Battery Sealing Plate Geometry for Stable Gas Venting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing secondary batteries face challenges in ensuring stable operation of the degassing valve when internal pressure increases, leading to potential safety issues due to variations in operating pressure and thermal fatigue.
Innovation Solution
The configuration of the secondary battery includes specific ratios and dimensions for the sealing plate and gas discharge valve, along with heat-insulating grooves and strategic placement of electrode terminals and liquid injection holes, to ensure stable operation of the degassing valve by leveraging bending deformation and preventing thermal fatigue.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the sealing plate thickness is increased to improve strength, then the structural integrity is improved, but the bending deformation capability required for gas discharge valve operation deteriorates
Solution Approach 1:
The sealing plate is designed with non-uniform thickness distribution, being thinner at the center region where bending deformation is needed for gas discharge valve operation, and thicker at the peripheral regions where structural strength is required. This local quality variation allows the sealing plate to simultaneously achieve sufficient overall strength and localized bending capability.
Solution Approach 2:
The invention optimizes the thickness parameter of the sealing plate by establishing specific ratio relationships between the thickness and the dimensions of the sealing plate. By controlling the thickness parameter within certain ranges and establishing quantitative relationships with other geometric parameters, the sealing plate achieves both adequate strength and proper bending deformation characteristics for reliable gas discharge valve operation.
2Reliability
If the sealing plate aspect ratio (L2/L1) is increased to enhance bending deformation, then the gas discharge valve operation is improved, but the structural rigidity deteriorates
Solution Approach 1:
The invention establishes quantitative parameter relationships by defining specific ranges for the aspect ratio L2/L1 and its relationship with thickness T1. By controlling these geometric parameters within optimized ranges, the sealing plate achieves the right balance between bending deformation capability for gas discharge and sufficient rigidity for structural stability.
3Reliability
If the gas discharge valve size is increased to improve operability, then the valve operation reliability is improved, but the sealing plate deformation capability deteriorates
Solution Approach 1:
The invention optimizes the size parameters of the gas discharge valve by establishing quantitative relationships between the valve length L3 and the sealing plate dimensions. By controlling the ratio L3/L1 within specific ranges, the gas discharge valve achieves reliable operation while maintaining the sealing plate's ability to undergo necessary bending deformation.
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 configuration enhances the operational stability of the degassing valve, allowing it to discharge gas reliably at desired pressures while preventing thermal fatigue and ensuring the battery case maintains structural integrity.
Implementation Method 1
the rectangular sealing plate is bent and deformed in a convex shape toward the outside of the battery case
Implementation Method 2
heat insulating grooves and strategic placement of terminal and liquid injection holes to prevent thermal fatigue
Data Source
AI summary
According to the present disclosure, a secondary battery in which a gas discharge valve has excellent operational stability is provided. A battery case of the secondary battery disclosed herein includes a flat rectangular sealing plate, and a gas discharge valve provided in the sealing plate. In addition, in the secondary battery, a thickness T1 of the sealing plate, a length L1 of a short side of the sealing plate, a length L2 of a long side of the sealing plate, and a length L3 of the gas discharge valve in a short side direction satisfy expression (1) represented by T1/L1≤0.1, expression (2) represented by L2/L1≥6, and expression (3) represented by L3/L1≥0.4. As a result, when an internal pressure of the case rises to a desired pressure, the sealing plate is easily bent and deformed, so that the gas discharge valve can be stably operated by the bending deformation.