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BrianG · 10.17.2007, 11:27 AM

Oh, so it sounds like this zip charger is relying on the resistance from a long and smaller gauge wire to limit the current.

A better way would be to build a simple constant-current source using a high current transistor like a 2N3055 or similar. You'd still have to monitor the voltage (or add other circuits to do the cutoff), but this setup can be made to have an adjustable and constant current.

You could also use a regular NiMH charger since those are CC chargers. Still have to monitor the voltage.

When charging A123's, does the voltage dip at all at the end of the charge? If so, you could set the delta peak value of a NiMH charger to a really small value...

	(#28)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	10.17.2007, 11:27 AM Oh, so it sounds like this zip charger is relying on the resistance from a long and smaller gauge wire to limit the current. A better way would be to build a simple constant-current source using a high current transistor like a 2N3055 or similar. You'd still have to monitor the voltage (or add other circuits to do the cutoff), but this setup can be made to have an adjustable and constant current. You could also use a regular NiMH charger since those are CC chargers. Still have to monitor the voltage. When charging A123's, does the voltage dip at all at the end of the charge? If so, you could set the delta peak value of a NiMH charger to a really small value...