Glass fiber and polypropylene battery case with conductive performance, and making method thereof

Abstract

The invention provides a glass fiber and polypropylene battery case with a conductive performance, and a making method thereof. The method comprises the following steps: sending 40-60% of homo-polypropylene, 10-45% of glass fibers, 10-30% of conductive crystalline flake graphite, 0.5-5% of a compatilizer, 1-5% of a coupling agent and 0.5-3% of a heat stabilizer to a bunker in an LFT-D production line, mixing polypropylene with above assistants, adding the conductive crystalline flake graphite and the glass fibers, and mixing above materials at 220-240DEG C under a mixing rotating speed of 100-200r / min; extruding the obtained mixture, and carrying out heat insulation conveying at 150-180DEG C; carrying out compression molding, wherein the die temperature is 20-40DEG C, the pressure is 1000-2000t / m<2> die projection area, and the dwelling time is 20s / mm thickness; pushing out the obtained product under a speed of 5-20mm / s; and trimming off superfluous material edges. The battery case made through the method has the advantages of conductive capability, operation and artificial cost saving, no peeling risk, and stable electromagnetic shielding performance.

Description

【Technical field】 [0001] The invention relates to a glass fiber polypropylene battery box with electrical conductivity and a preparation method thereof. 【Background technique】 [0002] LFT-D (Long-Fiber Reinforce Thermoplastic Direct) Chinese translation is direct online long fiber reinforced thermoplastic composite material. The key factor that distinguishes it from GMT and LFT-G is that the semi-finished product step is omitted, and the selection of materials is also more flexible. In LFT-D technology, not only the fiber content and length, but also its matrix polymer can be directly adjusted to the requirements of the final part. Typical of the LFT-D process, the polymer matrix granules and additives are delivered to a combination of gravimetric dosing units that ensure proper mixing according to the mechanical performance requirements of the part. The mixed raw materials enter the twin-screw extruder for plasticization, and the molten compound passes through a film die ...

AI Technical Summary

Problems solved by technology

[0003] Before assembly, glass fiber reinforced polypropylene composite battery boxes often need to be bonded with a conductive layer or coated with conductive metal paint on the inside of the shell to enable it to have electromagnetic shielding capabilities, such as copper metal sheets, conductive silver paste, This method of enhancing product conductivity has several serious disadvantages: ①Complicated process, increased labor costs, especially for battery boxes with complex structures; ②There is a risk of peeling

Both the conductive paint and the metal sheet are bonded to the inner surface of the product after the battery box is formed. With the increase of use time and high and low temperature cycles during use, the conductive paint is prone to peeling off, and the conductive metal sheet is prone to degumming