Lithium secondary battery negative electrode including protection layer made of conductive fabric, and lithium secondary battery including same

Patent metadata

Field	Value
Publication number	US-2020235385-A1
Application number	US-201716328625-A
Country	US
Kind code	A1
Filing date	Sep 27, 2017
Priority date	Sep 30, 2016
Publication date	Jul 23, 2020
Grant date	—

Abstract

A negative electrode for a lithium secondary battery including a protective layer formed with a conductive fabric, in particular, to a negative electrode for a lithium secondary battery including a conductive fabric formed on at least one surface of the lithium metal layer and having pores, and a lithium secondary battery including the same. The lithium secondary battery including a negative electrode having the conductive fabric as a protective layer that induces uniform reactions within the pores, thus preventing local lithium metal formation on the lithium metal surface, and thereby suppressing dendrite formation on the lithium metal surface, and thereby suppressing dendrite formation and cell volume expansion. In addition thereto, mechanical stability can be maintained even when lithium plating and stripping occurs due to the flexibility and tension/contraction of the conductive fabric.

First claim

1 . A negative electrode for a lithium secondary battery comprising:
a lithium metal layer; and a protective layer formed on at least one surface of the lithium metal layer, wherein the protective layer comprises a conductive fabric with pores formed therein.

2 . The negative electrode for a lithium secondary battery of claim 1 , wherein the conductive fabric comprises
a thread-weaved base fabric, wherein thread of the thread-weaved base fabric has a metal material coating on an outer surface of the thread, and a carbon material coating on an outer surface of the metal material coating.

3 . The negative electrode for a lithium secondary battery of claim 1 , wherein the conductive fabric has a pore size of 1 μm to 10,000 μm.

4 . The negative electrode for a lithium secondary battery of claim 1 , wherein the conductive fabric has a porosity of 5% to 50%.

5 . The negative electrode for a lithium secondary battery of claim 1 , wherein the conductive fabric has a thickness of 0.01 μm to 50 μm.

6 . The negative electrode for a lithium secondary battery of claim 1 , wherein the conductive fabric has a sheet resistance of 0.001 ohmn/sq to 1 ohmn/sq.

7 . The negative electrode for a lithium secondary battery of claim 2 , wherein the thread is one or more types selected from the group consisting of polyester, polyamide, polyethylene, polyurethane, polypropylene, polyurea, cotton, wool, silk and linen.

8 . The negative electrode for a lithium secondary battery of claim 2 , wherein the metal material is one or more types selected from the group consisting of nickel (Ni), copper (Cu), aluminum (Al), gold (Au), silver (Ag), zinc (Zn) and tin (Sn).

9 . The negative electrode for a lithium secondary battery of claim 2 , wherein the metal material is coated in 30 parts by weight to 70 parts by weight with respect to 100 parts by weight of the base fabric.

10 . The negative electrode for a lithium secondary battery of claim 2 , wherein the carbon material is one or more types selected from the group consisting of graphite-based material; active carbon-based material; carbon black-based material; carbon nanostructure-based material; and combinations thereof.

11 . The negative electrode for a lithium secondary battery of claim 2 , wherein the carbon material is coated in 20 parts by weight to 50 parts by weight with respect to 100 parts by weight of the base fabric.

12 . A lithium secondary battery comprising:
a negative electrode; a positive electrode; and an electrolyte provided therebetween, wherein the negative electrode is the negative electrode of claim 1 .

13 . The negative electrode for a lithium secondary battery of claim 10 ,
wherein the graphite-based material is natural graphite, artificial graphite, expanded graphite, graphene, Super-P or Super-C, wherein the carbon black-based material is denka black, ketjen black, channel black, furnace black, thermal black, contact black, lamp black or acetylene black, wherein the carbon nanostructure-based material is carbon fiber-based, carbon nanotubes (CNT) or fullerene.

14 . The negative electrode for a lithium secondary battery of claim 1 , wherein the conductive fabric comprises
a thread-weaved base fabric, wherein the thread of the thread-weaved base fabric has a metal material coating on an outer surface of the thread, and space between the treats is continuously coated or filled with a carbon material.

Assignees

• Lg Chemical Ltd

Inventors

• Kim Yeeun

Classifications

• H01M50/491

  Porosity · CPC title

• H01M50/489

  Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties · CPC title

• H01M4/663 Primary

  containing carbon or carbonaceous materials as conductive part, e.g. graphite, carbon fibres · CPC title

• H01M50/46

  Separators, membranes or diaphragms characterised by their combination with electrodes · CPC title

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title