Electrode drying method capable of suppressing binder swelling and electrode drying system using same

Patent metadata

Field	Value
Publication number	US-12494474-B2
Application number	US-202117768716-A
Country	US
Kind code	B2
Filing date	Aug 20, 2021
Priority date	Oct 12, 2020
Publication date	Dec 9, 2025
Grant date	Dec 9, 2025

Abstract

An electrode drying method including: constant-rate-drying an electrode substrate coated with an electrode slurry while the electrode substrate is moved in a state that the electrode substrate makes a tilt angle with a horizontal plane; and falling-rate-drying the electrode substrate while the electrode substrate is horizontally moved. The electrode drying method and related system provide suppression of a floating phenomenon of binder elements during a drying process of an electrode and improve adhesive force between an electrode mixture layer and an electrode current collector.

First claim

The invention claimed is:

1 . A method for drying an electrode, the method comprising:
constant-rate-drying an electrode substrate coated with an electrode slurry while the electrode substrate is moved in a state that the electrode substrate makes a tilt angle with a horizontal plane; and falling-rate-drying the electrode substrate while the electrode substrate is horizontally moved, wherein the constant-rate-drying includes n sections, wherein a movement angle in a p-th section and a movement angle in a q-th section satisfy following condition 1:
|θ p−θQ|> 10(°),  [Condition 1]

wherein the θp denotes the movement angle in the p-th section, wherein θq denotes the movement angle in the q-th section, wherein the n is an integer equal to or greater than 2, and wherein each of the p and the q is an integer between 1 and the n, and the p is different from the q.

2 . The method of claim 1 , wherein during the constant-rate-drying of the electrode substrate, a movement angle between the electrode substrate and the horizontal plane is in a range of 10 to 350 degrees.

3 . The method of claim 1 , wherein during the constant-rate-drying of the electrode substrate, there are: (i) a section where a movement angle between the electrode substrate and the horizontal plane increases, (ii) a section where the movement angle is maintained, and (iii) a section where the movement angle decreases.

4 . The method of claim 1 , wherein the electrode substrate is dried by one or more of a hot air drying scheme, a heating coil drying scheme, or an induction-heat drying scheme during the constant-rate-drying of the electrode substrate; and the electrode substrate is dried by a light irradiation drying scheme during the falling-rate-drying of the electrode substrate.

5 . The method of claim 1 , wherein an average drying temperature T 1 during the constant-rate-drying of the electrode substrate is lower than an average drying temperature T 2 during the falling-rate-drying of the electrode substrate.

6 . The method of claim 1 , further comprising preliminary-drying the electrode substrate by heating the electrode substrate before the constant-rate-drying of the electrode substrate.

7 . The method of claim 1 , further comprising: coating an electrode slurry on the electrode substrate by applying the electrode slurry, which contains an active material, a binder polymer, and a solvent, on at least one surface of the electrode substrate,
wherein the coating of the electrode slurry, the constant-rate-drying of the electrode substrate, and the falling-rate-drying of the electrode substrate are consecutively.

8 . The method of claim 1 , wherein the electrode is a negative electrode.

9 . The method of claim 1 , further comprising: coating an electrode slurry on the electrode substrate by applying the electrode slurry, which contains an active material, a binder polymer, and a solvent, on at least one surface of the electrode substrate,
wherein the coating of the electrode slurry, the constant-rate-drying of the electrode substrate, and the falling-rate-drying of the electrode substrate are sequentially performed.

10 . A system for drying an electrode, the system comprising:
a conveyor line which is configured to be moved in a state that an electrode substrate, which is obtained by applying an electrode slurry on at least one surface of an electrode current collector, is disposed on the conveyor line; and a heating unit which is located on a moving path of the conveyor line is configured to heat an electrode sheet, wherein the conveyor line includes: a constant-rate-drying section where the conveyor line is configured to be moved while forming a tilt angle with a horizontal plane; and a falling-rate-drying section where the conveyor line is configured to be horizontally moved, at a region where the conveyor line passes through the heating unit, and wherein the constant-rate-drying section includes n sections, wherein a movement angle in a p-th section and a movement angle in a q-th section satisfy following condition 1:
|θ p−θq|> 10(°),  [Condition 1]

wherein the θp denotes the movement angle in the p-th section, wherein θq denotes the movement angle in the q-th section, wherein the n is an integer equal to or greater than 2, and wherein each of the p and the q is an integer between 1 and the n, and the p is different from the q.

11 . The system of claim 10 , further comprising an angle adjusting unit which is configured to control a movement angle of the conveyor line.

Assignees

• Lg Energy Solution Ltd

Inventors

• Lee Chang Ju
• Woo Sang Wook
• Noh Suk In

Classifications

• H01M4/0404

  by coating on electrode collectors · CPC title

• F26B15/18

  the objects or batches of materials being carried by endless belts · CPC title

• F26B3/347

  Electromagnetic heating, e.g. induction heating or heating using microwave energy · CPC title

• F26B3/30

  from infrared-emitting elements {(by radiation emanating from passages containing heated fluids other than combustion gases F26B23/10)} · CPC title

• F26B3/04

  the gas or vapour circulating over or surrounding the materials or objects to be dried (F26B3/14 takes precedence) · CPC title