Porous Separator Coating for Safer High-Capacity Electrochemical Cells
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
As electrochemical devices with increasing capacity face higher risks of fire and explosion, there is a need for enhanced heat resistance and safety measures, particularly in applications like electric vehicles and energy storage devices.
Innovation Solution
The implementation of a porous separator with a core-shell structure coated with hydrophilic inorganic materials or polymers and an electrolyte containing a nitrile-based compound, which enhances wettability and ionic conductivity, thereby improving safety and performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the capacity of the electrochemical device is increased, then the energy storage capability is improved, but the risk of fire and explosion increases
Solution Approach 1:
A coating layer comprising a hydrophilic inorganic material or a hydrophilic polymer is formed on the separator to act as an intermediary substance. This coating layer improves wettability with the electrolyte containing a nitrile-based compound, enhancing ionic conductivity while maintaining safety. The coating layer serves as a mediator that allows high capacity operation without proportionally increasing fire risk by improving electrolyte distribution and ion transport efficiency.
Solution Approach 2:
The separator is modified by changing its surface properties through coating with hydrophilic materials. This parameter change (surface wettability) enables better electrolyte penetration and ion transport, allowing the device to achieve high capacity with improved safety margins by optimizing the electrolyte-separator interface.
2Reliability
If a coating layer is formed on the separator to improve wettability, then ionic conductivity is enhanced, but device complexity increases
Solution Approach 1:
The separator utilizes a porous structure with a coating layer that maintains porosity while improving wettability. The porous structure allows electrolyte penetration and ion transport, and the coating layer enhances these properties without blocking pores, achieving high ionic conductivity through optimized pore architecture rather than complex multi-layer structures.
Solution Approach 2:
The separator is constructed as a composite material combining a base separator material (polyolefin or other suitable material) with a coating layer of hydrophilic inorganic material or hydrophilic polymer. This composite structure achieves improved wettability and ionic conductivity by combining the advantages of different materials - the mechanical strength and thermal stability of the base material with the enhanced electrolyte affinity of the coating layer.
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 described configuration provides improved wettability and ionic conductivity, leading to enhanced fire stability and battery performance while maintaining high capacity and output.
Implementation Method 1
a coating shell including one or more of a hydrophilic inorganic material or a hydrophilic polymer is formed on at least one polyolefin strand
Implementation Method 2
configured to allow ions to pass between the positive electrode and the negative electrode
Implementation Method 3
a porous membrane including a core-shell structure
Data Source
AI summary
Electrochemical devices are disclosed for various applications such as secondary batteries. In an embodiment, an electrochemical device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The separator includes a porous membrane including a core-shell structure that includes formed on at least one polyolefin strand. The coating shell includes one or more of a hydrophilic inorganic material or a hydrophilic polymer. The electrolyte includes a nitrile-based compound. The electrochemical device exhibits high ionic conductivity by including the porous separator having wettability to the electrolyte.