Battery Cell Packaging Film Grooves to Prevent Seal Wrinkling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The packaging of battery cells, particularly large ones, faces issues of uneven top sealing positions and wrinkling due to extrusion stress during the packaging process, which affects reliability.
Innovation Solution
A battery cell design featuring grooves on the packaging film to accommodate connection portions of the electrode assembly, reducing interference and extrusion stress between the packaging films, thereby improving packaging reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the battery cell uses a conventional packaging structure without grooves, then the packaging process is simple, but the packaging film becomes uneven and wrinkles due to extrusion stress during packaging
Solution Approach 1:
The patent introduces grooves at specific locations on the packaging film where the connection portion is located. These grooves create local structural differences that allow the packaging film to better accommodate the connection portion during extrusion, preventing wrinkles and unevenness at critical areas while maintaining simplicity elsewhere.
Solution Approach 2:
The grooves are pre-formed on the packaging film before the packaging process. This preliminary structural preparation ensures that when the connection portion is inserted and extrusion occurs, the packaging film already has the appropriate geometry to accommodate it, preventing deformation and wrinkles during the packaging process.
2Reliability
If the connection portion is accommodated without grooves, then the packaging structure is simple, but the connection portion interferes with the packaging film causing extrusion stress and wrinkling
Solution Approach 1:
The grooves are specifically positioned at the location where the connection portion will be accommodated. This localized structural modification creates a stress-relief zone that prevents the connection portion from interfering with the packaging film, eliminating extrusion stress and wrinkling at the critical area.
Solution Approach 2:
The grooves act as an intermediary structure between the connection portion and the packaging film. By providing this intermediate geometric feature, the connection portion can be accommodated without directly interfering with the packaging film, thus preventing harmful extrusion stress and wrinkling.
3Quantity of substance
If the battery cell maintains high energy density with compact size, then space utilization is efficient, but the packaging film is more prone to wrinkling due to higher extrusion stress
Solution Approach 1:
The grooves are strategically positioned at the connection portion area where extrusion stress concentrates. This localized structural feature provides stress relief precisely where needed, allowing the rest of the packaging to maintain compactness for high energy density while preventing wrinkles at the critical connection area.
Data Source
AI summary
A battery cell includes an electrode assembly, a packaging bag, and a first tab lead. The packaging bag includes a first packaging film and a second packaging film. An end of the first tab lead is connected to an end of the first tab of the electrode assembly to form a first connection portion, and another end of the first tab lead extends out of the packaging bag. A first groove and a second groove are formed on a side of the first packaging film facing the second packaging film; at least a portion of the body portion of the electrode assembly is accommodated in the first groove; and at least a portion of the first connection portion is accommodated in the second groove.