Electrode Slurry Coating with Dual-Width Discharge Ports

Solution Overview

Problem

Existing coating devices struggle to uniformly apply thick active material layers on electrodes, leading to manufacturing inefficiencies and non-uniform electrode formation, particularly at the edge portions, which affects the charging and discharging efficiency of secondary batteries.

Innovation Solution

A coating device with multiple discharge ports of varying widths, including a narrower first discharge port for the edge portion and a wider second discharge port, is used to apply slurry layers sequentially, ensuring uniform coating by addressing sunken portions and edge irregularities.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the slurry is thickly discharged using the slot die coater, then the active material layer thickness is increased, but the electrode uniformity deteriorates

Engineering Contradiction:

Improveactive material layer thicknessVSAvoidelectrode uniformity

Core Design Contradiction:

Volume of moving objectVSManufacturing precision

Solution Approach 1:

The coating process is segmented into multiple stages with different discharge port widths. The slot die coater includes a first discharge port with width W1 and a second discharge port with width W2, where W1 < W2. The first discharge port applies slurry to edge portions with narrower width to prevent excess accumulation, while the second discharge port applies slurry to central portions with wider width to ensure sufficient coverage, thereby achieving uniform coating thickness without edge sinking

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the electrode receive different coating conditions tailored to their specific needs. Edge portions are coated through the narrower first discharge port to prevent excess slurry accumulation and sinking, while central portions are coated through the wider second discharge port to ensure adequate material coverage. This localized quality approach resolves the uniformity issue while maintaining overall thickness

Inventive Principle:

Principle #3Local quality

2Manufacturing precision

If the slurry is thinly discharged using the slot die coater, then the electrode uniformity is improved, but the manufacturing efficiency deteriorates

Engineering Contradiction:

Improveelectrode uniformityVSAvoidmanufacturing efficiency

Core Design Contradiction:

Manufacturing precisionVSProductivity

Solution Approach 1:

The coating process is segmented into multiple stages with different discharge port widths. The slot die coater includes a first discharge port with width W1 and a second discharge port with width W2, where W1 < W2. The first discharge port applies slurry to edge portions with narrower width to prevent excess accumulation, while the second discharge port applies slurry to central portions with wider width to ensure sufficient coverage, thereby achieving uniform coating thickness without edge sinking

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The dual discharge port configuration enables continuous coating of the entire electrode surface in a single pass. Both the first and second discharge ports operate simultaneously to coat edge and central portions respectively, eliminating the need for multiple sequential coating passes. This maintains high manufacturing efficiency while achieving uniform coating quality

Inventive Principle:

Principle #20Continuity of useful action

3Device complexity

If a single discharge port is used, then the device complexity is reduced, but the coating uniformity deteriorates

Engineering Contradiction:

Improvecoating device structureVSAvoidcoating uniformity

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The coating device is segmented into multiple discharge ports with different widths. The slot die coater includes a first discharge port with width W1 and a second discharge port with width W2, where W1 < W2. Each discharge port serves a specific function: the first for edge portions and the second for central portions. This segmentation enables uniform coating across the entire electrode surface while maintaining relatively simple device structure

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the electrode receive different coating conditions tailored to their specific needs. Edge portions are coated through the narrower first discharge port to prevent excess slurry accumulation and sinking, while central portions are coated through the wider second discharge port to ensure adequate material coverage. This localized quality approach resolves the uniformity issue while maintaining overall thickness

Inventive Principle:

Principle #3Local quality

Data Source

PatentEP4686510A1Coating device and electrode

Publication Date: 2026.02.04 SAMSUNG SDI CO LTD

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AI summary

A coating device and an electrode manufactured by the coating device are disclosed. A coating device includes a first discharge port configured to discharge a first slurry on a substrate to form a first coating layer, and a second discharge port that is spaced apart from the first discharge port and configured to discharge a second slurry on the first coating layer to form a second coating layer, and the first discharge port has a narrower width than the second discharge port.