Hi all..

I could use some advise here.. I haven't flow my drone for a while and kinda forgot the safe and seperately stored batteries. Assuming they would unload to a battery-safe level after 2 days as setup in the RC i found out that only two of the three batteries really unloaded to a safe level. The third battery still had like a 70/75% load and an extra message when starting up the system... battery error :-]   

I'm trying if it is posible to re-balance the cells doing several load/unload cycles. DJI's advice that can be read in the warning.. and I'm still in that process.

Looking in the djigo app there is a difference in voltage between the seperate cells off around 0.05v and 0.09v during a my first stationary take-off drone unload cycle. Once in a while i revved up the speed of the propellors just enough not to take off indoor ;-) hoping to speed up the unloading process. In one of these events,  thunder with a blue sky,  the engines cut off.  The battery, although with a cell error, still was 60%... but it made me wonder if it is safe using this battery in the future?

Is it possible to rebalance the battery with load/unload/ reset(as in refresh firmware with DJIassistant) cycles?   How reliable is this method?  If it even works........

Would love to hear your experts experience/advise..

ps battery has 33 loadcycles 1.5 year old

My sincere apologies for the inconvenience that it caused. If an Intelligent Battery has been stored for an extended period, but it has not been charged and discharged, its protection board cannot balance the battery’s cells sufficiently to avoid a significant voltage difference. When the voltage difference exceeds the safe threshold, the battery’s cells will become damaged. To avoid this, we recommend that you discharge the battery to 40% to 65% of its total power and store it in a cool, dry space (at an ambient temperature of 22°C to 28°C) when it is going to be idle for more than 10 days. Check the battery’s power every three months and fully charge and discharge it at least once. Please perform routine maintenance to keep your battery healthy. By the way, may I know if you tried to discharge the battery and then fully charge it after? When did you purchase it for me to check the warranty? Appreciate your support.

DJI Paladin Posted at 5-2 08:24
My sincere apologies for the inconvenience that it caused. If an Intelligent Battery has been stored for an extended period, but it has not been charged and discharged, its protection board cannot balance the battery’s cells sufficiently to avoid a significant voltage difference. When the voltage difference exceeds the safe threshold, the battery’s cells will become damaged. To avoid this, we recommend that you discharge the battery to 40% to 65% of its total power and store it in a cool, dry space (at an ambient temperature of 22°C to 28°C) when it is going to be idle for more than 10 days. Check the battery’s power every three months and fully charge and discharge it at least once. Please perform routine maintenance to keep your battery healthy. By the way, may I know if you tried to discharge the battery and then fully charge it after? When did you purchase it for me to check the warranty? Appreciate your support.

thx  
in reply to your question... battery if from end 2016... bought the fly more set in may 2017 .. so understandable  no more warrenty ...

anyway  it's weird the battery didn't start its unload cycle  during the period i was not using it...   
Let me know if you want it back for R&D...

DJI Paladin Posted at 5-2 08:24
My sincere apologies for the inconvenience that it caused. If an Intelligent Battery has been stored for an extended period, but it has not been charged and discharged, its protection board cannot balance the battery’s cells sufficiently to avoid a significant voltage difference. When the voltage difference exceeds the safe threshold, the battery’s cells will become damaged. To avoid this, we recommend that you discharge the battery to 40% to 65% of its total power and store it in a cool, dry space (at an ambient temperature of 22°C to 28°C) when it is going to be idle for more than 10 days. Check the battery’s power every three months and fully charge and discharge it at least once. Please perform routine maintenance to keep your battery healthy. By the way, may I know if you tried to discharge the battery and then fully charge it after? When did you purchase it for me to check the warranty? Appreciate your support.

I've loaded and unloade the battery now three times... and until now it still gives a battery error...
While unloading it at approx 50% the battery error dissapeared... so i was able to start the drone...

seems like a sweet spot where all cells are equally loaded/unloaded.......treid a 4th load cycle with the battery at 50% but it also resulted  when full in a batteru=y error..

it's difficult to fool these smart batteries ;-)