Aptera 40 kWh Efficiency Deep Dive by MotorMatchup

[Thomas Bushaw]

Here’s a fascinating video published today (May 20, 2022) by MotorMatchup:

Solar Powered EV!? Aptera Battery and Efficiency Analysis

He provides a detailed and analytical look at the 40 kWh battery pack (using data provided in Aptera’s recent Battery Update Video). He goes on to delve into the efficency of the vehicle as a whole, using the modeling techniques used for his MotorMatchup EV comparison tool (very fun to play with!).

All in all, he has very positive things to say and share regarding the Aptera. He even provides a calculation that the Aptera could (there are caveats!) motor along at 18 mph using just the 700 W from its solar panels alone.

[Curtis Cibinel]

He did a solid analysis and presented it extremely well.

We don’t have final statistics so details like rolling resistance, weight, frontal area, aux drain and cells are educated guesses or unconfirmed. He does make the assumption that Aptera will still have 0.13 Cd which seems unlikely given the unfortunate need for mirrors (thanks NHTSA). He is also assuming a ~25 sq ft of frontal area which is comparable to a model S; 22-23 is more likely based on the STL file sent to ambassadors when viewed to scale (I previously assumed 20 myself but believe it was low). I updated my calculations based on this and split the difference on some other details and it seems to model very plausibly at all scales except the base 250 mile since 4 modules similar to those described overperforms by ~20 miles of range.

https://docs.google.com/spreadsheets/d/1Tuu7avKH2dS_JPk7aiP2av09a1f1WE0OvvNH6fdHpiQ/edit#gid=1285203539

[Matthew Manzi]

Great spreadsheet Curtis. It really gives a lot of useful information. The only thing I think that is a little off is the cost per cell. I can’t find good info on the cost per cell of this type but I can for cost of NMC cells per KW and it is about 110 dollars at the cell level for 2021 and could raise to 135 at the cell level according to this Bloomberg article. https://about.bnef.com/blog/battery-pack-prices-fall-to-an-average-of-132-kwh-but-rising-commodity-prices-start-to-bite/#:~:text=We%20estimate%20that%20on%20average,closing%20in%20on%20%24110%2FkWh.https://about.bnef.com/blog/battery-pack-prices-fall-to-an-average-of-132-kwh-but-rising-commodity-prices-start-to-bite/#:~:text=We%20estimate%20that%20on%20average,closing%20in%20on%20%24110%2FkWh.

That puts the cell cost at between 5000 and 6000 dollars for the 40 kw pack.

[Curtis Cibinel]

Recent metal prices have likely brought prices up. My method was to look at the retail 2170 cell market and take an additional 10% off their price for 1000+ cells. I also used a inr21700-50e which is cheaper and more available; the inr21700-50g cells are hard to find and expensive. It is possible Aptera will be able to get cells cheaper but probably not the 35% less that you are suggesting. I also listed a alternative cheaper cell; Samsung are the industry gold standard but as a result are more expensive. If they can get the cells for cheaper that is good because the 1000 mile version will need a absolutely nuts amount of cells (likely 3x that of the current 400 mile pack). Battery cells are a expensive high demand commodity and Aptera will likely need to pay a premium over established companies as a result of lower volumes.

[Stefan Obel]

Great info!
Thanks for posting.

[Qiang Fu]

Great info indeed! Thanks!

One question: given the airplane-like shape of Aptera, whether a significant lift would be generated at high speed, which could lower the load and rolling resistance?

[Oz (It’s Oz, just Oz)]

QF, the design is actually set up to provide downforce at speed to keep the vehicle stable, however, as I recall it is balanced to end up with only the needed amount of pressure to keep the load and rolling resistance low.

[Qiang Fu]

I see. That makes sense. Thanks, Oz!