Solid Electrolytic Capacitor with Liquid Polymer Surrounding

Solution Overview

Problem

Conventional solid electrolytic capacitors face challenges in maintaining high breakdown strength, low leakage current, and long lifetime due to oxide film defects and temperature variations, especially when used under severe conditions.

Innovation Solution

A solid electrolytic capacitor design that incorporates a water-soluble high-molecular weight compound in a liquid form, with a specific volume ratio, surrounding the conductive high-molecular weight compound in a fine particle form, to efficiently repair oxide film defects and maintain dielectric integrity, while minimizing equivalent series resistance and moisture scattering.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a water-soluble high-molecular weight compound in solid or viscous form is used, then the oxide film can be repaired, but the moisture retention ability is insufficient and moisture scatters over time

Engineering Contradiction:

Improveoxide film repair capabilityVSAvoidmoisture retention duration

Core Design Contradiction:

ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The patent changes the physical state parameter of the water-soluble high-molecular weight compound from solid/viscous form to liquid form. This parameter change enables the compound to retain moisture more effectively while maintaining its oxide film repair capability, thus resolving the contradiction between repair capability and moisture retention duration.

Inventive Principle:

Principle #35Parameter changes

2Stability of the object's composition

If the water-soluble high-molecular weight compound is in solid form, then the structure is stable, but the oxide film defect repair efficiency is low

Engineering Contradiction:

Improvestructural stabilityVSAvoiddefect repair efficiency

Core Design Contradiction:

Stability of the object's compositionVSProductivity

Solution Approach 1:

The patent changes the physical state parameter of the water-soluble high-molecular weight compound from solid/viscous form to liquid form. This parameter change enables the compound to retain moisture more effectively while maintaining its oxide film repair capability, thus resolving the contradiction between repair capability and moisture retention duration.

Inventive Principle:

Principle #35Parameter changes

3Ease of operation

If a conventional solid electrolyte is used, then the capacitor can operate, but the lifetime is limited under severe conditions

Engineering Contradiction:

Improveoperational capabilityVSAvoidlifetime under severe conditions

Core Design Contradiction:

Ease of operationVSDuration of action of stationary object

Solution Approach 1:

The patent changes the physical state parameter of the water-soluble high-molecular weight compound from solid/viscous form to liquid form. This parameter change enables the compound to retain moisture more effectively while maintaining its oxide film repair capability, thus resolving the contradiction between repair capability and moisture retention duration.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite structure where liquid water-soluble high-molecular weight compound surrounds solid electrolyte fine particles. This composite arrangement allows both components to coexist with optimized volume ratios, enabling the system to achieve both good conductivity (from solid electrolyte) and effective oxide film repair (from liquid compound with moisture retention).

Inventive Principle:

Principle #40Composite materials

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 proposed design enhances the capacitor's lifetime, breakdown strength, and low temperature resistance properties by ensuring efficient defect repair and reduced equivalent series resistance, maintaining effective oxide film action over time.

Implementation Method 1

the water-soluble high-molecular weight compound has an oxide film repairing property

Methodology Applied

Scientific EffectOxide film repair: Chemical Bonding

Implementation Method 2

use moisture which the water-soluble high-molecular weight compound retains to repair the above-mentioned defective portion

Methodology Applied

Scientific EffectMoisture retention: Absorption (physical)

Data Source

PatentUS9978527B2Solid Electrolytic capacitor and manufacturing method thereof

Publication Date: 2018.05.22 RUBYCON CORPORATION

AI summary

A solid electrolytic capacitor includes: an anode foil on which an oxide film is formed; a cathode foil; and a separator between the anode and cathode foils, wherein a solid electrolyte in a fine particle form made of a conductive high molecular weight compound and a water-soluble high-molecular weight compound in a liquid form are introduced into a gap between the anode and cathode foils in a state where the water-soluble high-molecular weight compound in a liquid form surrounds the solid electrolyte, and a ratio of an area that the solid electrolyte occupies in the gap is set to a value which falls within a range of 1 vol % to 30 vol %, and a ratio of an area that the water-soluble high-molecular weight compound in a liquid form occupies in the gap is set to a value which falls within a range of 10 vol % to 99 vol %.