Foldable Pouch Cell Stepped Case Structure Against Electrode Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing foldable and bendable battery cells face issues with electrode assembly misalignment, separation, and reduced energy density due to uncoated portions, leading to safety concerns and capacity loss.
Innovation Solution
A foldable pouch-shaped battery cell design featuring an uncoated portion at the electrode and a recessed stepped structure in the pouch case, with insulating members and protruding tabs to secure electrode assembly position and prevent separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a pouch-type battery cell is folded to fit into a limited space, then the space utilization is improved, but the bonding strength of the folded portion deteriorates due to repeated bending and external impacts
Solution Approach 1:
The battery cell is divided into multiple pouches that can be independently folded and arranged. Each pouch is a separate unit that can be folded along predetermined lines, allowing the battery to adapt to limited spaces while maintaining structural integrity through modular segmentation
Solution Approach 2:
Folded portions are pre-formed during the manufacturing process before final assembly. The pouches are folded along predetermined fold lines in advance, and adhesive layers are applied to predetermined bonding surfaces before the folding operation, ensuring bonding strength is established before the folded portion undergoes subsequent handling and installation
Solution Approach 3:
Adhesive layers are introduced as intermediary materials between the pouch surfaces that require bonding. The adhesive compensates for the weakened bonding strength caused by repeated bending and external impacts on the folded portions, providing enhanced mechanical strength and reliability to the folded areas
2Strength
If adhesive is applied to the entire surface of the pouch, then the bonding strength is improved, but the manufacturing complexity and cost increase
Solution Approach 1:
Adhesive layers are applied only to predetermined bonding surfaces rather than the entire pouch surface. This localized application focuses the adhesive only where bonding is required, maintaining sufficient bonding strength while reducing adhesive material consumption and simplifying the manufacturing process
Solution Approach 2:
Instead of applying adhesive to the entire surface (excessive action), adhesive is applied only to the specific predetermined bonding surfaces (partial action) where it is needed for folding and assembly, optimizing both bonding strength and manufacturing efficiency
Data Source
Figure 1(a)~2
Figure 3~4(b)
Figure 5~6
AI summary
The present invention relates to a pouch-shaped battery cell having an electrode assembly received in a pouch-shaped battery case, wherein the electrode assembly includes positive electrodes and negative electrodes, each of the positive electrodes and the negative electrodes having a structure in which the length of the electrode in an overall width direction is less than the length of the electrode in an overall length direction, each of the positive electrodes and the negative electrodes has an uncoated portion, which is a portion coated with no electrode mixture, formed parallel to outer peripheries of the electrode in the overall width direction or outer peripheries of the electrode in the overall length direction and a coated portion, which is coated with an electrode mixture, formed at the remaining portion of the electrode excluding the uncoated portion, and a stepped structure is formed at the part of the pouch-shaped battery case corresponding to the uncoated portion so as to be recessed inwards.