Solvent-Free Electrode Formulation via Extruded PTFE Fibrils
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current lithium-ion battery electrode production is energy-intensive and environmentally unfriendly due to the use of solvent-based methods, which are costly and incompatible with continuous industrial operations, and can damage fragile active materials like graphite.
Innovation Solution
A solvent-free method involving the preparation of a pre-mix with an active electrode material and a fibrillable fluoropolymer, such as PTFE, followed by mixing with a co-binder like TPU and extrusion to create fibrils that form a porous network, reducing the need for solvents and improving mechanical strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If solvent-based methods are used to prepare electrode formulations, then the coating process can be performed, but energy consumption increases due to solvent evaporation requiring ovens
Solution Approach 1:
The invention extracts and removes the solvent component from the electrode formulation, transitioning from a solvent-based slurry to a solvent-free dry mixture. This eliminates the need for energy-consuming evaporation ovens while maintaining the coating process through alternative binding mechanisms using fluoropolymer and co-binder materials.
Solution Approach 2:
The invention changes the physical and chemical parameters of the electrode formulation by replacing the solvent medium with a dry powder mixture containing fluoropolymer and co-binder. This parameter change enables the coating process to proceed without thermal evaporation, fundamentally altering the manufacturing energy requirements.
2Ease of manufacture
If solvent-based methods are used to prepare electrode formulations, then the coating process can be performed, but production costs increase
Solution Approach 1:
The invention extracts and removes the solvent component from the electrode formulation, transitioning from a solvent-based slurry to a solvent-free dry mixture. This eliminates the need for energy-consuming evaporation ovens while maintaining the coating process through alternative binding mechanisms using fluoropolymer and co-binder materials.
Solution Approach 2:
The invention changes the physical and chemical parameters of the electrode formulation by replacing the solvent medium with a dry powder mixture containing fluoropolymer and co-binder. This parameter change enables the coating process to proceed without thermal evaporation, fundamentally altering the manufacturing energy requirements.
3Ease of manufacture
If solvent-based methods are used to prepare electrode formulations, then the coating process can be performed, but environmental impact worsens
Solution Approach 1:
The invention extracts and removes the solvent component from the electrode formulation, transitioning from a solvent-based slurry to a solvent-free dry mixture. This eliminates the need for energy-consuming evaporation ovens while maintaining the coating process through alternative binding mechanisms using fluoropolymer and co-binder materials.
Solution Approach 2:
The invention changes the physical and chemical parameters of the electrode formulation by replacing the solvent medium with a dry powder mixture containing fluoropolymer and co-binder. This parameter change enables the coating process to proceed without thermal evaporation, fundamentally altering the manufacturing energy requirements.
4Shape
If jet-milling is used for PTFE fibrillization, then fibrils are formed, but batch operation is required which is incompatible with continuous industrial operation
Solution Approach 1:
The invention replaces the batch-based jet-milling process with a continuous extrusion process that performs PTFE fibrillization continuously. The extruder maintains constant operation with continuous material feed and output, enabling uninterrupted production while achieving the same fibril formation effect through the extrusion die geometry and processing conditions.
Solution Approach 2:
The invention substitutes the high-speed impact mechanical system of jet-milling with the controlled shear and compression mechanics of extrusion through the die. This mechanical substitution achieves fibril formation through elongational flow and controlled deformation rather than high-velocity particle impact, enabling continuous operation.
5Shape
If jet-milling is used for PTFE fibrillization, then fibrils are formed, but fragile active material such as graphite is damaged
Solution Approach 1:
The invention substitutes the high-speed impact mechanical system of jet-milling with the controlled shear and compression mechanics of extrusion through the die. This mechanical substitution achieves fibril formation through elongational flow and controlled deformation rather than high-velocity particle impact, enabling continuous operation.
Solution Approach 2:
The invention modifies the mechanical stress parameters from high-impact random collisions in jet-milling to controlled shear and elongational flow in extrusion. This parameter change in the mechanical action profile achieves fibrillization at lower stress levels that do not damage fragile active materials like graphite.
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
This method enables the production of electrodes with controlled porosity and mechanical strength, suitable for lithium-ion batteries, reducing production costs and environmental impact while maintaining performance across multiple cycles.
Implementation Method 1
fibrillating the mixture obtained by extrusion
Implementation Method 2
fibrillating the mixture obtained by extrusion
Data Source
AI summary
The present application relates to fluoropolymer-based, solvent-free electrode formulations obtained by extrusion and/or comprising one or more co-binders including TPU, to electrodes containing the same and to corresponding electrochemical elements and storage cells.