at least one of an L-containing oxide, an L-containing carbonate, an L-containing chloride, an L-containing phosphate, an L-containing nitrate, or an L-containing hydroxide.

20 . The method of claim 15 , wherein the ruthenium-containing compound is a ruthenium oxide.

21 . A metal-air battery comprising:
a positive electrode layer comprising the positive electrode according to claim 1 as a positive electrode support and a positive electrode active material comprising oxygen; a negative electrode layer comprising at least one of a metal or a metal alloy; and an electrolyte disposed between the positive electrode layer and the negative electrode layer.

22 . The metal-air battery of claim 21 , wherein the negative electrode layer comprises at least one of lithium or a lithium alloy.

23 . The metal-air battery of claim 21 , wherein the electrolyte comprises at least one of a solid electrolyte or a liquid electrolyte.

24 . The metal-air battery of claim 21 , wherein the electrolyte comprises at least one of an aqueous solution or an aqueous vapor.

25 . An electrochemical device comprising the positive electrode of claim 1 .

26 . The electrochemical device of claim 25 , wherein the electrochemical device comprises at least one of a battery, an accumulator, a supercapacitor, a fuel cell, a sensor, or an electrochromic device.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Choi Wonsung
• Choi Kyounghwan
• Kim Mokwon
• Lee Hyunpyo

Classifications

• H01M12/06

  with one metallic and one gaseous electrode · CPC title

• H01M4/9016 Primary

  Oxides, hydroxides or oxygenated metallic salts · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/8605 Primary

  Porous electrodes · CPC title

• H01M12/08

  composed of a half-cell of a fuel-cell type and a half-cell of the secondary-cell type · CPC title