Multi-Layer Die Coater With Insulating Liquid Slits

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing die coaters face challenges in simultaneously coating a current collector for secondary batteries with two different liquids in multiple layers, particularly due to sliding issues at the corners of the active material layer, which can lead to lithium precipitation and safety risks.

Innovation Solution

A die coater design that includes a first body with a first manifold for electrode slurry, a second body with a second manifold, and a third body forming separate slits for electrode slurry and insulating liquid, with adjustable shim configurations to control the position and number of insulating liquid slits, ensuring physical separation and controlled discharge of the liquids.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single die coater is used to coat multiple layers of active materials, then device complexity is reduced, but manufacturing precision deteriorates due to repeated manual die changes

Engineering Contradiction:
Improvenumber of die coatersVSAvoidcoating quality consistency
Core Design Contradiction:
Device complexityVSManufacturing precision

Solution Approach 1:

The patent combines multiple die coaters (first die coater and second die coater) into a single integrated device that can perform sequential coating operations. The first die coater applies a first active material layer, and the second die coater applies a second active material layer, both within the same coating chamber without requiring manual die changes. This merging approach maintains manufacturing precision while enabling multi-layer coating capability.

Inventive Principle:
Principle #5Merging (Combining)

2Manufacturing precision

If multiple die coaters are used to maintain coating quality for each layer, then manufacturing precision is improved, but device complexity increases

Engineering Contradiction:
Improvecoating quality consistencyVSAvoidnumber of die coaters
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent designs the die coater system with universal functionality where a single integrated die coater can perform multiple coating operations for different active material layers. The system includes a first die coater and a second die coater that can be sequentially operated within the same coating chamber, allowing one device to fulfill the role of multiple specialized die coaters while maintaining coating quality consistency across all layers.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If manual die changes are performed between layers, then adaptability is maintained, but productivity decreases due to additional time consumption

Engineering Contradiction:
Improveflexibility in coating different materialsVSAvoidcoating speed
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The patent implements preliminary action by pre-positioning multiple dies (first die and second die) within the coating chamber before the coating process begins. The dies are arranged such that the first die is initially positioned for coating the first active material layer, and the second die is pre-positioned for subsequent coating of the second active material layer. This eliminates the need for manual die changes during operation, maintaining adaptability while significantly improving productivity by reducing time consumption.

Inventive Principle:
Principle #10Preliminary action

4Adaptability or versatility

If the coating chamber is opened for die changes, then adaptability is maintained, but harmful factors increase due to exposure to air

Engineering Contradiction:
Improveability to change coating materialsVSAvoidbacterial growth and oxidation
Core Design Contradiction:
Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The system pre-positions multiple dies within the sealed coating chamber before the coating process begins. This preliminary arrangement allows the coating chamber to remain closed throughout the entire multi-layer coating process, preventing exposure to air that would cause bacterial growth and oxidation. The pre-positioned dies can be sequentially used without opening the chamber, maintaining adaptability for different coating materials while eliminating harmful environmental exposures.

Inventive Principle:
Principle #10Preliminary action

5Productivity

If multiple active material layers are coated sequentially in the same chamber, then productivity is improved, but manufacturing precision may deteriorate due to contamination risks

Engineering Contradiction:
Improvecoating efficiencyVSAvoidpurity of each layer
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The patent segments the coating process by providing separate, dedicated die coaters (first die coater and second die coater) for coating different active material layers. Each die coater operates independently within the same chamber, and the system includes mechanisms to prevent cross-contamination between layers. This segmentation approach maintains the purity of each layer while enabling efficient sequential coating operations that improve overall productivity.

Inventive Principle:
Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The die coater enables simultaneous multi-layer coating of electrode slurry and insulating liquid, minimizing mixing and leakage, effectively controlling sliding phenomena, and enhancing safety by preventing lithium precipitation.

Implementation Method 1

a doctor blade may be used to remove excess slurry

Methodology Applied
Scientific EffectCapillary action: Capillary Action

Data Source

PatentEP4321264B1Die coater capable of multi-layer coating of active materials
Publication Date: 2026.04.29 LG ENERGY SOLUTION LTD
  • EP4321264B1 patent drawingFigure 1
  • EP4321264B1 patent drawingFigure 2
  • EP4321264B1 patent drawingFigure 3~4

AI summary

A die coater capable of simultaneously coating a current collector with two different liquids in multiple layers includes a first body with a first manifold for an electrode slurry, a second body with a second manifold coupled to the first body to form a first slit through which the electrode slurry in the first manifold is discharged, and a third body coupled to the second body to form a second slit through which the electrode slurry in the second manifold is discharged. The first slit is formed by a first and third shim that are interposed between coupling surfaces of the first and second body, and the second slit is formed by a second and fourth shim that are interposed between coupling surfaces of the second and third body, and at least any one of the third shim and the fourth shim forms an insulating liquid slit.