How about 18650 Li-Ion battery pack over the Li-Po packs?

Is the energy density per Kg really that much better? In a previous comment I calculated the energy density of Paul’s Multistar batteries to be 7.5Ah/Kg, with an output voltage around 22.2v. Based on the Samsung datasheet, I calculated that for an output voltage around 22.2v you would have a density around 9.25Ah/Kg. This doesn’t include any housing or protection for the batteries, which would probably drop it down to the same or worse energy density as the LiPos. Am I messing up my math somewhere?

There are however more-expensive graphene based LiPos with casing and a higher energy density at 8.33Ah/Kg, and Paul’s been using some pretty high capacity, high discharge Bonka batteries with an advertised density of 8.75Ah/Kg.

Of course manufacturers could be fuzzing the numbers somewhat, and I could be making mistakes in my Math, but that seems to be where we’re floating around right now: 8Ah/Kg. It would be fantastic if we could find some particular chemistry that takes that number up, but right now I’ll be skeptical until I see evidence strong enough to support a major claim like that.

Finally; we need to make this project simpler, not more complex. People have enough to worry about- wind conditions, staying alert for other air traffic, and everything else needed to fly safely. We need the most reliable, simplest batteries we can get so that people can put cycles into safe aviation decision making and not into worrying about whether their cells are all charged and balanced.

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