I've got these felt sheets about 5mm, it's a very good heat insulator and can withstand high temperature.

Been reading about battery heat shield but lack of the tools to DIY it until my tools arrived.

So using NS40ZL size I determined that it's 20cm X 13cm X 22cm (height)
The connecting edge I use very thick paper clip to lock them up.

Then I slit many cuts to fit battery mount, and to allow better terminal inlet.

Tomorrow gonna drive it for like 20min, then will put my hands in between the felt sheet and battery to feel how warm is the battery.



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Bro, check out my DIY heat shield for my 15year old car

Erm, won't be combustible. Felt is hard to catch fire even if burn directly

I tested it on stove. I think for it to melt and burn, whatever plastic inside engine bay will also melt d.
At those temperature fuse box plastic, connector plastic all burn d. If not mistaken felt is PET material.

I did use the same felt for my sun roof heat shielding, it definitely works as a heat insulator