In today’s residential solar energy storage market, two of the most popular type of Li-ion batteries are NMC and LFP.
These two acronyms refer to what the cathode inside the battery cells are made of.
An NMC cell has a cathode made of Nickel, Manganese and Cobalt
An LFP cell has a cathode of Lithium Iron Phosphate
The Li-ion, after which both the batteries are named, refers to the electrolyte (fluid) that contains the Lithium ions.
The differences in these materials result in slightly different performance characteristics of each battery type.
It is important to note, however, that both NMC and LFP batteries are very well suited to home solar storage.
These are common in smartphones, laptops and electric vehicles as well as home energy storage. A popular NMC battery on the market today is the Tesla Powerwall.
LFP batteries are less toxic than NMC batteries and thus easier to recycle - more and more companies are now manufacturing LFP batteries.
So which is better?
More or less the same. NMC can be better in very cold weather, but LFP can be better when the state of charge is very low. These small differences should not really affect your purchase design, however.
LFP will have a longer lifespan than NMC, but in general, with average use, you should expect either to last 10 years.
LFP are also considered a bit safer since their energy density is lower. This also makes them bigger and heavier in some case, compared to their NMC equivalents.
NMC tend to be cheaper, mainly because of economies of scale are larger for this battery chemistry for now.
In summation, LFP batteries are a little bit better, and a little more expensive.
The difference between the two is smaller than the difference between a good, knowledgeable installer and one who is not!