Lithium Iron Phosphate Batteries & Battery Packs
Lithium iron phosphate (LFP) batteries are a variety of rechargeable lithium-ion battery. These batteries use LiFePO4 as their cathode material, instead of the LiCoO2 design more common to battery packs in consumer electronic devices. LFP batteries are different than other lithium-ion batteries in several ways, and offer several distinct advantages.
Although lithium iron phosphate batteries have lower energy density than other lithium-ion chemistries, they provide better power density and longer life cycles. LFP batteries also have higher current (peak-power) ratings than LiCoO2 batteries, and a lower self-discharge rate than LiCoO2. LFP batteries experience a slower rate of capacity loss than other lithium-ions when not in use.
LFP batteries’ LiFePO4 cathodes also offer the safety advantage of having more thermal and chemical stability than LiCoO2 cathodes. Because of stronger chemical bonds between the elements involved, oxygen atoms are not as readily removed from LFP cathodes due to abuse (overheating, short circuiting, etc.). In similar circumstances, LiCoO2 batteries undergo non-linear expansion that affects the structural integrity of the cell. Oxygen loss in LiCoO2 cells also leads to exothermic reactions which can in turn lead to ignition in the event of mishandling.