Electric Skateboard Calculator | ESK8 Calculator - What size, Motor, Battery, Wheel, Belt to use?

Got really sad then my favourite calculator which I was opening more than once a day got closed so I spent today’s evening trying to my own small implementation which I will try to add lots of features.

Todo List:

  • Shareable URL which would save your inputs
  • Recommended VESC current ratings based on inputs
  • Add many style graphs for e.g. (motor/bat current duty cycle relationship), (battery voltage/speed relationship)

If someone has some more ideas hit them up I will try to implement them all :slight_smile:

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Nice! I too got very sad to see it go down, thanks for putting in the work for a replacement!

Some feedback, Your watt hour calc looks wrong though, shouldn’t you use nominal voltage instead of full charge voltage?

Second, it would be nice to be able to input max amp charge rate instead of just C rating… And choose A or mAh on capacity.

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I always counted Wh with max voltage as it’s still usable watt hours :slight_smile:

I will implement this later on, this was quick iteration :slight_smile: I wanted to keep simple. I don’t know many other 18650 cells which allow more than for e.g. 2C charging current and lipos are all C rated :slight_smile:

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What does the currents section mean? My 10S4P 20A 2500mah cells are saying 350A constant discharge? I think that should be 80? Something to look at there?

Same with the power, the numbers seem off by a power of ten, but if corrected still slightly lower than I’d expect.

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Opsy :sweat_smile: copied bit too much code from wrong place :slight_smile: Fixed should work correctly :slight_smile:

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Nice, looks just right now! :sunglasses::sunglasses:

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@Kug3lis My hero! :smile:

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This is how my crazy 2 x 80100 setup looks :slight_smile: Looks pretty accurate… :smiley: 72Nm drive train… Polo 1.2 has 107Nm iirc :smiley:

image

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Wow well done already I have it that the numbers of the results are cut in half because the borders are very little (if you understand what i say) I see that you don’t have that so how can I fix it? or is it a bug

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Looking awesome, battery options are really nice and understandable. Just a quick question, I’m guessing motor wattage is per motor?

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Seems wrong to me - Wh is the total energy in your pack. You don’t use the pack at 42V all the time. The reason to use the nominal voltage is that it gives a good estimate for the average voltage the pack will be at. Some time will be at higher than nominal while around the same time will be spent below the nominal voltage. See this for a quick and dirty illustration of what I mean.

Edit2: Even more obvious: an actual Wh graph from lygyte

so we see a single 30Q has around 10 to 11 Wh - which can be estimated quite well with 3.6*3000mAh.

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This. 10char

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I don’t think the lipo selection is working, I can’t seem to get data to work while using a lipo set up. I did just change to 18650 and put in the correct values and it’s great. Love how it displays torque output, that would be fun for comparing. IDK how you are making 72Nm mine says 7Nm lol

Great work man

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Nice work! It would be nice to be able to set the exact kv value though

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It does, does it not? isn’t it called speed/volt

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Nice work @Kug3lis

I think the range estimation is wrong by a factor of 2, maybe something do with the number of motors, a 370Wh battery is only giving me 19km of range using 10 Wh/km

I would like to have maximum grade and what speed it can climb that maximum grade based on the maximum duty cycle that respects the battery maximum current proportional to motor max current

If you want I have the formulas ready in my own spreadsheet

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you can set it to 170, 180, 190 aso. Typing in other values highlights the box as if it’s not an accepted value (?)

Wh consumption is for one motor, so even if you have 2 motors, you should enter value for one motor only. Range looked right to me anyway

Would you consider opening the source code for the calculator? I could help you implement somethings.

For example, a toggle for metric/imperial instead of having both at all times.

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That makes no sense, consumption is a variable of the system, you don’t say your car does 10 mpg per piston