Non-woven ceramic membrane with excellent closed-pore performance for lithium ion battery and technology

Abstract

The invention provides a non-woven ceramic membrane with excellent closed-pore performance for a lithium ion battery. The non-woven ceramic membrane comprises a non-woven base material and coatings with the closed-pore performance. The non-woven ceramic membrane is characterized in that the coatings with the closed-pore performance are uniformly coated on the two surfaces of the non-woven base material, the thickness of the non-woven ceramic membrane for the lithium ion battery is 30-50mu m, the porosity of the non-woven ceramic membrane is 40-60%, the average pore diameter of the non-woven ceramic membrane is 0.1-0.5mu m, the closed-pore temperature of the non-woven ceramic membrane is 120-130 DEG C, and the membrane rupture temperature of the non-woven ceramic membrane is 300-500 DEG C. The invention also provides a preparation technology of the non-woven ceramic membrane with the excellent closed-pore performance for the lithium ion battery. The non-woven ceramic membrane has the advantage that the disintegration or explosion of the battery is not easy cause; the adhesive power between the ceramic coating and the base material is increased, and no powder falls off the surface of the membrane under the conditions of bending, rubbing and the like; the consistency of the membrane thickness is substantially improved; and the non-woven ceramic membrane has good high temperature resistance performance, high ion penetrability, low resistance and stable electrochemical property.

Description

technical field

[0001] The invention relates to a non-woven ceramic diaphragm for lithium-ion batteries with excellent closed-pore performance and a preparation technology thereof, belonging to the technical field of lithium-ion batteries. Background technique

[0002] At present, lithium-ion battery separator materials are mainly polyolefin separators, such as single-layer polypropylene (PP) microporous membranes, single-layer polyethylene (PE) microporous membranes, and three-layer PP / PE / PP composite membranes. The melting point of the polyolefin separator is low: the closed cell temperature of the PE separator is 130-140°C, and that of the PP separator is 150-166°C. The separator is easy to shrink when heated, and the direct contact of the positive and negative electrodes will cause a short circuit of the lithium-ion battery, and it is easy to break at high temperature. film, causing disintegration or explosion of the lithium-ion battery.

[0003] Non-woven ceramic separ...