It has happend to all of us... get all charged up and ready to go and something happens... either weather or breakage; then we have full or nearly full batteries that need to be discharged to storage voltage.
Most decent chargers can handle this function, but the extra wear and tear (also known as heat) is hard on them... I would rather build/buy a cheap discharger than to replace a $150+ charger because it is wore out from discharging packs.
I would need one that can handle anything from 2S on up to 6S... and for it to be able to discharge something as small as 1800mAh all the way up to 9000mAh+; but all in a decent time without over-stressing the pack.
I would consider 45 minuets to an hour a decent time for my 7600mAh packs.
My thoughts so far... at least the ones I like... are to have selectable loads; where switches are flipped for 2S to go to a certain load bank, but additional switches expand the load bank for each cell count.
I have thought of using either bulbs or resistors... with only fan or fan and water cooling.
I have read a few builds, one of which had a cell log with alarm built into it so each cell was monitored as voltage was brought down. I like the idea... but I do not like that it only does one pack at a time as all of my RC's take 2 batteries minimum.
So what are your thoughts??
Whatever it is I just typed... could be wrong.