Lithium Iron Phosphate (LiFePO4 or LFP) Battery
A Lithium Iron Phosphate battery is a type of rechargeable battery that uses lithium iron phosphate (LiFePO4) as its cathode material and carbon graphite for its anode. These batteries offer high safety and are highly stable in high-temperature environments.
LFP has a nominal voltage of 3.2V per cell. LFP is the safest type of lithium battery because it has extremely low thermal runaway. LFP also has a long lifespan with up to 8000 cycles at 100% depth of discharge (DOD).
Ni-Mn-Co Battery
Ni-Mn-Co is a type of lithium-ion battery that uses nickel, manganese, and cobalt as its main materials. They are suitable for applications where high capacity is required, such as electric vehicles, power tools, and consumer electronics.
NMC batteries have a nominal voltage of 3.6v per cell and have good power performance due to their higher operating voltage compared to other chemistries. NMC batteries typically have about 500-700 cycles at 100% DOD, making them half as durable as LFP battery.
1.Cycle Life
LiFePO4 batteries have a very similar cycle life to NMC at low depths of discharge (DOD). At 100% DOD, however, LiFePO4 can last over 10x longer than NMC.
2. Charging Efficiency
Charging efficiency is defined as the energy that goes into the battery (measured in watt-hours) divided by the energy that comes out of the battery (also measured in watt-hours). LiFePO4 batteries have a charging efficiency of about 95%. This means that 95-watt hours go into the battery for every 100 watt hours taken out. NMC batteries have a charging efficiency of about 85%. This means that 85-watt hours go into the battery for every 100-watt hours taken out. When comparing these two chemistry types, it can be seen that LiFePO4 is 10% more efficient at charging than NMC
3. Safety Considerations – LFP vs NMC
Since a battery operates at high voltage and can reach a high temperature, safety is vital. Battery safety includes both high thermal stability and chemical stability. NMC batteries have stable chemistry. However, the battery chemistry results in the release of Oxygen. Therefore, improper construction or inappropriate battery use can make it catch fire or explode. LFP batteries have stablechemistry and can handle high temperatures quite well. They don’t overheat, so there is no need to worry about the temperature threshold at all. Additionally, there is no oxygen release from LFP batteries. So there is no concern about flammability even at a high temperature.
Verdict: LFP batteries win again on safety criteria. One thing to note is that all lithium batteries have high safety compared to lead-acid batteries.
4. Product Lifetime – Charge Cycles of LFP vs NMC
An NMC battery has an expected cycle life of about 2000-2500 cycles. It can provide full power for about three to four years but then suffers fast degradation. An LFP battery has a typical cycle life of about 5000 cycles. It can perform optimally for seven to ten years, followed by slow degradation.
Verdict: LFP technology produces a significantly better battery cycle life than NMC batteries and can last twice as long.
5. Product Lifetime – Discharge Cycles of LFP vs NMC
NMC batteries, like other Lithium-ion batteries, have a DoD in the range of 80% to 90%. This is much better compared to lead-acid batteries (50%). The depth of discharge for a typical LFP battery is an astonishing 100%. This means you can use all the stored power in the battery without any worry about damaging it.
Verdict: Both batteries have a good depth of discharge, but LFP batteries are the winner. A 100% depth of discharge also reduces the oversight required by the battery owner.
6. LFP vs NMC batteries – Price
NMC batteries are expensive because of the materials used in the battery. NMC batteries require Nickel, Manganese, and Cobalt in considerable quantity for the cathode material. LFP batteries are cheaper than NMC batteries because they use iron and phosphate as cathode materials, which are abundant and cheap.
Verdict: LFP batteries have a significant edge over NMC batteries when considering the cost per KWh of each battery type. Couple this with the longer lifespan LFP technology offers, and LFP batteries are clearly the winner, offering the best value for money.
7. Self Discharge Rate
NMC batteries have a self-discharge rate of 4% per month. LFP batteries have a self-discharge rate of just 3% per month.
Verdict: These two technologies have admirable self-discharge rates, with LFP batteries offering slightly better performance.
8. Thermal Runaway
The Ni-Mn-Co Battery family is known for thermal runaway. In fact, thermal runaway is the exclusive property of this battery class. In the Mexican heat, overheating can occur, which can lead to an explosion. Since LFP batteries do not overheat, there is no thermal runaway. Even at high temperatures, the Lithium Iron Phosphate compound is stable, which eliminates the possibility of thermal runaway.
Verdict: Comparing the risk of thermal runaway for NMC vs LFP, LFP is the clear winner, as it eliminates any concern about thermal runaway in the battery.
9. Environmental Safety
NMC batteries use cobalt as the cathode material, which poses a considerable environmental risk. Using cobalt cathode materials creates toxic fumes throughout the battery’s lifetime and even after disposal. LFP batteries are cobalt-free, so there is no negative environmental impact at all. In fact, LFP batteries are one of the most environmentally friendly battery technologies.
Verdict: An LFP battery is the best choice for people who want a green battery. Additionally, the longer lifespan of LFP batteries means fewer battery changes are needed.
10. Comparing Lithium NMC vs LiFePO4 in terms of power and voltage delivery: how do these two battery technologies compare?
Lithium NMC batteries offer stable power delivery, with little variation in voltage output even as the battery discharges. This makes them ideal for applications where consistent power delivery is crucial, such as medical devices or electronic cigarettes.
In terms of voltage delivery, lithium NMC outperforms LFP. The average voltage output of a lithium NMC battery is about 3.7V, compared to 3.2V for a LiFePO4 battery. This higher voltage makes lithium NMC batteries better suited to high-power output applications, such as electric vehicles.
LFP batteries also offer stable power delivery, but their voltage output may drop rapidly as the battery discharges. However, this decrease in voltage is much less pronounced than with other types of Lithium-ion batteries, making LiFePO4 a good choice for applications where stable power delivery is important.
Verdict: LiFePO4 lithium iron phosphate batteries are the clear winner on stability. However, lithium NMC batteries may be a better option if you need a battery with high power output
As with any decision, there are trade offs. Both LFP and NMC have their pros and cons in terms of performance, life, cost, and safety. Since some applications require a higher amount of energy whereas other applications require high power output, the choice between the two depends on your requirements. Broadly speaking, LFP has a longer cycle life than NMC but offers lower energy density. This means that for applications where higher energy density is required, such as electric forklift, NMC is generally chosen over LFP. However, for applications where longevity is essential such as grid storage or uninterruptible power supplies (UPS), LFP is usually preferred over NMC. Here are other reasons why LiFePO4 may be a better option:
● LiFePO4 batteries are safer compared to NMC batteries
● Lifepo4 batteries have longer lifespans
● LFP batteries are the most stable chemistry for Lithium-Ion.
● LFP is environmentally friendly.
● Compared to other lithium-ion batteries, LFP batteries have a higher discharge rate.
● While NMC batteries can undergo thousands of cycles before failing, LFP batteries can undergo tens of thousands of cycles without degradation.
● Lithium iron phosphate batteries are also less likely to have thermal runaway (fire).
Battery manufacturers such as Contemporary Amperex Technology Co. Limited (CATL), Panasonic, Samsung SDI, LG Energy Solution, and BYD are rapidly developing new batteries that are more energy dense, lighter, safer, more sustainable and, importantly, affordable.
Conclusions
Being less expensive and more reliable than NMC batteries, LFP batteries remain the most convenient and affordable technology on the market for many applications, including EVs and off-road electric industrial vehicles.
LFP technology continues to advance on both the cell and pack levels with CTP technology. Furthermore, an improved Battery Management System (BMS) optimizes each cell discharge in real time and provides incremental gains in a battery’s everyday performance, and also extends its cycle life.
