It doesn't make a great deal of difference how you discharge them, just monitor the voltage and do not let them discharge below 1 volt/cell--4.4 volts for the reciever battery: 8.8 volts for the transmitter battery. The reason for that is so that you never reverse charge the weakest cell in the string which could cause permanent damage to that cell. Actually, if you could monitor each cell and never discharge to the point where one reverses polarity, no harm would be done even if some of the cells were discharged to zero volts; however that is impracticle to do so, to be safe, just stop the charge at 1 volt/cell and you will never reverse charge the weak cell and yet most of the energy will have been dumped from all cells. Do check out www.rcbatteryclinc.com for good valid info on the care of your batteries.