Flame REsistant Glass fibers for bATTeries Housing for electric vehicles (FREGATT)

Purpose and goal:

In this project we have investigate the possibility of increase of the flame retardancy and fabrication of the flame resistant composite structures, particularly laminates for TVs batteries casings. Effect of graphene is proven on the glass fiber, via optimised coating, and improvement of the flame resistance by factor of 10 and being additive. On the other hand, it is concluded that creation of the TVs casings with advanced flame resistant characterisics requires also respective engineering of the epoxy resin, which is used for the laminate manufacturing.

Expected results and effects:

Graphene coating allows effectively create the flame resistant glass fiber fabric, upon lightweight and thin coating. Indeed, optimised samples of glass fiber were coated by only 4 gr/sq meter of graphene, improving their fire resistance by 10 times (70 vs 7 sec.). It is shown also that increase of the number of fabric layers will increase the burning time respectively and additively (4 layers - ca 256 sec).

These impressive results do not however transfers directly into composite/laminate, due to detrimental role of the epoxy resin. The efforts thus has to be put on upgrading the resin. Approach and implementation:

Graphene coated glass fibers were incorporated into an epoxy, forming the composite materials, laminates. First, we identified the required glass fibers and epoxy resin, standardly used in automotive industry. Then we have found the optimal thickness of the coating for glass fabric, which provides longest fire retardancy time at lowest weight increase.

Second, we have optimised the laminates design. Finally, the laminates were made and their flame retardancy was measured according to ISO 5660-1 Cone Calorimeter Test.