Separator Surface Composition for Solvent-Free Lamination Adhesion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing separators for electrochemical devices face challenges in maintaining adhesive force during lamination and stacking processes without using organic solvents, which increases manufacturing costs and requires separate solvent treatment facilities.

Innovation Solution

A separator with a coating layer containing specific ratios of halogen and metal atoms, primarily fluorine and aluminum, on a porous polymer substrate, enhancing both dry and wet adhesive forces while eliminating the need for organic solvents in the manufacturing process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a binder resin is added to the slurry for the coating layer to secure adhesive force, then adhesive force between electrode and separator is improved, but manufacturing complexity increases due to additional materials and processing steps

Engineering Contradiction:
Improveadhesive forceVSAvoidmanufacturing complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The invention changes the surface composition parameters of the coating layer by controlling the content of halogen atoms (10% by weight or less) and metal atoms (20% by weight or more) exposed on the surface. This parameter adjustment enables the coating layer to achieve proper adhesive force for lamination and stacking processes without requiring additional binder resins, thus resolving the contradiction between adhesive force and manufacturing complexity

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The coating layer is formed as a composite material containing inorganic particles and polymer binder particles with specific surface composition. The composite structure with controlled surface exposure of halogen and metal atoms provides both the necessary adhesive force and eliminates the need for separate binder resin addition, reducing manufacturing complexity

Inventive Principle:
Principle #40Composite materials

2Ease of manufacture

If oil-based slurry coating using organic solvent such as acetone is used to form coating layer, then coating layer formation is achieved, but manufacturing cost increases and environmental restrictions apply due to organic solvent treatment facilities

Engineering Contradiction:
Improvecoating layer formationVSAvoidmanufacturing facility complexity
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The invention extracts and eliminates the organic solvent component from the slurry coating process. By formulating a solvent-free or water-based slurry that can still form a proper coating layer with the required surface composition (halogen atoms ≤10% by weight, metal atoms ≥20% by weight), the process removes the need for organic solvent treatment facilities, reducing manufacturing complexity and cost while maintaining coating layer formation capability

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention changes the slurry composition parameters by removing organic solvents and adjusting the formulation to use alternative vehicles (such as water or no solvent). This parameter change allows the slurry to maintain proper viscosity and coating properties without requiring organic solvent treatment facilities, resolving the contradiction between ease of manufacture and manufacturing facility complexity

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4425678A1Separator for electrochemical device and electrochemical device comprising same
Publication Date: 2024.09.04 LG ENERGY SOLUTION LTD
  • EP4425678A1 patent drawingFigure 1A~1B
  • EP4425678A1 patent drawingFigure 2
  • EP4425678A1 patent drawingFigure 3~4

AI summary

The present disclosure relates to a separator for an electrochemical device and an electrochemical device comprising the same, and specifically, to a separator for an electrochemical device, which adjusts the contents of halogen atoms and metal atoms exposed on the surface of a coating layer, thereby enabling a dry adhesive force and a wet adhesive force to be improved and the heat resistance of the separator to be improved, and an electrochemical device comprising the same.