Electrolytic Capacitor Electrolyte Structure for Long-Term ESR Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrolytic capacitors experience a significant increase in equivalent series resistance (ESR) over time, which degrades the conductive polymer and affects their performance.
Innovation Solution
Incorporating a non-aqueous solvent-based electrolyte layer with conductive particles, maintaining a D/T ratio of 0.01 to 0.9, where D is the average maximum diameter of the conductive particles and T is the average thickness of the separator, to suppress ESR increase.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conductive polymer is used as the solid electrolyte layer, then the capacitance is increased and ESR is reduced, but the ESR increases significantly over time due to degradation of the conductive polymer
Solution Approach 1:
The patent uses a composite electrolyte layer combining conductive polymer particles (for low ESR) with non-conductive polymer matrix (for stability). This composite structure allows the conductive particles to provide low resistance pathways while the stable polymer matrix prevents degradation, resolving the contradiction between initial low ESR and long-term ESR stability.
Solution Approach 2:
The patent changes the physical and chemical parameters of the electrolyte layer by controlling particle size distribution, polymer composition ratios, and cross-linking density. These parameter changes optimize both the initial ESR performance and long-term stability, allowing the capacitor to maintain reliable performance throughout its service life.
2Reliability
If the separator thickness is increased to prevent short circuit, then the safety is improved, but the capacitance decreases due to reduced active area
Solution Approach 1:
The patent employs a porous separator structure that provides high electrical insulation while maintaining thin thickness. The porous structure creates tortuous paths for electrical breakdown while allowing ionic transport, enabling the separator to be thin enough to preserve capacitance yet sufficiently insulating to prevent short circuits.
Solution Approach 2:
The patent applies different properties to different regions of the separator, with enhanced insulation characteristics at critical interfaces and optimized porosity in the bulk. This local quality differentiation allows the separator to provide maximum protection against short circuits while minimizing the impact on capacitance.
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 electrolytic capacitor maintains low ESR over a long period, preventing degradation and ensuring consistent performance.
Implementation Method 1
the electrolyte layer includes a non-aqueous solvent and conductive particles
Data Source
AI summary
A disclosed electrolytic capacitor includes a capacitor element. The capacitor element includes an anode body, a dielectric layer formed on a surface of the anode body, a cathode body, and an electrolyte layer and a separator that are disposed between the dielectric layer and the cathode body. The electrolyte layer includes a non-aqueous solvent and conductive particles. A ratio D/T of an average maximum diameter D of the conductive particles to an average thickness T of the separator is in a range of 0.01 to 0.9.