The discharger will stop discharging completely once the discharging is done. The discharger is also very easy to use. You just need to plug in the 1S battery and the red led should be on, which indicates the discharger is working. The red led indicator will be off once the discharging is completed. FYI: Please press the button on the discharger to put the discharger in working mode if the red LED indicator doesn’t turn on after the 1S battery is plugged in.