[ohio]

if i put 1 of these on each of my batts 13 of them do you think it worth it ?




http://cgi.ebay.com/ebaymotors/NEW-P...QQcmdZViewItem

[Mr. Sharkey]

What, exactly, do you expect it to do?

[CPLTECH]

One of the purposes of a capacitor is to merely "store" voltage. In electronics, it is used to smooth out the DC peaks & valleys of a power supply & mimic a battery in smoothness. The voltage quickly decays when input power is removed, as when batteries removed from a playing radio. I understand that a 50F must be "huge", but consider the "huge" amp draw of your motor. Explain any benefit in using the capacitor in this application.

[ohio]

faster take off and easier on the batts

[mattW]

The capacitors will only kick in when the voltage across the batteries drops and only until the charge held in them is dissipated. Those capacitors on a 12V battery could store 3600J each of energy, the rate of discharge is dependant on the change in voltage according to the equation i= Cdv/dt so current is equal to the capacitance (50F) times the rate of change of voltage (or the gradient of the voltage curve). You should whack a voltage meter across the terminals of you batteries and see if the voltage changes under take off etc.

[mattW]

If i was very clever and was willing to experiment i would have a relay which when the brake pedal was applied would disconnect the motor from the controller and connect it to the string of capacitors with a resistor to regulate it. They would then charge up pretty quickly while slowing the car down. Then once braking stopped i would have another relay(s) that would open and allow the capacitors to slowly discharge into the batteries. This would be a very efficient way to do regenerative breaking. If I was going to use capacitors that would be a much better use.