No. It is no longer recommended by DJI and certainly not necessary for the battery management SOC to update cell performance characteristics (this happens continuously during use and charging).Is total re-charging really necessary after every 20 charges?
Thanks - makes life simpler.No. It is no longer recommended by DJI and certainly not necessary for the battery management SOC to update cell performance characteristics (this happens continuously during use and charging).
I had a battery force me to land within 5 minutes with a "fatal battery error" warning. Recharging it as per normal gave the same result. A slow, deep discharge ie leave it on in the bird until it turns itself off and then a full charge fixed it.
A deep discharge may allow a balance issue to resolve during recharge (if that is the issue). With respect to the OP question the deep discharge provides no benefit whatsoever so far as calibration (including determining 0, 100 or any other %). The TI battery management SOC constantly measures and updates all critical parameters (including IR) during charge and discharge.Yes, if there is an actual issue, running the battery down to 8% can reset it so it knows what is "0% and what is 100%. But if there are no issues, it's not needed.
I'd also keep a _close_ eye on the battery as it could be a failing cell.
What would this "balancing" issue be that a deep discharge helps resolve?A deep discharge may allow a balance issue to resolve during recharge (if that is the issue).
That being the case and in the interest of addressing the OP’s question let’s qualify it by making it clear that a cell balance issue is rarely resolved by deep discharging the pack. A significant cell balance issue (70mv+ Is a conservative figure for our application in the phantoms) is usually a function of Individual cell IR values. Deep discharge cannot improve IR or recover lost capacity, all we might hope for is that the terminal voltage of the bad cell might be brought closer to the others during charging from a lower starting capacity (the smart board only has .25w bleed resistors for balancing). We may buy a little extra time before the bad cell approaches LVC by deep discharging. Reality is the pack is approaching retirement.What would this "balancing" issue be that a deep discharge helps resolve?
A "balance" issue is that one of the cells it not tracking correctly as to it's 0-100% charge state as it relates to the other cells. Basically, what I mentioned.
Yes, I have marked it accordingly & only use it for testing.Yes, if there is an actual issue, running the battery down to 8% can reset it so it knows what is "0% and what is 100%. But if there are no issues, it's not needed.
I'd also keep a _close_ eye on the battery as it could be a failing cell.
That is a helpful addition, the fact you retired it confirms that significant voltage differences between LiPo cells in a battery can’t be satisfactory resolved by any means, including deep discharge. You may recover a little capacity, perhaps the pack would be acceptable for an application with lower demands for current delivery, it can’t be trusted in a phantom or similar application though.Yes, I have marked it accordingly & only use it for testing.