Composite porous membrane material filled with boron nitride particles and its preparation method and application

Abstract

The invention discloses a nanocomposite multi-porous membrane material, which uses polyimide (PI) nanofiber non-woven fabric as a base material, and nano boron nitride particles are filled in the pores of the base material; the nano boron nitride Boron particles, whose diameter is between 50-100nm, accounts for 30-60% of the total weight of the nanocomposite multi-porous membrane material; the thickness of the PI nanofiber nonwoven fabric is between 9-38 μm, and the porosity is between 60-38 μm. Between 80%. The nanocomposite multi-porous membrane material provided by the invention is resistant to high temperature, heat shrinkage, high voltage and high current impact, and mechanical impact, and is suitable for use as a safe battery separator and a safe supercapacitor separator, and can be used to manufacture various high-capacity and high-voltage membranes. Power lithium battery or super capacitor. The invention also provides a preparation method of the nanocomposite porous membrane material and its application as a 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 porous membrane material containing BN nanoparticles, 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 power and other fields. ...