Battery Balance

[Nemo5632]

Hey all, the attachment shows the battery balance I have at the moment.

I did have a error that stated battery error land. As soon as I powered up the mavic with this battery. The imbalance was worse that this, I have dropped the battery to 4% let cool then a full charge. Seems to have improved the imbalance, and now the error has gone.

Do you think repeating the step will fully correct? And would you fly with this battery?

I'm due on go to New Zealand soon and don't fully trust this battery, could it just die and fall from the sky?

Also thoughts on the best way to fully discharge? ( I lost the usb adaptor so can't do it that way) I was thinking take off the blades and leave in take off mode.

Thanks
Stu

 

[Kilrah]

I would repeat the cycle once or twice. Once balance is correct fly it close in while watching this screen, if one cell is still obviously lower at anytime down to reasonable landing levels (20%) RMA the batt.

 

[go fast]

Noticed your low battery warning is 15% I like to keep it at 30% , lipo's don't like to continually be run down too low just my observation...

 

[Blacksails]

If my experience with the Inspire has taught me anything, it's that DJI's intelligent batteries aren't that intelligent. They're smart in that they start to discharge after a set time to stop people who haven't dealt with lipos before from damaging the cells, but their balancing isn't the best.

The cells balance at the end of the charge cycle, but it seems after a while they still start to slip out.

I remove the top from my Inspire packs, remove the intelligent board and hook my cellpro 8 charger to the balance port inside the packs via a small df13-7 connector I wired up. I do this every time I start to see a worrying amount of imbalance and it always puts the packs right. The packs are fine, internal resistance of each cell (one of the best health indicators) is always good, the inbuilt balancing just isn't that smart.

I have never done the total discharge-charge "calibration" procedure that DJI recommends as I tend to watch cell voltage when flying rather than remaining flight time, and don't like trusting the packs low voltage cut off to prevent discharging too far.

I haven't had to do this on the mavic packs yet as I've only had the mav about 3 weeks now but expect that I will do in the future.

 

[Nemo5632]

Noticed your low battery warning is 15% I like to keep it at 30% , lipo's don't like to continually be run down too low just my observation...

Thats only done when I discharge the cell. Normally it's on default 30%