Positive electrode of lithium-air battery having side reaction prevention film to which metal catalyst is partially introduced, lithium-air battery having same, and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-10505203-B2
Application number	US-201715743387-A
Country	US
Kind code	B2
Filing date	Jan 16, 2017
Priority date	Jan 20, 2016
Publication date	Dec 10, 2019
Grant date	Dec 10, 2019

Abstract

The present invention relates to a positive electrode of a lithium-air battery having a side reaction prevention layer with a partially introduced metal catalyst, and a method for preparing the same, and in particular, to a positive electrode of a lithium-air battery having a side reaction prevention layer with a metal catalyst sporadically partially introduced to a surface thereof, and a method for preparing the same. The lithium-air battery according to the present invention suppresses a side reaction at an interface between a positive electrode active material and an electrolyte thereby effectively reduces an overvoltage when charged, and therefore, does not cause liquid electrolyte decomposition, which is effective in enhancing a cycle life.

First claim

The invention claimed is:

1. A positive electrode for a lithium-air battery comprising:
a porous current collector;
a carbon-based conductor and binder coated directly on a surface of the porous current collector;
a side reaction prevention layer coated directly on an outer surface of the carbon-based conductor; and
a metal catalyst sporadically on an outer surface of the side reaction prevention layer,
wherein the side reaction prevention layer includes a conductive metal oxide.

2. The positive electrode for a lithium-air battery of claim 1 , wherein the conductive metal oxide includes one type selected from the group consisting of indium tin oxide, indium zinc oxide, antimony tin oxide, fluorinated tin oxide, aluminum zinc oxide, magnesium indium oxide, zinc gallium oxide, gallium indium oxide, indium-gallium-zinc oxide, niobium-strontium-titanium oxide, indium cadmium oxide, BZO, SZO, indium oxide and combinations thereof.

3. The positive electrode for a lithium-air battery of claim 1 , wherein the side reaction prevention layer has a thickness of 5 nm˜30 nm.

4. The positive electrode for a lithium-air battery of claim 1 , wherein the carbon-based conductor includes one type selected from the group consisting of graphite-based, active carbon-based, carbon black-based, carbon fiber, carbon nanostructures and combinations thereof.

5. The positive electrode for a lithium-air battery of claim 1 , wherein the metal catalyst is ruthenium, palladium, platinum, gold, nickel, copper, silver, zinc, lead, cadmium, tin, titanium and an alloy thereof, an oxide thereof, a sulfide thereof or a selenide thereof.

6. The positive electrode for a lithium-air battery of claim 1 , wherein the metal catalyst is included in 10˜50 parts by weight with respect to 100 parts by weight of the carbon-based conductor.

7. The positive electrode for a lithium-air battery of claim 1 , wherein the metal catalyst has an average particle diameter of 1 nm˜10 nm.

8. A method for preparing a positive electrode for a lithium-air battery comprising:
i) coating a carbon-based conductor and binder directly on a porous current collector;
ii) depositing a side reaction prevention layer directly on an outer surface of the carbon-based conductor; and
iii) introducing a metal catalyst on an outer surface of the side reaction prevention layer,
wherein the side reaction prevention layer includes a conductive metal oxide.

9. The method for preparing a positive electrode for a lithium-air battery of claim 8 , wherein the deposition in ii) is carried out using sputtering or thermal evaporation deposition.

10. The method for preparing a positive electrode for a lithium-air battery of claim 8 , wherein the conductive metal oxide includes one type selected from the group consisting of indium tin oxide, indium zinc oxide, antimony tin oxide, fluorinated tin oxide, aluminum zinc oxide, magnesium indium oxide, zinc gallium oxide, gallium indium oxide, indium-gallium-zinc oxide, niobium-strontium-titanium oxide, indium cadmium oxide, BZO, SZO, indium oxide and combinations thereof.

11. A lithium-air battery comprising:
a lithium negative electrode;
a positive electrode;
a separator provided therebetween; and
an electrolyte,
wherein the positive electrode is the positive electrode for a lithium-air battery of claim 1 .

Assignees

• Lg Chemical Ltd

Inventors

• Lee Dong Wook
• Lyu Byung Gook
• Han Jae Sung
• Chae Jong Hyun
• Yang Doo Kyung
• Cho Eun Kyung

Classifications

• H01M4/382

  Lithium (H01M4/405 takes precedence) · CPC title

• H01M4/8657

  layered · CPC title

• H01M4/8673

  Electrically conductive fillers · CPC title

• H01M2004/8689

  Positive electrodes · CPC title

• H01M4/8668

  Binders · CPC title