There is a lot of new and exciting info on the Lithium front.
Prices are dropping in fact they are now in line with Trojan T-105's and should continue to drop farther.
However so far only half the technology is there for the most part in the RV world.. The battery itself.. The Chargers are still a bit .. er... rare (As it happens I have one but I do not trust it).
Now one of my chargers is a Xantrex Prosine 2.0, fully programmable it can be set to charge Lithium batteries of assorted types.. but ... For reasons i would rather not go into I don't trust it (I need more testing before I can comment.
In fact I don't use it for my Flooded wet cells (I use a Progressive Dynamics Intella-power 9180 with wizard).
But not many chargers are that programmable.
And Li batteries get real nasty if not properly charged.
That, howevever, is what companies are working on, making them safer and safer and lower and lower in cost.. I expect soon to be changing over myself .
