Ah okay.
Lithium ion is used over FLA (flooded lead acid) as it has more usable capacity while being more bang for buck density wise... One can drain a lithium completely while with FLA you only have 50% of the usable watt hours. ie. your cell phone battery vs a deep cell golf cart battery.
Lithium ion batteries weigh less than FLA.
Lithium ion can be rapid charged if one has the right type of programmed charger, and of course the high current charging set up... (which is also the main failure point of lithium ion batteries or any battery for that fact).
Lithium ion is maintenance free.
My opinion on the matter:
If one has the time and skill. I would order LiFePO4 batteries from china and build your own battery bank and charging setup. which can be used by these
batteries (why? because all of the batteries are mostly coming out of china anyways), or get some new/used Tesla 2170's and build the right connections of parallel and series to get 48V.