If the first Lithium batteries were considered dangerous, those sold under the name Lithium Iron Phosphate (LiFe PO4) are much safer because of the chemical composition of their cells.
Especially since they are mostly equipped with a BMS (battery management system) which balances the cells between them while preventing overvoltage or undervoltage of the battery.
The advantages of Lithium over older generations of batteries are real.
- They are 3 times lighter than lead batteries for an identical nominal capacity.
- They are also very energy efficient, as they easily reach 100% recharge of their nominal capacity against 25 or 30% for lead batteries.
- They have a very rapid end of charge and an absorption cycle time reduced to the maximum.
Lithium batteries adapt to all your equipment on board (230V chargers, solar regulator, alternator). However, it is necessary to check the compatibility with the manufacturers of this equipment.
Another advantage, the deep discharge. Indeed, lithium batteries can be discharged to 90% while closed liquid lead batteries can only be discharged to 50%.