Conductive Polymer Solid Electrolytic Capacitor Low-Temperature Polymerization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for forming conductive polymer layers in solid electrolytic capacitors are time-consuming and not cost-effective due to the sequential application of monomer and oxidative polymerization catalyst solutions, which can lead to premature polymerization and degradation of the polymer layer.
Innovation Solution
A method involving the polymerization of a monomer in the presence of less than stoichiometric amounts of oxidative polymerization catalyst, along with a dopant, in a single polymerization solution, to form a conductive polymer layer that penetrates more intimately into the anode, reducing processing steps and improving capacitor performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sequential application of monomer and catalyst solutions is used, then polymer layer formation is achieved, but processing time increases and cost effectiveness decreases
Solution Approach 1:
The patent combines the monomer and oxidative polymerization catalyst into a single polymerization solution, eliminating the need for sequential application of separate solutions. This merging of components into one solution reduces processing steps and time while maintaining the polymer layer formation capability.
2Reliability
If stoichiometric amount of oxidative polymerization catalyst is used, then complete polymerization occurs, but premature polymerization in solution degrades the polymer layer
Solution Approach 1:
The patent uses less than a stoichiometric amount of oxidative polymerization catalyst per mole of monomer in the polymerization solution. This partial action prevents complete polymerization in the solution, avoiding premature polymerization and degradation, while still achieving sufficient polymerization on the anode surface to form a high-quality conductive polymer layer.
3Productivity
If single polymerization solution with less than stoichiometric catalyst is used, then processing efficiency improves, but polymerization control becomes more difficult
Solution Approach 1:
The patent changes the catalyst-to-monomer ratio parameter to less than stoichiometric amounts and controls the polymerization process by adjusting solution composition, application conditions, and polymerization kinetics. This parameter optimization enables efficient single-step processing while maintaining precise control over polymer layer formation and quality.
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 approach results in a solid electrolytic capacitor with decreased equivalent series resistance (ESR), especially at high humidity and high temperatures, and improved electrical performance by forming a more intimate conductive polymer layer with the anode.
Implementation Method 1
forming a conductive polymer coating over the anodized anode by polymerizing a monomer in the presence of an oxidative polymerization catalyst
Implementation Method 2
anodizing a surface of the anode to form a dielectric layer
Data Source
AI summary
A method for forming an electrolytic capacitor is disclosed. The method includes forming a conductive polymer coating over the dielectric layer by polymerizing a monomer in the presence of an oxidative polymerization catalyst. The conductive polymer coating is formed by dipping the anode in a polymerization solution comprising the monomer, the oxidative polymerization catalyst, and a polar solvent. The polymerization solution has a temperature of less than about 20° C. Cooling the polymerization solution further stabilizes the polymerization solution and prevents premature polymerization of the monomer(s). Thus, the resulting conductive polymer layer can be more intimately positioned with respect to the anode. As a result, the formed capacitor can exhibit better performance.