Metal Oxide Ultrafine Fiber Separator Heat Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lithium ion secondary battery separators lack sufficient heat resistance and ionic conductivity, leading to poor performance in high energy density and high capacity batteries due to heat shrinkage and restricted ion movement.
Innovation Solution
A ultrafine fiber-based composite separator is developed using electrospun metal oxide/polymer composite fibers with a polymer resin coating, providing a fibrous porous body with continuous, randomly arranged fibers that maintain structural integrity and ionic conductivity at elevated temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a polyolefin separator is used, then it provides basic separation function, but it exhibits high heat shrinkage rate and poor heat resistance
Solution Approach 1:
The patent applies composite materials by combining metal oxide ultrafine fibers (providing heat resistance) with polymer fibers (providing mechanical strength and porosity). This creates a composite separator that maintains structural stability at high temperatures while preventing heat shrinkage, directly resolving the contradiction between heat resistance and dimensional stability.
2Reliability
If polyolefin separator porosity is increased to improve ionic conductivity, then charge-discharge properties improve, but mechanical strength decreases
Solution Approach 1:
The composite structure combines metal oxide ultrafine fibers (providing heat resistance and structural stability) with polymer fibers (providing mechanical strength). This allows the separator to maintain high porosity (30-80%) for good ionic conductivity while the composite framework preserves sufficient mechanical strength.
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 ultrafine fiber-based separator exhibits a low heat shrinkage rate, superior heat resistance, and enhanced ionic conductivity, improving cycle and power properties in secondary batteries, enabling the manufacture of high energy density and high capacity batteries.
Implementation Method 1
obtained by electrospinning a metal oxide precursor sol-gel solution or a mixture of a metal oxide precursor sol-gel solution and a polymer resin solution
Implementation Method 2
electrospinning a metal oxide precursor sol-gel solution
Data Source
AI summary
An ultrafine fiber-based composite separator comprising a fibrous porous body which comprises ultrafine metal oxide/polymer composite fibers, or ultrafine metal oxide fibers and a polymer resin coating layer formed on the surface thereof, the ultrafine fibers being continuously randomly arranged and layered, and obtained by electrospinning a metal oxide precursor sol-gel solution or a mixture of a metal oxide precursor sol-gel solution and a polymer resin solution, wherein the surface of the metal oxide/polymer composite fibers has a uniform mixing composition of the metal oxide and the polymer resin, in which the separator has a heat shrinkage rate at 150˜250° C. of 10% or less and does not break down due to melting at a temperature of 200° C. or lower, has low heat shrinkage rate, and superior heat resistance and ionic conductivity, being capable of providing improved cycle and power properties when used in manufacturing a battery.