Polymer Composite Battery Membrane Thermal Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lithium-ion battery membranes face challenges in balancing mechanical strength and high-temperature resistance stability, with existing methods either compromising on cost or performance.
Innovation Solution
A polymer composite membrane is developed, comprising a porous base membrane with a heat-resistant fiber layer formed by electrostatic spinning using a combination of polyetherimide and modified polyvinylidene fluoride, which enhances both mechanical strength and high-temperature stability while maintaining ion conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the melt-spinning and cold-stretching method is used to prepare the membrane, then the mechanical strength and cost are improved, but the high-temperature resistance stability deteriorates
Solution Approach 1:
The patent uses a composite structure consisting of a polyolefin base membrane and a heat-resistant fiber layer. The base membrane provides mechanical strength and cost-effectiveness, while the heat-resistant fiber layer (made from polymers with melting points above 180°C) provides high-temperature stability. This composite approach allows both requirements to be satisfied simultaneously.
Solution Approach 2:
The membrane is divided into two functional layers: a base membrane layer for mechanical support and a heat-resistant fiber layer for thermal stability. This segmentation allows each layer to optimize its specific function without compromising the other.
2Temperature
If the thermally induced phase separation method is used to prepare the membrane, then the high-temperature resistance stability is improved, but the mechanical strength and cost deteriorate
Solution Approach 1:
The patent combines a polyolefin base membrane (providing mechanical strength) with a heat-resistant fiber layer (providing high-temperature stability). This composite structure avoids the mechanical strength deterioration associated with thermally induced phase separation methods while maintaining cost-effectiveness.
3Temperature
If a heat-resistant fiber layer is added to the membrane, then the high-temperature resistance stability is improved, but the device complexity increases
Solution Approach 1:
The heat-resistant fiber layer is designed with porous characteristics that allow electrolyte penetration and ion transport. This porous structure maintains the functional requirements of the battery membrane while providing the necessary heat resistance, avoiding excessive complexity.
Solution Approach 2:
The heat-resistant fiber layer serves multiple functions: providing thermal stability, maintaining porosity for ion transport, and ensuring mechanical integrity. This multi-functionality reduces the need for additional separate components, thereby limiting the increase in device complexity.
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 polymer composite membrane exhibits improved thermal shrinkage resistance, mechanical strength, and ion conductivity, ensuring safer and more efficient lithium-ion battery performance, particularly at high temperatures.
Implementation Method 1
a heat-resistant fiber layer which is formed by electrostatic spinning on a porous base membrane
Data Source
AI summary
The disclosure relates to the field of lithium-ion batteries, and discloses a polymer composite membrane and a method for preparing same. The disclosure further includes a lithium-ion battery for which the foregoing polymer composite membrane is used. The polymer composite membrane includes a porous base membrane and a heat-resistant fiber layer covering at least one side surface of the porous base membrane, where materials of the heat-resistant fiber layer contain a first polymeric material and a second polymeric material.