A couple of comments:
1. What are the available charge profiles on your ZAMP controller? LiFePO4 is really not that picky, so one of the existing profiles may work well enough. There are also other reasons to upgrade, but it may not be a requirement.
2. Look beyond Battleborn for a replacement battery. The price of LiFePO4 cells has dropped dramatically in the last year or two (just like solar cells). Battleborn was always a bit on the pricey side, but given the market shift they have become significantly overpriced. There are already a bunch of competitors out there at about 60% the price of BB, some with more features, and I think in the next few months there will be a further drop in prices. There are also some 120 - 150Ah batteries that would likely fit in your battery compartment, meaning you would definitely only need one battery.
Edited by rando, 12 January 2021 - 05:46 PM.