I’m looking for a lightweight method to seal a small 6s3p battery for a foil drive system. Shrinkwrap doesn’t seem like it would be very waterproof, as water could seep in at the ends, and glue likely wouldn’t stick to the shrinkwrap.
Has anyone tried using a water based liquid polyurethane waterproofing membrane, such as bostik dampfix gold? I was thinking of applying it over the top of a fully kapton wrapped battery pack, so that it doesn’t soak into all the gaps between the cells. One issue will be the smallest size you can get this liquid membrane, which seems to be 4L, and it has a short shelf life of a few months once opened.
Any other suggestions for a lightweight and thin flexible membrane, either liquid or adhesive backed, to seal my battery packs? Plastidip, polyurethane pcb conformal coating?