david coffin wrote:so, as voltage goes up, the amperage draw of the relevant motor goes down. theoretically, the same batteries i have would give a longer run time at a higher voltage configuration, no? my current stock of batteries are 6 of the 12 volt, 12 amp-hour rating, lead-acid. i was using them in a 3 bank 24 volt config, for 36 amp-hours. i could also wire them as 36 volts, with 2 banks, for 24 amp hours. or even 72 volts at one bank, for 12 amp hours.
NOOO// the controller regulates the amperage, as laundry said above.. you are still better off in most cases with a lower voltage system , because you simply have to carry less batteries for the same AH//
example / 6 batteries in parallell is 12v 72 ah ( 12 ah batteries for this example )
running a 30 amp comtroller and a 12 v motor , ur run time will be insane
now , take the same 6 batteries, and run series , u now have 72 v 12 ah
your run time will normal , 12ah supply..
NOW the advantage to the 72 v system is that you are running 72 volts times 30 amps or 2100 watts
on the 12v system you are running 12v times 30 amps or 360 watts..
BUT YOUR NOT RUNNING 30 AMPS , you are running 200 amps
so 200 amps times 24v = 4800 watts , alot of power in a small scooter
were you to run a 72v motor , 72 volts at 200 amps you are now running 14,400 watts//
SO it all balances out , Until you decide to over volt the motor/. Because controllers for scooters are widely limited to 60 volts, its simply less effieicent to carry extra batteries to overvolt at a higher voltage.Ive tested it all , NO ONE in the history of this forum has build a powerhouse at higher voltage , the fastest karts and scooters were always below 48v .. this also ties into rpm per volt , or KV as they call it in rc motors.. a 24 v motor spinning at 3000 rpm is getting over 100 rpm per volt , a 72v motor spinning at 3000 rpm is getting less than 50 rpm per volt.. SO , if you wanted to gain 1500 rpm , which is easier to do ??? run the 72 v motor at 108volts , or simply run the 24 v motor at 36 v ?? ok im done . GO LOW VOLTAGE < it leaves you with more options .