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USB Battery Array -> Power 36v Motor

  1. Sep 7, 2015 #1
    I'd like to take several of these (or similar) usb device charging batteries (http://www.ianker.com/product/A1271011 [Broken]) and connect them into an array to create a minimum of 36V and channel that to power a speed controller for an electric vehicle. Is this possible? Would I be able to prototype something like this with an Arduino or similar? Any advice/direction would be really appreciated.

    Question 2: if this is possible, do the amp hours added together per battery or does that stay a constant? For example, a battery has 2 amp hours - if I have 5 is it a total of 10 amp hours or is it still 2 amp hours?

    Last edited by a moderator: May 7, 2017
  2. jcsd
  3. Sep 7, 2015 #2


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    The Watt hours add together. 72 Whr x 7 = 504 Whr
    If they are in parallel, the amp hours add together, but the voltage stays at 5V. parallel 7 x (5V , 20 Ahr) = (5V, 140 AHr) equivalent 700 Whr
    In series the voltages add, but the amp hours stay the same. series 7 x (5V, 20Ahr) = (35V, 20Ahr) equivalent 700 Whr

    I assume the discrepancy in Whr is due to the fall in voltage during discharge. The conservative 72 Whr per unit is likely to be correct. So
    in parallel 504 Whr / 5V = 101 Ahr
    in series 504 Whr / 35V = 14.4 Ahr
  4. Sep 18, 2015 #3
    maybe I'm missing something but a charger needs to be plugged in to do anything. wouldn't that be an issue for any vehicle application?
  5. Sep 26, 2015 #4


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    The device linked to by the OP is a battery pack that is designed to charge portable devices. Thus a charger. It also likely comes with a plug in type charger. Thus a charger charger.

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