Core-Sheath Battery Separator for Thermal Runaway Mitigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery separators do not effectively manage temperature fluctuations and mechanical stress, which can lead to short circuits and potential fires due to insufficient thermal management and mechanical integrity.
Innovation Solution
A battery separator is designed with a fiber structure having a core-sheath configuration, where the core contains a phase change material and the sheath is made of a polymer material, allowing for thermal regulation and mechanical compensation through phase changes and polymer strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional separator is used, then the battery structure is simple, but the separator cannot effectively manage temperature increases leading to short circuits and potential fires
Solution Approach 1:
The separator is constructed as a composite material system combining a polyolefin base layer with a phase change material layer. This composite structure enables the separator to provide both mechanical separation function and active thermal management through phase change heat absorption, resolving the contradiction between reliability improvement and structural complexity by integrating multiple functions into a layered composite architecture.
Solution Approach 2:
The invention utilizes phase change material that undergoes parameter changes (phase transitions) at specific temperature thresholds. When the battery temperature reaches the phase change point, the material transitions from solid to liquid state, absorbing excessive heat and stabilizing the temperature. This dynamic parameter change enables active thermal management without requiring complex external control systems.
2Temperature
If the separator does not include thermal management functionality, then the structure remains simple, but temperature increases cannot be effectively managed
Solution Approach 1:
The phase change material layer provides self-service thermal management by automatically absorbing heat through phase transition when temperature increases occur. The system does not require external power sources, control circuits, or active management mechanisms - the separator itself performs the thermal regulation function passively through its material properties, thereby achieving temperature control without proportionally increasing system complexity.
Solution Approach 2:
The invention directly applies phase transition phenomena to achieve temperature control. The phase change material is selected to have a transition temperature matching the battery's critical thermal threshold. When overheating occurs, the material undergoes solid-to-liquid phase transition, absorbing latent heat and maintaining the battery temperature below dangerous levels, thus achieving effective temperature management through fundamental physical principles.
3Reliability
If a phase change material is added to the separator, then thermal regulation is improved, but the separator structure becomes more complex
Solution Approach 1:
The separator is segmented into distinct functional layers: a polyolefin base layer providing mechanical strength and separation, and a phase change material layer providing thermal management. This segmentation allows each layer to optimize its specific function without compromising the other, achieving improved safety through specialized functional zones while maintaining manufacturability through a clear layered architecture.
Solution Approach 2:
The phase change material layer is nested onto the polyolefin base layer, creating a layered composite structure where the thermal management functionality is integrated within the separator's overall architecture. This nesting approach allows the phase change material to be contained and supported by the base layer, achieving enhanced safety functionality while maintaining a compact, integrated separator structure.
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 separator effectively manages temperature increases by absorbing and dissipating heat, reducing the risk of short circuits and maintaining mechanical integrity, thereby enhancing safety and performance of the battery.
Implementation Method 1
the core of the fiber includes a phase change material
Implementation Method 2
absorbing and dissipating heat, reducing the risk of short circuits
Data Source
AI summary
A battery is provided. The battery includes a first electrode, a second electrode spaced apart from the first electrode, and a separator including a fiber disposed between the first electrode and the second electrode, the fiber including a core and a sheath at least partially surrounding the core, wherein the core of the fiber includes a phase change material, and wherein the sheath of the fiber includes a polymer material.