Range calculator?

#1

Hi guys - this forum looks sick! I’ve built one and two half diy electric skateboards and am excited to get started on my first electric foil board

I have 90 li-ion 18650 cells (2.9ah) and a vesc 6 that I WAS going to use for an electric skateboard but would like to use them on a foil board instead now. Do you think a 12s7p battery will be sufficient re. speed/torque/range? For an electric skateboard, that would be way overkill (range-wise). I read somewhere on this forum earlier today that 16ah will give roughly 50 mins of riding time

But based on the image of the battery of the Lift Foil on their website, it looks like they are running a 14s14p with 1 hour of ride time at 15 mph (I literally just counted the cells in the photo)… I dont mind buying more cells if necessary, but a 14s14p battery seems insanely huge! Plus if I go 14s I wont be able to use the vesc 6 I already have and my project will be a lot more expensive

Basically, I’m wondering if there is there some sort of a calculator/ standard to reference for range?

#2

Don’t worry about the range for now. You can always add more batteries if you have space. I am also going for the VESC6, but I didn’t test anything yet. I am hopeful. My guess it that a lot of it comes down to prop design.

#3

Okay true…theres just a pretty huge difference between 12s7p and 14s14p lol

I havent even begun to learn about prop design yet

I was reading your thread earlier - looks sick! Love the custom board. What battery are you using?

#4

I still hope we find some prop expert that will design the ultimate prop for the forum.

I use 4x 10Ah Lipos from Hobbyking. They cost me 250€ with shipping.

#5

Like at ESK8 it depends on your setup. People in the forum here are telling something between 1200-3000W for foiling. Depending on your weight, foil, prop, motor, etc…

So with 12s7p of 2.9Ah each you get a pack of ~900Wh.
Most important at first is, that your battery pack can deliver the Amps needed to get foiling.
So e.g. if you set the VESC for max 100A battery current your 7p 2.9Ah have to have at least 5C (or 15A) discharge.
If that is given you can calculate a best and worst case (till you test how much your setup really needs): best case: 900Wh battery / 1200W load = ~0,75h = 45min
worst case: 900Wh battery / 3000W load = ~0,3h = 18min

To increase your runtime you can later just add some more cells in parallel (then your batterypack grows from 12s7p to maybe 12s10p or 12s14p, whatever you like and have money and space for).

#6

Thanks! That was very helpful. Will probably do 12s10p to start

#7

Which cells do you have?
Personally I would make sure to stay far away from the maximum discharge rating.

How many amps/watts do you plan to build your system for (wire gauge, motor, VESC)?