Vacuum Backfilling Hydrophobic Separator Impregnation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for filling porous, hydrophobic separator materials with polar electrolytes in high-voltage electrolytic capacitors, such as those used in implantable medical devices, are inefficient due to the hydrophobic nature of materials like fluorinated coatings, which resist wetting and require surfactants or surface modifications.
Innovation Solution
A method involving vacuum backfilling of capacitor assemblies, where the interior is evacuated and then filled with liquid electrolyte under pressure through a fill-port, allowing the electrolyte to penetrate porous, hydrophobic separators without the need for surfactants or surface energy modifications, using materials like PTFE and polypropylene as-is.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If hydrophobic separator materials (e.g., fluorinated materials) are used, then chemical inertness and structural stability are improved, but wetting by polar electrolyte deteriorates
Solution Approach 1:
The patent changes the physical state and pressure parameters of the electrolyte introduction process. By introducing electrolyte under pressure into a vacuum-evacuated capacitor assembly, the patent overcomes the hydrophobic surface energy barrier of fluorinated separator materials, enabling complete pore penetration without modifying the separator's chemical composition or surface properties.
2Reliability
If surfactants or surface energy modifications are used to improve wetting, then electrolyte penetration is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The patent extracts and eliminates the need for surfactants and surface energy modification steps from the manufacturing process. By using pressure differential (vacuum backfilling), the method achieves complete electrolyte penetration of hydrophobic separators without any chemical additives or surface treatments, thereby simplifying the manufacturing process and reducing costs.
Solution Approach 2:
The patent applies pneumatic principles by using vacuum evacuation and pressure differential to drive electrolyte penetration. The vacuum backfilling process uses pressure differentials to force the electrolyte through the hydrophobic separator pores, eliminating the need for surfactant-based wetting mechanisms.
3Ease of manufacture
If traditional filling methods are used, then assembly simplicity is maintained, but electrolyte impregnation of hydrophobic separators is insufficient
Solution Approach 1:
The patent performs preliminary vacuum evacuation of the capacitor assembly before electrolyte introduction. This preliminary action removes air and vapor from the separator pores, creating a vacuum that enhances subsequent electrolyte penetration when pressure is applied, ensuring complete impregnation of hydrophobic materials.
Solution Approach 2:
The patent employs pneumatic principles through vacuum backfilling, where vacuum evacuation followed by pressure-driven electrolyte introduction ensures complete pore penetration of hydrophobic separators, achieving reliable impregnation while maintaining manufacturing simplicity.
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 effectively impregnates hydrophobic separators with polar electrolytes, simplifying capacitor assembly, reducing costs, and enhancing the performance of capacitors used in medical devices by eliminating the need for surfactants and surface modifications, while maintaining structural integrity and preventing short-circuiting.
Implementation Method 1
using vacuum to evacuate the interior atmosphere of the capacitor assembly
Implementation Method 2
pressure may be applied to the reservoir of liquid electrolyte, forcing the liquid electrolyte into the evacuated capacitor assembly through the fill-port
Implementation Method 3
The fill-port can then be sealed. The present invention relates to a method of backfilling a capacitor assembly according to claim 1
Data Source
Figure 1
AI summary
Methods are provided to suitably impregnate low surface energy separator materials with polar electrolyte in an electrolytic capacitor. Backfilling methods overcome the high contact angles exhibited by polar electrolytes on porous hydrophobic separators, forcing the electrolyte into the separator pores, thereby sufficiently impregnating the separator disposed between two electrodes within the capacitor assembly. Methods enable use of separators sans surfactant or surface modifications to improve wetting.