"Any electrification should start with LFP cell chemistry," says Dr. Kai Vuorilehto, Director R&D at EAS Batteries. "It offers the greatest possible safety." Lithium iron phosphate (LFP) has many outstanding properties: it is durable, robust, insensitive to extremely high or low temperatures, ethically clean (no cobalt, no nickel), sustainable, stable in price - and thus absolutely future-proof. But above all, LFP is considered highly safe, even in the event of mechanical damage to the outer cell. "LFP also enables extremely fast charging," adds Dr. Kai Vuorilehto further. This predestines the cell chemistry for applications in the high-power range, for example for dynamic acceleration in hybrid applications in space or shipping. The EAS standard cells "50-Ah", "40-Ah" and "22-Ah" are therefore based on the safe cell chemistry LFP.
Maximum experience: LFP is EAS standard
Especially for manned applications in space, at sea, in the air and underground, LFP is used to protect people from fire in a closed room. "From this point of view, the lower energy density of LFP compared to conventional cell chemistries hardly matters," explains Dr. Kai Vuorilehto. Currently, the adjunct professor at Aalto University conducts his research exclusively in Finland, but he usually commutes between research laboratory in Helsinki and the EAS production site in Nordhausen on behalf of continuous cell optimisation. Dr. Kai Vuorilehto has been working with the LFP cell chemistry since its market launch and thus, like EAS Batteries itself, has the maximum experience with lithium iron phosphate.
Chemical facts: LFP allows safe use of lithium
The cell chemistry LFP is the reason why lithium-ion batteries can be used in safety-relevant areas at all today. Its components lithium, oxygen, iron and phosphorus combine in tridimensional form. This prevents the oxygen from being released - unlike in classic Lithium-ion cells with layered components such as cobalt (C), nickel (N) and manganese oxide (M). To charge or discharge a Lithium-ion cell, the lithium moves to the negative or positive pole, as respectively required. The LFP cell remains temperature-stable - even if the lithium is completely at one pole. With the former cell chemistries, a maximum of fifty to seventy percent of the lithium ions are allowed to migrate, otherwise the cell heats up. This makes them much more vulnerable and their use more risky, because combined with the released oxygen and the flammable carrier liquid (electrolyte), a heated classic Lithium-ion cell immediately catches fire or explodes. The safety of a LFP cell is therefore based on two of its inherent facts: Lithium iron phosphate binds oxygen strongly and the cell remains temperature-stable.
Innovative cell chemistry: the future lies in LFP and LMFP
Currently, the NCA, NMC and LFP compositions dominate the cell chemistry market. "All lithium-ion batteries are continuously developed, optimised and thus improved by one or two percent every year," clarifies Dr. Kai Vuorilehto. Still, in his estimation, cobalt-based cell chemistries have little future. "Cobalt is anything but sustainable or ethical. It will also become scarcer and therefore more expensive," he explains further. "The future of cell chemistries may lie in a manganese-iron phosphate combination called LMFP."
LMFP offers more energy than LFP, with a tridimensional structure as well. It is therefore similarly safe as pure LFP. However, the development of LMFP is still in its beginning. But again, as was once the case with LFP, EAS Batteries and Dr. Kai Vuorilehto develop innovative technologies based on sustainable cell chemistry from the very beginning.