There are several main types of lithium batteries. These types of batteries differ by their chemical composition which in turn produce different energy and power densities, cost and safety levels. It is important to understand these differences. EnSol uses lithium-iron-phosphate chemistry as it is the safest type of lithium batteries.
Lithium-iron-phosphate batteries (LiFePO4)
These batteries have high thermal and chemical resistance. This is one of the safest lithium-ion batteries. Even in the case of a short circuit of the electrodes or wrong polarity during charging, there is no spontaneous combustion. These batteries also remain operational in the case of external excessive heating. Lithium-iron-phosphate batteries are capable of withstanding up to three thousand recharge cycles. These batteries have somewhat less specific energy density than NMC or Cobalt-based chemistries, but are capable of withstanding high currents, and, accordingly, have higher power. EnSol uses lithium-iron-phosphate chemistry in its batteries as this is the safest and the strongest chemistry for use in heave electric industrial vehicles like forklifts.
Lithium-cobalt batteries (LiCoO2)
The main advantage of lithium-cobalt batteries is their high specific energy intensity. As a rule, they are used in batteries of portable electronic devices, laptops and mobile phones. Despite the good characteristics, these batteries have less stability in abnormal modes. Too large discharge current, overheating, or mechanical damage can lead to a thermal runaway. For this reason lithium-cobalt batteries are not used in electric vehicles and other traction devices.
Lithium-magnesium batteries (LiMn2O4)
Lithium-magnesium batteries have a higher voltage than lithium-cobalt batteries. Another positive quality is their thermal stability. The life cycle of these batteries is about one thousand cycles. They have a slightly lower specific energy, but these batteries are able to operate at sufficiently high ambient temperatures, are environmentally safe and have a low cost.
Lithium-cobalt-magnesium batteries (LiNixCoyMnzO2)
These batteries are the best choice for those cases where good performance is needed at a low battery cost. The specific capacity of lithium-cobalt-magnesium batteries is higher than that of lithium-iron-phosphate batteries, and the specific power is higher than that of lithium-cobalt batteries. These batteries are an alternative to lithium-iron-phosphate batteries, since they have similar characteristics at a lower cost. One of the main applications is energy sources for electric vehicles.
Lithium-titanium batteries (Li4Ti5O12)
In these batteries, instead of the graphite anode, an anode is used from lithium titanate. They have good specific power over a wide range of temperatures and are considered a safer alternative to batteries using graphite. Another strong point of lithium-titanium batteries is a good service life. Their only drawbacks are high cost and relatively small specific energy.