Electrode and lithium secondary battery comprising same

Patent metadata

Field	Value
Publication number	US-11424441-B2
Application number	US-201816623844-A
Country	US
Kind code	B2
Filing date	Jun 27, 2018
Priority date	Jul 4, 2017
Publication date	Aug 23, 2022
Grant date	Aug 23, 2022

Abstract

An electrode including an additive for forming pores with an average particle diameter of 1 μm or greater, and a lithium secondary battery including the electrode. The porosity of the porous particles may be from 50% to 95%. The porosity of the electrode increases by including the additive for forming pores. As the porosity of the electrode increases by the additive for forming pores, and accordingly, effects of having excellent electrode reactivity and enhanced initial capacity are obtained even under high loading.

First claim

The invention claimed is:

1. A positive electrode for a lithium secondary battery, comprising:
a positive electrode active material;
a binder;
a conductor; and
an additive for forming pores,
wherein the additive comprises porous particles having an average particle diameter (D50) of 4 μm or greater, and wherein the additive is configured to form pores in the positive electrode, and
wherein the additive configured to form pores comprises carbon or graphite.

2. The positive electrode of claim 1 , wherein a porosity of the porous particles is from 50% to 95%.

3. The positive electrode of claim 1 , wherein a content of the additive configured to form pores is from 0.5% by weight to 5% by weight with respect to a total weight of the electrode.

4. The positive electrode of claim 1 , wherein the electrode has a porosity of 64% or greater.

5. The positive electrode of claim 1 , wherein the electrode active material is one or more positive electrode active materials selected from the group consisting of elemental sulfur (S8), a sulfur series compound and a mixture thereof.

6. The positive electrode of claim 1 , wherein the binder is one or more selected from the group consisting of styrene-butadiene rubber-carboxymethyl cellulose (SBR-CMC), poly(vinyl acetate), polyvinyl alcohol, polyethylene oxide, polyvinyl pyrrolidone, alkylated polyethylene oxide, crosslinked polyethylene oxide, polyvinyl ether, poly(methyl methacrylate), polyvinylidene fluoride, a copolymer of polyhexafluoropropylene and polyvinylidene fluoride, poly(ethyl acrylate), polytetrafluoroethylene, polyvinyl chloride, polyacrylonitrile, polyvinylpyridine, polystyrene, derivatives thereof, blends thereof and copolymers thereof.

7. The positive electrode of claim 1 , wherein the conductor is one or more selected from the group consisting of carbon-based materials selected from carbon black, acetylene black and ketjen black; and conducting polymers selected from polyaniline, polythiophene, polyacetylene and polypyrrole.

8. A lithium secondary battery comprising the positive electrode of claim 1 .

9. The lithium secondary battery of claim 8 , wherein the lithium secondary battery is a lithium-sulfur battery.

Assignees

• Lg Chemical Ltd
• Lg Energy Solution Ltd

Inventors

• Cho Eunkyung
• Kim Yun Kyoung
• Sohn Kwonnam
• Yang Doo Kyung

Classifications

• H01M4/624

  Electric conductive fillers · CPC title

• H01M4/622 Primary

  being polymers · CPC title

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/136

  Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy · CPC title