Electrolytic Capacitor Cathode Lead Frame Bending Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrolytic capacitors face a trade-off between increasing the exposed terminal area and maintaining a sufficient contact area between the cathode lead frame and the cathode part, which affects resistance and mounting strength.
Innovation Solution
The design includes a cathode lead frame with a cathode mount and terminal that bends at specific boundaries, featuring projections to enhance the exposed area while ensuring a sufficient contact area, and a smaller dimension in the second direction to facilitate bending and minimize volume, thereby improving capacitance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If the exposed terminal area is increased, then the mounting strength and electrical connection are improved, but the contact area between the cathode lead frame and the cathode part is reduced
Solution Approach 1:
The cathode lead frame is designed with a bent configuration that utilizes three-dimensional space. The lead frame extends in multiple directions with specific bending angles, allowing the terminal portion to be positioned in a different spatial plane from the cathode part contact portion. This dimensional arrangement enables both the exposed terminal area and the contact area to be sufficiently large without interfering with each other, as they occupy different spatial dimensions.
Solution Approach 2:
The cathode lead frame is divided into distinct functional segments: a first portion that contacts the cathode part, a second portion that forms the exposed terminal, and intermediate connecting portions with specific bending angles. This segmentation allows each portion to be optimized independently - the contact portion maximizes contact area with the cathode part, while the terminal portion maximizes exposed area for mounting, resolving the area trade-off through functional separation.
2Reliability
If the cathode lead frame is designed with larger dimensions to ensure sufficient contact area, then the contact reliability is improved, but the overall volume of the capacitor increases
Solution Approach 1:
Instead of increasing the planar dimensions of the cathode lead frame to improve contact reliability, the design utilizes vertical dimension through bending. The lead frame is configured with bending angles of 45° to 135° relative to the capacitor element, allowing the terminal to extend upward or sideways in three-dimensional space. This enables sufficient contact area at the base while keeping the overall volume compact, as the terminal exposure occurs in a different dimensional plane.
Solution Approach 2:
The cathode lead frame is designed as a thin, flexible metallic structure that can be bent into complex configurations without requiring large volume. The thin-film nature of the lead frame allows it to achieve sufficient contact area through strategic bending and positioning rather than through large planar dimensions, thereby maintaining compact capacitor volume while ensuring reliable electrical contact.
Data Source
AI summary
A solid electrolytic capacitor includes a capacitor element, an anode lead frame, a cathode lead frame, and an exterior member. The capacitor element includes an anode part and a cathode part. The cathode lead frame includes a cathode mount, a cathode connection part connected to the cathode mount, and a cathode terminal connected to the cathode connection part. The cathode lead frame bends in one direction at a first boundary between the cathode mount and the cathode connection part, and further bends in another direction at a second boundary between the cathode connection part and the cathode terminal. At least one of the cathode mount and the cathode terminal has a projection at an edge of the at least one of the cathode mount and the cathode terminal. The edge is at a side close to the cathode connection part. The projection projects in a first direction along which the anode part and the cathode part are aligned.