Porous Binder Coating for Lithium Battery Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium secondary batteries face issues with weak adhesion strength between the electrode and separator, affecting battery performance and safety, particularly due to challenges in forming a thin, porous binder layer.
Innovation Solution
An electrode with a porous binder coating layer formed using a screen printing method with a mesh, utilizing a polyvinylidene fluoride (PVdF)-based polymer binder, applied in a thickness of 0.5 to 5 μm, which enhances adhesion while minimizing output degradation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a binder layer is formed by inducing phase separation on the separator surface, then adhesion strength between electrode and separator is improved, but the binder layer becomes difficult to thin
Solution Approach 1:
The invention changes the formation method parameter from phase separation induction to screen printing application, enabling precise control of binder layer thickness while maintaining adhesion strength. The screen printing method allows the binder layer to be formed at a controlled thickness of 0.5 to 5 μm, resolving the contradiction between achieving strong adhesion and maintaining thin layer structure.
2Power
If the binder layer is formed as a thin film for excellent battery output, then output performance is improved, but adhesion strength with separator deteriorates
Solution Approach 1:
The invention optimizes the binder layer thickness parameter to a specific range of 0.5 to 5 μm through screen printing, achieving a balance where the layer is thin enough to maintain excellent output performance while being thick enough to provide sufficient adhesion strength. This parameter optimization resolves the contradiction between output performance and adhesion strength.
Solution Approach 2:
The screen printing method uses a mesh structure that allows precise control of material deposition through controlled application and drying processes, enabling the formation of uniformly thin binder layers that maintain both electrical performance and mechanical adhesion.
3Strength
If the binder layer thickness is increased to improve adhesion, then adhesion strength is improved, but output performance deteriorates
Solution Approach 1:
The invention establishes an optimal thickness parameter range of 0.5 to 5 μm for the binder layer, which is thin enough to preserve output performance while sufficient for adhesion. This precise parameter control through screen printing resolves the contradiction by finding the optimal balance point between these two competing requirements.
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 porous binder coating layer improves adhesion strength between the electrode and separator, maintaining battery performance and safety while preventing output degradation.
Implementation Method 1
coating the binder emulsion acquired at step (S20) on a surface of the active material layer of the electrode in a screen printing method using a mesh to form a binder coating layer of a porous structure
Implementation Method 2
The coated mesh pattern may be dried during the rotation of the mesh roll and the winding of the electrode
Data Source
AI summary
An electrode with a porous binder coating layer may be manufactured in a method including (S10) a step of preparing the electrode including an active material layer formed on at least one surface of a current collector; (S20) a step of acquiring a binder emulsion by adding a binder to a dispersion medium; and (S30) a step of coating the binder emulsion acquired at the step (S20) on a surface of the active material layer of the electrode in a screen printing method using a mesh to form a binder coating layer of a porous structure.