Separator having high heat resistance, manufacturing method thereof and secondary battery including the same

Patent metadata

Field	Value
Publication number	US-2016149187-A1
Application number	US-201514918454-A
Country	US
Kind code	A1
Filing date	Oct 20, 2015
Priority date	Nov 21, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

Provided are a separator having high heat resistance, a manufacturing method thereof and a secondary battery including the separator. The separator includes a porous base layer, and a coating layer formed on at least one surface of the base layer. Here, the coating layer includes 5 wt % to 25 wt % of polyvinyl alcohol (PVA) or derivatives thereof as a first binder and 75 wt % to 95 wt % of polyacrylic acid (PAA) or derivatives thereof as a second binder.

First claim

What is claimed is:

1 . A separator comprising:
a porous base layer; and a coating layer formed on at least one surface of the base layer, wherein the coating layer includes 5 wt % to 25 wt % of polyvinyl alcohol (PVA) or derivatives thereof as a first binder and 75 wt % to 95 wt % of polyacrylic acid (PAA) or derivatives thereof as a second binder.

2 . The separator of claim 1 , wherein the coating layer further includes an inorganic layer, wherein a ratio of the first binder to the inorganic layer is in a range of 0.3 wt % to 1.6 wt %.

3 . The separator of claim 1 , wherein the coating layer further includes an inorganic layer, wherein a ratio of the first binder to the inorganic layer is in a range of 0.3125 wt % to 1.5625 wt %.

4 . The separator of claim 1 , wherein the coating layer further includes an inorganic layer, wherein a ratio of the second binder to the inorganic layer is in a range of 4.7 wt % to 5.9 wt %.

5 . The separator of claim 1 , wherein the coating layer further includes an inorganic layer, wherein a ratio of the second binder to the inorganic layer is in a range of 4.6875 wt % to 5.9375 wt %.

6 . The separator of claim 1 , wherein the coating layer further includes an inorganic layer and the inorganic layer is one selected from the group consisting of Al 2 O 3 , SiO 2 , TiO 2 , SnO 2 , CeO 2 , MgO, NiO, CaO, ZnO, ZrO 2 , Y 2 O 3 , SrTiO 3 , BaTiO 3 , Mg(OH) 2 and combinations thereof.

7 . The separator of claim 1 , wherein the coating layer further includes an acrylic acid series dispersing agent.

8 . The separator of claim 7 , wherein the dispersing agent is contained in an amount of 0.1% to 0.5% based on the weight of the inorganic layer.

9 . A secondary battery including the separator of claim 1 .

10 . A manufacturing method of a separator, comprising:
preparing a binder solution including a first binder containing 10 wt % to 25 wt % of polyvinyl alcohol (PVA) and a second binder containing 75 wt % to 95 wt % of polyacrylic acid (PAA) or derivatives thereof as a second binder; mixing inorganic particles with the binder solution and dispersing to form an inorganic slurry; and coating and the inorganic slurry on a surface of the base layer and drying the same to form an inorganic layer.

11 . The manufacturing method of claim 10 , wherein distilled water is further added to the binder solution to form the inorganic slurry in a ratio of 30% to 50% more than the inorganic particles.

12 . The manufacturing method of claim 10 , wherein a ratio of the first binder to the inorganic layer is in a range of 0.3 wt % to 1.6 wt %.

13 . The manufacturing method of claim 10 , wherein a ratio of the second binder to the inorganic layer is in a range of 4.7 wt % to 5.9 wt %.

14 . The manufacturing method of claim 10 , wherein a ratio of the first binder to the inorganic layer is in a range of 0.3125 wt % to 1.5625 wt %.

15 . The manufacturing method of claim 10 , wherein a ratio of the second binder to the inorganic layer is in a range of 4.6875 wt % to 5.9375 wt %.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Cho Byeonggyu
• Kim Hyungbae
• Lee Eungyeong
• In Jinhyuk
• Park Jonghwan

Classifications

• H01M50/403 Primary

  Manufacturing processes of separators, membranes or diaphragms · CPC title

• H01M50/457

  comprising three or more layers · 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

• H01M50/449

  having a layered structure · CPC title

• H01M2/166

  Electricity · mapped topic