LFP vs. NMC - Long Term Vision

Reasons the world is shifting to LFP.

Thanks for returning, I hope you had a chance to review my previous two articles on LFP and the advancements made in its industrial development.  

As the global charging infrastructure grows and raw materials drop in price it introduces a new dynamic for an electric vehicle network.  The use of NMC cell chemistry was necessary to achieve the highest specific energy battery packs for maximum range.  Consumers have demanded that a vehicle provide 300+ miles (482 km) of range to convert them away from internal combustion vehicles.  

Tesla has set the bar, and we are seeing regular news from other automobile manufacturers that even more models will supply this range on a full charge.  Although exciting; is this actually the direction that manufacturers should focus their efforts?  What will force the switch from NMC to LFP?  I believe the three most important considerations; time, money, and corporate responsibility are signaling the market has peaked for NMC (at least for R&D and innovation efforts). 

First off, does LFP save time for the driver?  People, in general, will always make comparisons to their existing beliefs or experiences.  When refueling an empty gasoline powered vehicle in the United States it will take roughly 1-3 minutes depending on tank size.  The flow rate for gas dispensers is limited to 10 gallons per minute.  Whether that fill rate is always 10 gallons/min is something that you can check next time you go to fill up.  For electric vehicles there are three different chargers (Level 1, 2, and 3) that can be used.  Level 3 chargers supply the fastest charging speed, and are most likely what you would use at a rest stop during a long road-trip.

Currently, Tesla V3 Superchargers have some of the highest charge speeds.  Tesla states the Model 3 can be charged at a rate of 250 kW which is fast enough to supply 15 miles per minute.  If we use the benchmark of a 300 mile range, this would suggest that premium V3 Superchargers can charge a fully depleted Model 3 to near 100% charge in 20 minutes.  Obviously this is still quite a bit longer than filling a gasoline powered vehicle, but it is not that far off.  When traveling it is common to stop for gasoline, but you may also use the restroom or grab a snack.  This can quickly turn a stop for gasoline into a 10-20 minute rest stop.  

As mentioned in part 1 of my report, LFP chemistry is a much more stable chemistry and can withstand higher discharge currents.  This means that the battery can be cycled faster, and is more stable than NMC under normalized conditions.  In part 2 I reference that if the best LFP pack has roughly 56% the specific energy of NMC packs, then this would yield a range of roughly 150 miles.  If this fully depleted battery were charged at the same 250 kW rate it could be charged to near 100% in 10 minutes, half the amount of time as the Model 3.  

Now that we have shown that time to charge the battery can be reduced we introduce the charging and maintenance costs.  There are plenty of reports out there showing the continued decline in lithium and battery costs.  This is further driving down the cost of production, and opening up possibilities for Li-ion batteries of many different chemistries. See figure below. 

Source: Battery University

LFP batteries also have better cycle life than NMC, and therefore under normalized conditions they will last a longer number of cycles.  This means that it could extend the life-time of an electric vehicle.  Charging and maintenance costs according to AAA are also cheaper compared to gasoline powered cars, because there are fewer mechanical moving parts and no need for oil changes.

Finally, Li-ion batteries have generally needed some amount of cobalt for improved stability.  The majority of the world’s cobalt (60%) comes from the Democratic Republic of Congo.  Unfortunately, there are a lot of issues with child labor, and corporations throughout the world are trying to minimize their reliance on the precious element.  They want to send a strong message to the country, and not let those bad practices tarnish their Company’s reputation.  

I believe that the improved cycle life will correspond to net cost savings over the long run that will be particularly appealing to both manufacturers and consumers.  Corporate responsibility will also drive more and more R&D efforts toward developing chemistries without cobalt.  Lithium iron phosphate is one of many such chemistries, and its cycling stability is the reason why it has the potential to make significant in roads into the market!

P.S - stay tuned for Tesla’s Battery Day on September 22nd.  It may provide some further insight into long term strategy for the industry.