Battery versus latex coated felt

[elanJack]

I'm mid way through a long S3 restoration, battery installed and connected to a battery condition charger. I have just noticed that the latex coated felt I glued to the inner wing behind and to the front of the battery is deteriorating so I had to remove the entire piece, see picture, (this piece was glued to the inner wing and not under the battery). The latex is still good but the felt has disintegrated into a rust coloured slightly sticky dust. No obvious signs of battery acid leak all sides, top & bottom are dry so I am assuming that the battery is venting whilst on charge? Or could it be something else? All other felt in the boot is still intact so is it because I bought a cheap battery?

[Slowtus]

Batteries DO vent while on charge and the surrounding areas will suffer as a result - the amount of damage is material dependent.