lithium batteries

Lots of misinformation out there about LiFePO4 batteries. That's one of the problems. There are quite a few of live aboard boaters using them for a couple years now and really pleased with them. These are not the cobalt based batteries in the Boeing aircraft that had problems. These are actually newer technology and very safe.
It is possible to put together a LiFePO4 system of comparable AH for about the same cost as AGM batteries.