Ugh, that really stinks. I started to look into battery options and lithium ion is really expensive in any reasonable size. Like 5 to 10x more expensive than lead acid. I was thinking it might be nice to use a few smaller lithium batteries with an easy way to swap them out. So for a weekend trip maybe get by with one or two and rotate them. Something like: http://amzn.to/2ikNrBI
Another option is to mount the battery on the underside of the trailer as others have done. You’ll need to figure out how to waterproof it and protect it from road debris but at least it would be putting stress on the flat.
Slightly off topic, this is at least the second galley flat failure I’ve seen in the forum. I noticed that in the latest Waterlust build video it looked like they glassed the flat. I don’t recall seeing that in the manual but now I’m thinking that at least tape on the inside seams would be a good idea if not glassing the entire flat and bringing it up a few inches on the sides and back. Thoughts?
-mike