Jelly-Roll Electrode Assembly Using PCM to Reduce Core Heat Gradient
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Solution Overview
Problem
The temperature difference between the center and outer shell of a jelly-roll type electrode assembly in secondary batteries leads to performance deterioration due to varying reaction rates.
Innovation Solution
Incorporating phase change materials at the winding center of the electrode stack to absorb heat and reduce temperature differences, using materials that change phase from solid to liquid at specific temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a jelly roll type electrode assembly is used for easy manufacturing and high energy density, then manufacturing ease and energy density are improved, but temperature difference between center and outer shell increases causing performance deterioration
Solution Approach 1:
The invention applies a cooling agent specifically to the winding center portion of the electrode assembly, creating a localized cooling system where different regions have different thermal properties. The cooling agent is disposed between the separator and the winding center, providing targeted thermal management to the hottest region without affecting the overall structure or manufacturing process.
2Use of energy by moving object
If heat is collected in the center of the cell during charging and discharging, then energy density is improved, but temperature difference increases causing performance deterioration
Solution Approach 1:
The invention converts the harmful heat accumulation in the winding center into a beneficial effect by using the cooling agent to absorb this heat through phase change. The heat generated during charging and discharging, which previously caused performance deterioration, is now utilized to drive the phase change of the cooling agent, which in turn absorbs excess heat and maintains temperature equilibrium, thereby converting a harmful thermal effect into a useful thermal management mechanism.
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 phase change materials effectively mitigate temperature differences, preventing battery performance degradation by maintaining temperature equilibrium, thereby enhancing battery performance and efficiency.
Implementation Method 1
the phase change material disposed at the winding center of the electrode stack may be changed in phase to absorb the heat of the winding center
Implementation Method 2
the temperature difference compensating member comprising the phase change material disposed at the winding center of the electrode stack may be changed in phase to absorb the heat of the winding center
Data Source
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AI summary
The present invention relates to an electrode assembly and a secondary battery comprising the same. The electrode assembly according to the present invention comprises an electrode stack, in which electrodes and a separator are alternately stacked to be wound and a temperature difference compensating member disposed at a winding center of the electrode stack to compensate so that a temperature difference between a winding outer shell and a winding center of the electrode stack is reduced, wherein the temperature difference compensating member comprises a phase change material.