Pouch Battery Venting Structure for Gas Release Without Electrolyte Leakage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing technologies for pouch-shaped secondary batteries do not effectively discharge high-pressure gas from the battery case while preventing deformation and electrolyte leakage.
Innovation Solution
A venting device with a lower vent portion, upper vent portion, wing portion, discharge portion, and shaft unit is inserted into the sealed portion of the battery case. The shaft unit includes an elastic portion that biases the shaft unit to seal the guide passage at normal pressure and open a gas flow channel at increased pressure, allowing only gas to be discharged.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If gas is collected in a separate gas pocket and the battery case is cut and thermally fused again, then gas can be removed from the battery cell, but the production process becomes complicated and cost increases
Solution Approach 1:
The invention extracts the gas removal function from the sealed portion itself by forming a gas ejection hole directly in the sealed portion. This allows gas to be ejected without needing to cut and re-seal the battery case, thereby simplifying the production process while maintaining effective gas removal capability
Solution Approach 2:
The gas ejection hole is formed in advance during the sealing process before the battery is assembled. This preliminary action eliminates the need for subsequent cutting and re-sealing operations, reducing production complexity while ensuring gas can be removed when needed
2Ease of manufacture
If gas is not efficiently removed from the battery cell, then the production process is simplified, but the battery case deforms and performance deteriorates
Solution Approach 1:
The gas ejection hole extracts the gas accumulation problem from the sealed portion, allowing gas to be vented directly without compromising the sealed structure. This maintains production simplicity while preventing battery deformation and performance degradation
Solution Approach 2:
The gas ejection hole acts as an intermediary channel that allows gas to escape from the sealed portion without breaking the seal. This mediator structure enables gas removal while maintaining the integrity and simplicity of the sealed portion
3Device complexity
If a venting device is not provided, then the battery structure is simpler, but the battery explodes when pressure exceeds a specific level
Solution Approach 1:
The sealed portion itself provides the venting function through the gas ejection hole, eliminating the need for separate venting devices. This self-service approach maintains structural simplicity while preventing explosion by allowing pressure relief
Solution Approach 2:
The venting function is extracted from the sealed portion by forming a dedicated gas ejection hole, separating the safety function from the structural integrity requirements. This allows the battery to remain simple in structure while incorporating essential safety features
4Strength
If the sealed portion is made more robust to prevent deformation, then battery integrity is improved, but gas cannot be efficiently discharged
Solution Approach 1:
The gas discharge function is extracted from the sealed portion by forming a dedicated gas ejection hole. This allows the sealed portion to maintain its strength and integrity while providing an efficient pathway for gas discharge through the hole
Solution Approach 2:
The sealed portion is segmented into the main sealed structure and the gas ejection hole. This segmentation allows the main structure to maintain strength for integrity while the hole provides efficient gas 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
The venting device simplifies the production process, reduces costs, and prevents battery deformation by efficiently discharging high-pressure gas while maintaining the integrity of the electrolyte solution.
Implementation Method 1
a shaft unit (210), and the elastic portion (220) is positioned around an outer surface of the shaft unit (210)
Implementation Method 2
a lower disk (211) located at a lower end of the shaft unit (210), and the lower disk (211) is configured to allow a gas component generated in the battery case (120) to pass through the lower disk (211) without allowing an electrolyte solution to pass through the lower disk (211)
Data Source
AI summary
A venting device for a secondary battery, such as a pouch-shaped secondary battery includes a lower vent portion positionable within a receiving portion of a battery case, an upper vent portion positionable outside of the battery case and communicating with a cavity of the lower vent portion, and a wing portion positionable along a sealed portion of the battery case and encircling an outer perimeter of the upper vent portion. The venting device includes a discharge portion communicating with the upper vent portion, in order to allow gas to pass from the upper vent portion through the discharge portion, and a shaft unit located in the cavity of the lower vent portion, wherein the shaft unit includes an elastic portion.