Battery Module Expansion Sheet for Thermal Runaway Venting
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Solution Overview
Problem
During thermal runaway in battery modules, the upward convex deformation of the upper cover creates a space that traps high-temperature gas, hindering smooth gas discharge and complicating fire extinguishment.
Innovation Solution
Incorporating an expansion sheet between the upper cover and the battery cell assembly that expands when heated, filling the space formed by the convex deformation and facilitating gas discharge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the upper cover is allowed to deform upward under heat, then the structural integrity is maintained, but a space is formed that traps high-temperature gas and hinders gas discharge
Solution Approach 1:
An expansion sheet is introduced as an intermediary component between the upper cover and the battery cell assembly. This sheet fills the space formed by upward deformation of the upper cover, preventing high-temperature gas from being trapped while allowing the cover to maintain its structural integrity during thermal events.
Solution Approach 2:
The expansion sheet undergoes parameter change through thermal expansion when exposed to heat. As the temperature increases, the sheet expands in volume to fill the space created by upper cover deformation, dynamically adapting to the thermal conditions and preventing gas entrapment.
2Temperature
If the upper cover deforms upward due to heat, then thermal expansion is accommodated, but gas discharge becomes difficult and fire extinguishment is complicated
Solution Approach 1:
The expansion sheet serves as a mediator that accommodates thermal expansion of the upper cover while simultaneously maintaining open pathways for gas discharge. By filling the deformation space, it prevents gas trapping and ensures smooth gas flow during thermal runaway events.
Solution Approach 2:
The expansion sheet automatically activates through heat-induced expansion, self-adjusting to fill the space created by upper cover deformation. This self-service mechanism eliminates the need for external control systems while ensuring continuous gas discharge efficiency during thermal events.
3Object-generated harmful factors
If an expansion sheet is added to fill the space, then gas discharge is improved, but device complexity increases
Solution Approach 1:
The expansion sheet is designed as a simple, cost-effective component that performs its function during thermal events. It is a single-use element that expands when needed and does not require complex mechanisms, control systems, or maintenance, thereby improving gas discharge without significantly increasing device complexity.
Solution Approach 2:
The expansion sheet utilizes inherent material properties that change with temperature, expanding automatically when heated. This passive parameter change mechanism eliminates the need for active control systems, motors, or sensors, achieving improved gas discharge with minimal added complexity.
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 expansion sheet effectively fills the space created by the convex deformation, ensuring smooth gas discharge and enhancing fire extinguishment by preventing gas entrapment.
Implementation Method 1
when a heat is applied to the expansion sheet and a temperature of the expansion sheet is higher than or equal to a predetermined temperature, the expansion sheet expands toward the top case
Data Source
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AI summary
A battery module (10) is disclosed. The battery module (10) includes a battery cell assembly (100) including a plurality of battery cells (110); a case assembly (200) accommodating the battery cell assembly (100), the case assembly (200) including a top case (221) positioned on the battery cell assembly (100); and a bus bar assembly (300) including a bus bar unit (310) configured to electrically connect the plurality of battery cells (110), a connection frame (320) connected to the bus bar unit (310) and positioned under the top case (221), and an expansion sheet (340) positioned between the connection frame (320) and the top case (221). When a heat is applied to the expansion sheet (340) and a temperature of the expansion sheet (340) is higher than or equal to a predetermined temperature, the expansion sheet (340) expands toward the top case (221).