Manufacturing method for electrode binder and electrode assembly comprising same electrode binder

Patent metadata

Field	Value
Publication number	US-2022173402-A1
Application number	US-202017600492-A
Country	US
Kind code	A1
Filing date	Jul 3, 2020
Priority date	Jul 15, 2019
Publication date	Jun 2, 2022
Grant date	—

Abstract

The present technology relates to a manufacturing method for an electrode binder, comprising a step of dissolving pelletized polyvinylidene fluoride (PVDF) in a solvent; and an electrode assembly comprising the electrode binder. The present invention may provide an electrode assembly which has a low content of impurities in a binder solution, is capable of increasing dispersibility of an electrode active material, and exhibits excellent binding force.

First claim

What is claimed is:

1 . A method for manufacturing an electrode binder, comprising:
dissolving granulated polyvinylidene fluoride (PVDF) in a solvent.

2 . The method of claim 1 , wherein:
the granulated polyvinylidene fluoride (PVDF) is in a form of granulated powdery particles, and an average diameter of the granulated powdery particles is in a range between 0.5 and 5 mm.

3 . The method of claim 1 , wherein a ratio of lengths of a long axis to a short axis of the granulated powdery particles is in a range between 20:1 and 1:1.

4 . The method of claim 2 , wherein the granulated powdery particles include: at least one of first powder particles having a weight average molecular weight (Mw) of 2.0×10 5 to 7.5×10 5 ; or second powder particles having a weight average molecular weight (Mw) of 7.5×10 6 to 2.5×10 6 .

5 . The method of claim 1 , wherein the solvent comprises a water-soluble solvent having a polar group.

6 . The method of claim 1 , wherein the solvent comprises at least one selected from the group consisting of acetone, tetrahydrofuran, methylene chloride, chloroform, dimethylformamide, N-methyl-2-pyrrolidone (NMP), cyclohexane, and water.

7 . The method of claim 1 , wherein a content of the granulated polyvinylidene fluoride (PVDF) dissolved in a solvent is in a range between 1 and 25% (w/w) with respect to a total weight of the solvent including the granulated polyvinylidene fluoride (PVDF).

8 . The method of claim 1 , further comprising: adding a conductive material after the dissolving granulated polyvinylidene fluoride (PVDF) in the solvent.

9 . An electrode composite comprising:
an electrode current collector; and an electrode composite layer coated on one side or both sides of the electrode current collector, wherein the electrode composite layer includes active material particles; a binder including polyvinylidene fluoride (PVDF); and a conductive material, the electrode composite layer includes pores in space between the active material particles, and the pores are filled with the binders and the conductive material, the pores have a porosity of 15 to 35% (v/v), and an average diameter of the pores is 0.01 to 1 mm.

10 . The electrode composite of claim 9 , wherein:
the active material particles include: first particles having an average particle diameter of 5 to 10 μm; and second particles having an average particle diameter of 100 to 200 μm based on a cross section of the electrode composite layer, and an area ratio of the first particles to the second particles is in a range between 1:1 and 10:1.

11 . The electrode composite of claim 9 , wherein:
a coating film having an average thickness of 50 to 150 μm is disposed on the electrode composite layer, and for specimens 2 cm wide and 20 cm long, adhesive force between the electrode current collector layer and the electrode composite layer is 100 N/m or more.

Assignees

• Lg Energy Solution Ltd

Inventors

• Jang Seong Keun
• Kim Woo Ha
• Choy Sang Hoon
• Kim In Seong
• Yoon Sung Pil

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01B1/20

  Conductive material dispersed in non-conductive organic material {(organic macromolecular compounds or compositions C08)} · CPC title

• H01G11/28

  arranged or disposed on a current collector; Layers or phases between electrodes and current collectors, e.g. adhesives · CPC title

• H01M4/366

  as layered products · CPC title

• H01M4/04

  Processes of manufacture in general · CPC title