Lithium batteries
I know little about automotive applicaitons for lithium, except this:
(We sell and use lithium 24V and used to use 48V in our power wheelchairs)
These are LiFePO4 nominal 24V system, 100AH
So far as I know ALL high power lithium batteries MUST have some sort of electronics management package
You can not tell charge level by measuring voltage, as you do with a lead based battery, The voltage curve is quite flat until the battery is nearly depleted, giving you a "false sense" of charge level
The charger MUST BE specifically engineered for lithium, and they will only charge "so fast."