Porous separator and lithium secondary battery comprising same

Patent metadata

Field	Value
Publication number	US-12002990-B2
Application number	US-201917279070-A
Country	US
Kind code	B2
Filing date	Oct 11, 2019
Priority date	Oct 12, 2018
Publication date	Jun 4, 2024
Grant date	Jun 4, 2024

Abstract

The present invention relates to a porous separator comprising a porous layer containing a plurality of plate-type inorganic particles and a first binder polymer positioned on part or all of the surface of the plate-type inorganic particles to connect and fix between the plate-type inorganic particles; and a metal layer formed on any one surface of the porous layer, and a lithium secondary battery comprising the same.

First claim

The invention claimed is:

1. A porous separator comprising:
a porous layer containing a plurality of plate-shaped inorganic particles and a first binder polymer positioned on a part or all of a surface of the plate-shaped inorganic particles to connect and fix between the plate-shaped inorganic particles;
a metal layer disposed on a surface of the porous layer; and
a ceramic coating layer disposed on another surface of the porous layer which is opposite to the surface on which the metal layer is disposed,
wherein the porous separator does not include a polymer other than the first binder polymer, and
the ceramic coating layer includes BaSrTiO 3 or PbLaZrTiO 3 .

2. The porous separator according to claim 1 , wherein the plate-shaped inorganic particles comprise alumina, silica, zirconia, titanium dioxide, magnesia, ceria, yttrium oxide, zinc oxide, iron oxide, barium titanium oxide, alumina-silica composite oxide, or a mixture of two or more thereof.

3. The porous separator according to claim 1 , wherein an aspect ratio of the plate-shaped inorganic particles is 5 to 100.

4. The porous separator according to claim 1 , wherein an aspect ratio of the plate-shaped inorganic particles is 50 to 100.

5. The porous separator according to claim 1 , wherein the metal layer contains metal (M) capable of reacting with lithium to form an alloy of Li x M, wherein x is 1 to 2.25.

6. The porous separator according to claim 1 , wherein the metal layer contains at least one metal selected from the group consisting of Al, In, Au, Ni, and Mg.

7. The porous separator according to claim 1 , wherein the metal layer has a thickness of 0.01 to 1 μm.

8. The porous separator according to claim 1 , wherein the ceramic coating layer has a dielectric constant of 20 to 1000.

9. The porous separator according to claim 1 , wherein the porous layer further contains spherical inorganic particles.

10. The porous separator according to claim 1 , wherein a weight of the first binder polymer relative to a total weight of the porous layer is 0.1 to 30% by weight.

11. The porous separator according to claim 1 , wherein the ceramic coating layer further includes HfO 2 .

12. The porous separator according to claim 1 , wherein the ceramic coating layer further includes ZrO 2 .

13. A lithium secondary battery comprising a positive electrode, a negative electrode, and the porous separator of claim 1 interposed between the positive electrode and the negative electrode.

14. The lithium secondary battery according to claim 13 , wherein the negative electrode and the metal layer of the porous separator are in contact with each other.

15. The lithium secondary battery according to claim 13 , wherein the lithium secondary battery comprises lithium metal or lithium alloy in the negative electrode.

Assignees

• Lg Chemical Ltd
• Lg Energy Solution Ltd

Inventors

• Choi Woongchul
• Choi Junghun
• Kang Yonghee
• Jang Minchul
• Youn Suk Il
• Son Byoungkuk

Classifications

• H01M10/0525

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

• H01M50/434

  Ceramics · CPC title

• H01M50/446

  Composite material consisting of a mixture of organic and inorganic materials · CPC title

• H01M50/431

  Inorganic material · CPC title