The type of battery Li-Fe, whose real name LFP are lithium-ion batteries, the cathode is made of lithium iron phosphate. This principle has been diverted from the car on electric models. The advantage of Li-ion batteries airsoft is that it provides a voltage close to the Ni-Mh 9.6v adding the benefit of the Li-Po without unloading problems. Put simply, Li-Fe batteries have a longer life, do not fear the landfill while providing a useful life as long as a Li-Po. This type of battery requires a specific battery charger.