I find it very crazy that there is not a DJI produced accessories out there to help deep cycle batteries. They are asking use to fly our basically down to the batteries limits. On many levels I am not a fan of the technique. One is adding useless flight time on the aircraft, where you are putting more time on the motors, FC, Camera - which already runs hot, internal cooling fans, etc. If i wanted to take the all the gas out of a Cessna with 20% gas in the tank I would not sit on the runway and run the motor until it shut off The second thing is on the battery itself, you are taxing it down to its limits, I am not sure if you have felt the batteries after you fly it down to 5%, the are usually fairly hot, above 50 degrees Celsius (125F) by touch I feel they are much hotter then that. Why is it they have not come up with a small device that you can use to draw the proper safe voltage down until it shuts off. I would purchase that, considering I have five batteries. Right now the best technique I have found is to do some flight an then run a battery down to about the 5%, at that point you use it to recharge the controller, In most cases it will lower itself to the shut off point. Recently i have seen a few off market discharge device out there, but why has DJI not taken care of this, It puzzles me, why they have not done anything to help in this situation.