Battery Cell Cover Sealing for Controlled Vent Gas Release
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery systems face challenges in securely managing thermal runaway, as venting gas streams from a failing battery cell can lead to thermal propagation and potential runaway in adjacent cells, due to inadequate sealing and adhesion of cover elements.
Innovation Solution
A cover element made of a mica sheet, sealed to battery cells with an adhesive extending around venting exits, provides secure sealing and ruptures at predetermined points to contain venting gas streams, preventing thermal propagation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a cover element is used to protect battery cells from venting gas streams, then thermal propagation is prevented, but the cover element may lift off from battery cells due to gas pressure
Solution Approach 1:
The adhesive arrangement is segmented into multiple separate adhesive strips positioned at different locations on the battery cell, rather than using a single continuous adhesive layer. This segmentation allows the cover element to remain securely attached at multiple points while accommodating pressure differential forces during thermal runaway events
Solution Approach 2:
The adhesive strips are strategically positioned at specific locations on the battery cell where they provide optimal attachment while allowing the cover element to rupture or vent at controlled points. The local adhesive placement creates different functional zones on the cover element - secured areas for attachment and vulnerable areas for controlled rupture
2Ease of manufacture
If adhesive strips span multiple battery cells, then manufacturing is simplified, but venting gas can flow between cells through the adhesive
Solution Approach 1:
The continuous adhesive strip is divided into separate discrete adhesive strips, each positioned on individual battery cells or at specific intervals. This segmentation prevents the formation of continuous pathways that could allow venting gas to flow between adjacent battery cells, while still providing adequate attachment across the entire cover element
Solution Approach 2:
The harmful continuous adhesive pathway is extracted and replaced with discrete segmented adhesive strips. This removal of the continuous connection eliminates the thermal propagation risk while maintaining the beneficial attachment function
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 solution effectively prevents thermal runaway in adjacent cells by ensuring the cover element remains adhered and ruptures at designed points, diverting gas streams away from adjacent cells, thus enhancing safety.
Implementation Method 1
The cover element is directly sealed to the venting side of each battery cell by an adhesive extending around each of the venting exits
Implementation Method 2
the cover element is adapted to rupture at sections opposite the venting exits by the pressure of the discharged venting gas stream
Data Source
Figure 1
Figure 2
AI summary
The present disclosure refers to a battery system (100) including a plurality of battery cells (12), wherein each of the battery cells (12) includes a venting side with a venting exit (14) for discharging a venting gas stream (V), a cover element (20) covering one or more of the plurality of battery cells (12) at the venting sides to protect the battery cells (12) from the venting gas stream (V), wherein the cover element (20) is directly sealed to the venting side of each battery cell (12) by an adhesive (16) extending around each of the venting exits (14).