Are Lithium Iron Phosphate Batteries Better?

According to the latest news from developments in batteries, the LFP or Lithium Iron Phosphate battery technology is going to pose a serious challenge to that of the omnipresent Lithium-ion type.

As far as e-mobility is concerned, Lithium-ion batteries have some serious disadvantages. These include higher cost and lower safety as compared to other chemistries. On the other hand, recent advancements in battery pack technology have led to an enhancement in the energy density of LFP batteries so that they are now viable for all kinds of applications related to e-mobility—not only in vehicles but also in shipping, such as in battery tankers.

In their early years of development, LFP cells had a lower energy density as compared to those of Lithium-ion cells. Improved packaging technology had bumped up the energy density to about 160 Wh/kg, but this was still not enough for use in e-mobility applications.

With further improvements in technology, LFP batteries now operate better at low temperatures, charge faster, and have a longer cycle life. These features are making them more appealing for many applications, including their use in electric cars and in battery tankers.

However, LFP batteries still continue to face several challenges, especially in applications involving high power. This is mainly due to the unique crystal structure of LFP, which reduces its electronic conductivity. Scientists have been experimenting with different approaches, such as reducing the directional crystal growth or particle size, using different conductive layer coatings, and element doping. These have not only helped to improve the electronic conductivity but have increased the thermal stability of the batteries as well.

Comparing LFP batteries with the Lithium-ion types shows them to have individual advantages in different key characteristics. For instance, Lithium-ion batteries offer higher cell voltages, higher power density, and better specific capacity. These characteristics lead to Lithium-ion batteries offering higher volumetric energy density suitable for achieving longer driving ranges.

In contrast, LFP batteries offer a longer cycle life, better safety, and better rate capability. As the risk of thermal runaway, in case of mechanical damage to a cell, is also much lower, these batteries are now popularly used for commercial vehicles with frequent access to charging, such as scooters, forklifts, and buses.

It is also possible to fully charge LFP batteries in each cycle, in contrast to having to stop at 80% to avoid overcharging some type of Lithium-ion batteries. Although this does allow simplification of the battery management algorithm, it adds other complexities for Battery Management Systems managing LFP cells.

Another key advantage of LFP batteries is they do not require the use of cobalt and nickel in their anodes. The industry fears that in the coming years, sourcing these metals will be more difficult. Even with mining projections of both elements doubling by 2030, they may not meet the increase in demand.

All the above is making the LFP batteries look increasingly interesting for e-mobility applications, with more car manufacturers planning to adapt them in their future cars.