Unit Cell Separator Adhesion to Prevent Electrode Displacement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in preparing unit cells for secondary batteries is the displacement of electrodes during the stacking process, which can lead to damage and reduced efficiency due to the need for high heat and pressure in laminating processes, and the inefficiency of using adhesives that require low heat and pressure.
Innovation Solution
An apparatus and method involving the use of nozzles to apply adhesive to separator sheets, turning the sheets upside down to adhere to electrodes, and using nip rolls to secure the stacks, eliminating the need for laminating processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a laminating process with high heat and pressure is used to adhere electrodes and separators, then the adhesion strength is improved, but the electrode may be damaged and the process complexity increases
Solution Approach 1:
The patent changes the adhesion mechanism from thermal/pressure-based (laminating) to chemical-based (adhesive). The adhesive composition is specifically designed to bond electrodes and separators at ambient or low temperatures, eliminating the need for high heat and pressure that could damage the electrode structure.
Solution Approach 2:
The patent introduces an adhesive as an intermediary substance between the electrode and separator. This adhesive layer mediates the bonding process, providing strong adhesion without requiring direct high-temperature contact between the electrode and separator, thus preventing electrode damage while maintaining bond strength.
2Strength
If a laminating process with high heat and pressure is used, then the adhesion strength is improved, but the device complexity and manufacturing cost increase
Solution Approach 1:
The patent extracts the adhesion function from the laminating process. Instead of using a complex laminating machine that applies heat and pressure, the invention applies adhesive directly to the separator or electrode using simple coating methods, eliminating the need for specialized laminating equipment while maintaining bond strength.
Solution Approach 2:
The patent uses a disposable adhesive layer that provides the necessary bonding function without requiring expensive, complex laminating equipment. The adhesive serves as a simple, cost-effective alternative to capital-intensive laminating machinery.
3Ease of operation
If electrodes and separators are simply stacked without adhesion, then the process simplicity is improved, but the electrode displacement occurs during transfer
Solution Approach 1:
The patent applies adhesive to the separator or electrode in advance during the stacking process. This preliminary adhesion action ensures that the electrode and separator remain bonded during subsequent transfer and handling operations, preventing displacement while maintaining process simplicity compared to post-stacking lamination.
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
Prevents electrode displacement, reduces manufacturing costs, and simplifies the preparation process by eliminating the need for laminators, thus reducing the apparatus size and enhancing process efficiency.
Implementation Method 1
a first nozzle for applying an adhesive to at least a portion of one surface facing upward of the unwound lower separator sheet; a second nozzle for applying an adhesive to at least a portion of one surface facing upward of the unwound upper separator sheet
Data Source
AI summary
An apparatus for preparing a unit cell is provided. The apparatus includes a lower separator reel from which a lower separator sheet is unwound, a first nozzle configured to apply an adhesive to at least a portion of one surface facing upward of the unwound lower separator sheet, an upper separator reel from which an upper separator sheet is unwound, a second nozzle configured to apply an adhesive to at least a portion of one surface facing upward of the unwound upper separator sheet, and a first nip roll configured to turn opposite surfaces of the upper separator sheet upside down so that the one surface of the upper separator sheet to which the adhesive has been applied is directed downward and adheres to an upper surface of a first electrode stably placed on the one surface of the lower separator sheet.