Instructables

Variable 0V-24V, 0Amp-5Amp DC Battery Pack ?

I am building a portable battery pack of 21000 mAh and 25.9 Volts.
I need a circuit to vary its voltage from 0 volts to 24 volts, or maybe 1.25 volts to 24 volts and a circuit to vary its current from 0 Amps to 5 Amps.

Basically i need a Voltage and Current regulator.

for varying current, i was thinking of attaching a potentiometer in series with the output of battery. As the resistance would vary, the current will vary. Will it work?

Now i need something for varying voltage..