Battery Module Cover Venting for Thermal Runaway Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Battery modules are vulnerable to thermal chain reactions, leading to uncontrolled flame and gas discharge, which can cause explosions, fires, and rapid voltage drops, posing safety risks and operational hazards.
Innovation Solution
A battery module design featuring intersecting score lines in covers and a venting hole, with adhesive sheets to control internal gas discharge and block external gas entry, enhancing thermal stability and safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If multiple battery modules are connected in a battery pack, then energy storage capacity increases, but thermal chain reaction vulnerability increases
Solution Approach 1:
The battery module incorporates a cover structure divided into multiple layers (first cover and second cover) with score lines that create segmented regions. This segmentation allows controlled separation during thermal events, isolating the affected area and preventing thermal propagation to other modules while maintaining the overall battery pack's energy storage capacity.
Solution Approach 2:
The adhesive sheet positioned between the first and second covers acts as an intermediary element. During normal operation, it maintains structural integrity. During thermal runaway, it allows controlled separation along the score lines, mediating between the internal pressure buildup and the external environment, thereby preventing uncontrolled flame and gas discharge that could trigger chain reactions in adjacent modules.
2Object-generated harmful factors
If flame is discharged to the front side of the battery module, then gas venting occurs, but module terminal damage and electrical short risk increase
Solution Approach 1:
The cover structure features localized score lines positioned at specific locations and orientations. These score lines create predetermined weak points that guide the flame and gas discharge in specific directions away from critical components like module terminals. The local structural modification at the score line locations enables controlled venting while protecting electrical safety.
3Object-affected harmful factors
If the cover structure is made more robust to prevent thermal propagation, then safety improves, but gas and flame venting control becomes difficult
Solution Approach 1:
The cover structure transitions from a static robust design to a dynamic response system. The score lines create regions of controlled weakness that allow the cover to adapt its integrity based on internal pressure conditions. During normal operation, the cover maintains robustness for thermal protection. During thermal runaway, the score lines enable controlled separation, dynamically adjusting the structure to allow safe gas and flame venting while still preventing uncontrolled thermal propagation.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Disclosed is a battery module. The battery module includes a case having a space provided therein and including a top plate; a battery cell located inside the case; a first cover coupled to an upper surface of the top plate and having a first score line; and a second cover coupled to an upper surface of the first cover and having a second score line.