Top Cap Assembly Heat Resistant Member for Battery Safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In cylindrical type secondary batteries, the gasket surrounding the current interrupt device (CID) short-circuiting member can melt and deform during external short-circuiting, leading to contact with the safety vent, which prevents the CID from interrupting electric current, potentially causing explosions.
Innovation Solution
A heat resistant member, made of materials like poly tetra fluoro ethylene or polyamide, is placed between the gasket and the safety vent to prevent heat transfer and direct contact, ensuring the CID and safety vent do not come into contact even when the gasket is molten.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a gasket surrounds the CID short-circuiting member for sealing, then sealing performance is improved, but the gasket may melt and deform at high temperature during external short-circuiting, causing contact between the CID and safety vent
Solution Approach 1:
A heat-resistant member is introduced as an intermediary component between the gasket and the safety vent. This mediator prevents direct heat transfer from the gasket to the safety vent during thermal events, while still allowing the gasket to perform its sealing function around the CID short-circuiting member.
Solution Approach 2:
The heat-resistant member is pre-installed on the safety vent before assembly, creating a protective barrier in advance. This prior cushioning ensures that when high temperature occurs during external short-circuiting, the safety vent is already protected from heat damage that would cause deformation and contact with the CID.
2Device complexity
If the safety vent is connected directly to the CID short-circuiting member for compact design, then device complexity is reduced, but contact between the CID and safety vent prevents current interruption during short-circuiting
Solution Approach 1:
The heat-resistant member serves as a physical spacer and mediator between the safety vent and CID short-circuiting member. It maintains the necessary separation distance to prevent contact during thermal deformation, while still allowing the compact connected design to be maintained for structural simplicity.
3Ease of manufacture
If the gasket is made of standard materials for ease of manufacture, then manufacturing cost is reduced, but the gasket lacks heat resistance and deforms during external short-circuiting
Solution Approach 1:
The sealing and thermal protection functions are segmented into two separate components: the standard gasket for sealing and ease of manufacture, and the heat-resistant member for thermal protection. This segmentation allows each component to be optimized independently - the gasket remains simple to manufacture while the heat-resistant member provides the necessary thermal barrier.
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 design enhances the safety of secondary batteries by preventing contact between the CID and safety vent during external short-circuiting, reducing the risk of explosion and improving overall safety compared to previous designs.
Implementation Method 1
a heat resistant member preventing heat transfer between the gasket and the safety vent
Data Source
AI summary
Provided is a top cap assembly for a cylindrical type secondary battery, including a CID short-circuiting member, which interrupts an electric current when a high voltage is generated in the cylindrical type secondary battery, a safety vent connected to an upper part of the CID short-circuiting member and including a plurality of notches, which are broken when a voltage equal to or greater than an allowable voltage of the CID short-circuiting member is generated, to discharge gas from the cylindrical type secondary battery, a top cap connected to the safety vent and disposed on the uppermost end of an upper opening part of the cylindrical type secondary battery, a gasket surrounding and sealing an outer circumferential surface of the CID short-circuiting member, and a heat resistant member preventing heat transfer between the gasket and the safety vent.