Coating slurry for diaphragm, composite heat resisting diaphragm and preparation method of composite heat resisting diaphragm

Abstract

The invention provides coating slurry for a diaphragm, a composite heat resisting diaphragm, and a preparation method of the composite heat resisting diaphragm, wherein the coating slurry for the diaphragm comprises and is prepared from the following materials: organic particles, ceramic particles, a binder and water; by solid content, the organic particles account for 24.5%-99.5% by weight, the ceramic particles account for 0-75% by weight, and the binder accounts for 0.5%-15%; the solid content is 20%-50% of the total weight of the coating slurry. Compared with a diaphragm in the prior art, the closed pore temperature in an electrolyte / battery is lower, and a current is cut off before the accelerated heat release of the battery.

Description

technical field [0001] The invention belongs to the field of electrochemistry, and in particular relates to a coating slurry for a diaphragm, a composite heat-resistant diaphragm and a preparation method thereof. Background technique [0002] Lithium-ion batteries, as a clean energy source, have been widely used in civil and power fields. Especially in the application of electric vehicles, there has been a blowout growth in recent years. Since the energy density of lithium-ion batteries is lower than that of gasoline, the work of increasing energy density has been going on, and the progress of battery technology depends on the continuous development and improvement of new systems. At the same time, ensuring the safety of lithium-ion batteries with high energy density has become an arduous and necessary task. [0003] Lithium-ion batteries may encounter unexpected situations such as puncture, extrusion, and overcharging during use. To improve the puncture resistance of the...

AI Technical Summary

Problems solved by technology

Disadvantages: The temperature difference between closed cells and ruptured membranes is only about 30°C. Once the battery temperature reaches 130°C, it will soon rise to above 170°C

Disadvantages: The inside of the battery usually starts to accelerate the reaction before 120°C and heats up rapidly, so the closed cell temperature of 120°C is still too high in practical applications

It is speculated that although the PE micropowder has reached the melting temperature, the viscosity after melting is still relatively high, and the distance between the micropowders is relatively large, so it cannot be fused into a whole quickly.