Hello all,

I have found what seems to be a chronic and fatal issue with the DJI batteries for Mavic 2.
Please read the short summary below.

Two months ago I submitted a Mavic 2 Zoom to DJI Repair under warranty.  The aircraft lost power without warning and smashed into the ground.
Later while reviewing the logs, multiple battery errors (i2c core recovery! messages) had been recorded in the .DAT log during the entire flight.
The drone was finally replaced under warranty - but not the battery that had caused the issues.

With the replacement drone, the same scenario happened when using that battery that was not replaced.
Again I submitted a warranty repair for both the aircraft and the battery.




I am now with the second aircraft replaced under warranty.
When flying with one of my other batteries (Battery 1 below), I noticed something strange - the battery percentage and flight time remaining went blank on DJI Go 4.
I landed the aircraft immediately and took it inside.
I started the motors to take off on my carpet. Just as I was pushing up on the throttle, I again witnessed the Mavic 2 completely lose power.
The battery light was on, as if the battery was powered - but it was not functioning.  Luckily I was only inches off of my floor and there was no damage.
I investigated that battery, compared it with the others, and found some suprising results.



Note the appearance of the last four pins.  It appears the pins have recessed and the plastic around them has even slightly melted.



This battery is less than a year old and has less than 30 charges.
For comparison, here is a battery which does not show signs as bad as Battery 1.
Ironically this is my most beat-up battery and has over 150 charges.



Lastly, here are Batteries 3 and 4 which show the same problem, but not as bad as Battery 1.  I am not comfortable using any of these batteries.







I would like to hear what DJI thinks about this apparent design flaw in these batteries.
It is also possible that the first drone I submitted under warranty had damaged these batteries.
Finally, I would like to submit a warranty request for replacement for all three batteries which show this problem.

Please check these pins on your own batteries.  I don't think I could be the only one with this issue and you don't want to have your drone drop out of the sky like mine did - twice.

Hi Kazzaaz, I am sorry to read your issue. As per the picture of the batteries, the issue happens at the same place. May I know if the battery connectors on charger or charging hub are all looking well? Is it difficult when you tried to remove the battery from the charger? If so, you may send the charger and charging hub for diagnosis. Regarding the batteries, please don't continue flying with the issued batteries. If they are within the warranty period, please send them back for service.
Please fill out the online repair request on our official web and then send it back. Here is the link: https://repair.dji.com/repair/index
We will do our best to help this out.

Are you using an aftermarket charger? Maybe that damaged you batteries.

None of my 6 batteries show any issue after 100's of flights.
Propably not  a battery problem.I'd say your first drone had bad connecotrs and you failed to inspect even after a crash.
That's pilot error.

Dirty Bird Posted at 8-13 13:52
I examined my Mavic 2 packs & all are fine.  Pristine in fact.  Not sure what the initial cause of your contact problem may have been?  If the drone & batteries are being stored where there is high-humidity, that may have caused some corrosion leading to increased resistance & heat, & ultimately to your situation.   Usually battery contacts are gold-plated to prevent corrosion, & installing them typically does a bit of self cleaning.

Alternatively, perhaps they were exposed to something in the environment that was corrosive?  Frequent flights over the ocean, or flying through mist, fog, rain, or clouds?  Do you fly in these conditions?

I live in a pretty mild climate - and while I may have gone through some fog or a sprinkle of rain, I try to avoid these conditions and I am rather certain corrosion is not the cause since it is isolated to the last 4 pins in all cases.

Rather, I suspect the battery is producing an arcing current (spark) during discharge.

I concur with your hypothesis that the pins in my original drone were not making complete contact with the battery, which caused the arc and eroded the pins on the battery.  Once the battery pins were damaged, that battery would again fail to make complete contact and arc in a similar matter on a different drone.

DJI Susan Posted at 8-13 19:55
Hi Kazzaaz, I am sorry to read your issue. As per the picture of the batteries, the issue happens at the same place. May I know if the battery connectors on charger or charging hub are all looking well? Is it difficult when you tried to remove the battery from the charger? If so, you may send the charger and charging hub for diagnosis. Regarding the batteries, please don't continue flying with the issued batteries. If they are within the warranty period, please send them back for service.
Please fill out the online repair request on our official web and then send it back. Here is the link: https://repair.dji.com/repair/index
We will do our best to help this out.

Hi Susan,

Thanks for taking a look.
I am using three different single-battery DJI chargers and none of them show any signs of damage.
Should I send in the aircraft as well?  With the replies I have gotten on this topic I am now nervous the batteries could have again damaged the aircraft without my knowledge.

jcdonelson Posted at 8-14 05:05
None of my 6 batteries show any issue after 100's of flights.
Propably not  a battery problem.I'd say your first drone had bad connecotrs and you failed to inspect even after a crash.
That's pilot error.

That's pretty harsh.

I inspect my drone before each flight, check batteries for swelling, and make sure it is latched properly.
On Battery #1 that was partially melted, the damage is more noticeable and I am sure this happened during the last flight in which that battery was used.
For the others, the damage was not apparent until I compared the batteries side-by-side.

Clearly, pilot error is not the reason for the batteries ending up in this condition.
This is a manufacturing defect with either the batteries, or the first drone that had been damaging them.

Sorry to hear, Hope all go's well with warranty replacement for your batteries, thanks for sharing this issue and making me and others aware of this issue, not normally a pre-flight check, but will maybe check batteries and drone connections more often. Cheers.

Kazzaaz Posted at 8-14 07:06
Hi Susan,

Thanks for taking a look.

Yes, I‘d suggest sending the drone and batteries for diagnosis. Please start a case and send them in. Thank you.

DJI Susan Posted at 8-16 03:02
Yes, I‘d suggest sending the drone and batteries for diagnosis. Please start a case and send them in. Thank you.

Hi again Suzan,

I created a case and sent all 5 of my batteries along with the aircraft.
The case number is CAS-4837391-K8H8C7
Can you please monitor this case for me and ensure progress is made?  This summer has not been lucky for me and my drones but I am hoping after this warranty replacement I am hoping I will still have some good weather to fly in!

Kazzaaz Posted at 8-18 08:23
Hi again Suzan,

I created a case and sent all 5 of my batteries along with the aircraft.

I will keep an eye on the status. If further assistance is needed during the service, feel free to contact me at any time.

Hi all,

I am pleased to report I received today a full replacement of the aircraft and 5 batteries.
They are charging now and I can't wait to fly without anxiety
Thanks for the satisfactory customer service and warranty policy.