Folded Separator Battery Cell Layout for Gas Escape
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In battery cells where the separator is folded and extends between positive and negative electrodes, the folded portion can trap gas near the electrode ends, reducing battery capacity and posing a risk of ignition due to Li deposition and contaminant deposition from gas-generated metal.
Innovation Solution
A battery module design where the folded separator covers a portion of the second electrode on the same side, allowing gas to easily escape, and a method of manufacturing that involves wrapping electrodes and a separator with an exterior material and removing gas with the folded separator covering the upper portion of the second electrode.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the separator is folded and extends through between the positive electrode and the negative electrode, then the separator can effectively separate the electrodes, but gas generated from the electrode remains near the end of the electrode covered by the folded portion of the separator
Solution Approach 1:
The patent extracts the harmful gas from the confined space under the folded separator by providing a gas discharge port that allows gas to escape from the battery cell. This removes the gas accumulation problem while preserving the separator's folding structure for effective electrode separation.
Solution Approach 2:
The patent introduces an intermediary component (gas discharge port or communication hole) that mediates between the gas generation source (electrode) and the external environment, allowing controlled gas release without compromising the separator's function.
2Device complexity
If the folded portion of the separator covers the end of the electrode, then the separator structure is simplified, but contaminants such as metal pushed up by the gas would adhere to and deposit on the end of the electrode
Solution Approach 1:
The patent removes the harmful contaminants from the system by providing a gas discharge path that allows gas and suspended contaminants to escape together, preventing contaminant deposition on the electrode while maintaining the simple folded separator structure.
Solution Approach 2:
The patent converts the harmful gas pressure that pushes contaminants onto the electrode into a beneficial force that drives both gas and contaminants out through the gas discharge port, transforming a harmful effect into a useful gas removal mechanism.
3Volume of moving object
If gas remains near the electrode end covered by the separator, then the battery structure is compact, but the remaining gas may inhibit a reaction in the battery between the positive electrode and the negative electrode
Solution Approach 1:
The patent extracts the gas that would otherwise inhibit battery reactions by providing a dedicated gas discharge port. This maintains the compact battery structure while removing the gas that blocks electrode reactions, thereby preserving both compactness and reaction efficiency.
Data Source
AI summary
A positive electrode (110) is a first electrode, and a negative electrode (120) is a second electrode having an area larger than that of the first electrode. A separator (130) is folded and extends through between the positive electrode (110) and the negative electrode (120) adjacent to each other. A folded portion of the separator (130) covers a portion of the negative electrode (120) on the same side in each of a plurality of battery cells (10). Specifically, the folded portion of the separator (130) covers the upper portion of the negative electrode (120) in each of the plurality of battery cells (10).