Alumina particle-filled composite multi-arc hole membrane material and preparation method and application thereof

Abstract

The invention discloses an alumina particle-filled composite multi-arc hole membrane material. With polyimide (PI) nanofiber nonwoven fabric as a base material, holes of the base material are filled with micro-nano Al2O3 particles; the diameters of the micro-nano Al2O3 particles are 50-800nm; and the micro-nano Al2O3 particles account for 20%-50% of total weight of the composite multi-arc hole membrane material. According to the micro-nano composite multi-arc hole membrane material, the porosity is 30%-60%; the surface mean pore size is 50-800nm; and the thicknesses are 10-40 microns. The micro-nano composite multi-arc hole membrane material disclosed by the invention has high-temperature resistance, heat shrinkage resistance, high-voltage and high-current shock resistance and mechanical impact resistance, and is suitable for manufacturing various high-capacity and high-power lithium batteries or super-capacitors as a safety battery diaphragm and a safety super-capacitor diaphragm. The invention further provides a preparation method of the nano composite multi-arc hole membrane material, and an application of the nano composite multi-arc hole membrane material as the battery diaphragm.

Description

technical field [0001] The invention belongs to the field of battery separators, and relates to a porous membrane material, in particular to a composite multi-porous membrane material containing aluminum oxide micro-nano particles, a preparation method thereof, and an application as a battery separator. Background technique [0002] As the power battery of new energy vehicles, lithium-ion batteries have been developed rapidly and will become an indispensable daily necessities for human beings. However, since the currently used lithium battery separator is a polyolefin porous membrane material with poor temperature resistance, at a higher temperature, or in the case of overcharging, overdischarging and mechanical damage, lithium-ion batteries are prone to smoke, Fire, even explosion and other hidden dangers that endanger the safety of users. Therefore, improving the safety of lithium-ion batteries is the key to promoting the application of lithium-ion batteries in automotive...

AI Technical Summary

Problems solved by technology

However, since this electrospun nanofiber separator is a non-woven fabric stacked by fibers, it has too high porosity and too large surface pore size, resulting in a low charge retention rate of the battery and frequent micro-short circuits. Especially when the thickness of the battery separator is low, such as below 30 microns, the probability of this situation is quite high