Sealed Battery Current Cut-Off Valve Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sealed batteries with current cut-off valves experience increased internal resistance due to the metal foil used for current conduction, which is undesirable for high-power applications like vehicles.
Innovation Solution
A sealed battery design featuring a current cut-off mechanism where the current cut-off valve is joined to a connecting member via a peripheral edge or surface connection, eliminating the need for additional conductive foils and maintaining high conductivity while allowing for reliable current cutoff during abnormal pressure conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a metal foil is used to conduct current from the electrode body to the external terminal, then the current cut-off valve can be connected to the electrode body, but the internal resistance of the battery increases
Solution Approach 1:
The invention extracts and removes the metal foil from the current conduction path. Instead of using a metal foil to connect the current cut-off valve to the electrode body, the patent directly connects the current cut-off valve to the electrode body through the case, eliminating the additional resistance introduced by the metal foil while maintaining the current cut-off function.
Solution Approach 2:
The invention merges the current conduction function with the case structure. The case itself serves as part of the current conduction path, integrating the structural support function with the electrical conduction function, thereby eliminating the need for separate metal foil components that would increase internal resistance.
2Device complexity
If the current cut-off valve is connected to the electrode body via metal foil, then the battery structure is simpler, but the battery cannot discharge large currents efficiently
Solution Approach 1:
The invention merges the current conduction function with the case structure. The case itself serves as part of the current conduction path, integrating the structural support function with the electrical conduction function, thereby eliminating the need for separate metal foil components that would increase internal resistance.
Solution Approach 2:
The case serves multiple functions: it provides structural support, contains the electrolyte and electrode body, and simultaneously acts as a current conduction path. This multi-functionality eliminates the need for additional metal foil components, simplifying the structure while maintaining high current discharge capability.
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 enables the battery to discharge large currents without increasing internal resistance, making it suitable for high-capacity applications like electric and hybrid vehicles by ensuring a larger conduction surface area and reliable current cutoff.
Implementation Method 1
when an internal pressure in the case rises above a predetermined level (when the internal pressure rises abnormally), the current cut-off valve is deformed
Implementation Method 2
the current cut-off valve is deformed when an internal pressure in the case rises above a predetermined level
Implementation Method 3
the current cut-off valve is conductively connected to the connecting member by joining linearly to a peripheral edge of an engagement hole
Data Source
AI summary
A sealed battery (10) provided by the present invention includes: a current cut-off valve (22); and a connecting member (30) having an engagement hole (34) formed in a location adjacent to the current cut-off valve. The current cut-off valve is conductively connected to the connecting member by joining linearly to a peripheral edge of the engagement hole and/or joining at a surface that is in contact with an inner wall of the engagement hole in a state in which part of the current cut-off valve is fitted into the engagement hole. When an internal pressure of a battery case (40) rises above a predetermined level, the current cut-off valve is deformed outward of the case by the internal pressure, the current cut-off valve is separated from the connecting member, and the electric connection between the connecting member and the current cut-off valve is broken.