Flexible Secondary Battery with Folded Sealing for Repeated Bending
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current secondary batteries used in wearable devices lack flexibility and high hermeticity, making them unsuitable for curved surfaces and repeated bending, which can lead to deterioration and leakage.
Innovation Solution
A secondary battery design featuring a novel structure with a flexible exterior body that includes multiple sealing portions and a unique folding mechanism, allowing for repeated bending while maintaining hermeticity and reducing stress on the exterior body.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a conventional rigid secondary battery structure is used, then hermeticity is maintained, but flexibility and ability to bend repeatedly are lost
Solution Approach 1:
The exterior body is constructed from a flexible laminate structure comprising multiple layers including a flexible resin layer and an aluminum foil layer. This flexible shell design allows the battery to bend repeatedly while maintaining hermeticity through the coordinated deformation of the laminate layers, resolving the contradiction between flexibility and hermetic sealing.
Solution Approach 2:
The battery structure incorporates dynamic elements including folded portions in the exterior body and electrode assemblies that can deform during bending. The folded portions allow the rigid sealing regions to remain stationary while other parts flex, enabling repeated bending without compromising the hermetic sealing integrity.
2Adaptability or versatility
If the battery structure is made flexible to allow bending, then adaptability to curved surfaces improves, but stress concentration and deterioration increase
Solution Approach 1:
The battery is divided into multiple functional segments including folded portions, sealing portions, and electrode assemblies. The folded portions act as hinge regions that concentrate bending stress away from the sealing portions and electrodes, allowing repeated bending while preventing deterioration in critical areas through strategic stress distribution.
Solution Approach 2:
The laminate exterior body structure provides inherent cushioning against mechanical stress through its multi-layer construction. The flexible resin layers and aluminum foil layers work together to absorb and distribute bending stresses before they reach the electrodes and sealing portions, preventing deterioration through pre-engineered stress mitigation.
3Reliability
If sealing portions are added to improve hermeticity, then reliability increases, but device complexity increases
Solution Approach 1:
The exterior body laminate serves multiple functions simultaneously: it provides structural support, ensures hermetic sealing, enables flexibility for bending, and protects internal components. The folded portions also serve dual purposes of stress management and sealing reinforcement, reducing overall structural complexity while maintaining high reliability.
Data Source
AI summary
A secondary battery with a novel structure that can be bent repeatedly is provided. In the secondary battery, an exterior body includes a front surface, a back surface, a first sealing portion, and a second sealing portion. The front surface includes a first long side, a second long side, a third side, and a fourth side. The third side and the fourth side face each other. The third side and the fourth side are substantially perpendicular to the first long side. The front surface includes a third sealing portion. The first sealing portion is along the third side. The second sealing portion is along the fourth side. The third sealing portion includes a region overlapping with the first sealing portion and a region overlapping with the second sealing portion. At least one of the first terminal and the second terminal overlaps with the first sealing portion.