Damaged cell? or something internal in drone

[JasonCarignan]

On saturday i was doing some filming for a movie. It was cold outside. - 35 C
I kept my batteries in my inside jacket pocket until ready for use. I put the drone in the back seat of the warm car. Inserted the battery and fired the drone up. message came up - IMU is warming up, then safe to fly.
Sent the drone up and started filming. Another message pops up - Damaged cell warning! There was 30 seconds left for the scene so i kept the shot going. It was a total of 2 minutes. 30 seconds of that was with the damaged cell warning.
*The battery life was bad that day until about noon when the temp rose about 20 degrees. Luckily i had 3 batteries so there was always one on charge.*
Anyways I landed the craft and removed the battery and put it on the charger.
I inserted a new battery and started the next film shot. No warnings at first. Then a pop u on the DJI screen said that i was operating in cold weather below 0 C. That was it. This shot lasted about 5 minutes with extra takes.

Throughout the day i swapped between 3 batts as they charged.
Heres were it gets weird. I uploaded my flight records into healthy drones, to check my logs.
And in every single flight cell 1 is in the red with a deviation ranging from 0.070v - 0.098v
I can understand if it was just the 1 battery that had that. Hence the warning. But all 3 batteries recording a bad cell 1?
1 of the batteries was fresh FROM dji, out of the box and onto the charger.

So my question is, can there be an issue with the drones internals not accepting the full charge from cell 1 across all batteries?
Any suggestions would be greatly appreciated.

For reference:
DJI Phantom 3 Advanced
Using the DJI GO App.
Cold weather - 35 c to - 15 c
Total of 3 batteries being used. every flight record across all batts state cell 1 as deviation.

Ive flown in - 30c many times before with out any issues. I live in the canadas north. I use the drone mainly for aerial surveys with Pix4D to do volume calcs.
Sometimes i get contracted to do other aerial works, such as inspections or property photos
This being the first actual movie ive been hired to film, it was a lot of fun and looking forward to doing more of this type of work

 

[sonof40]

The only potential problem I see is recharging before cooling.

 

[JasonCarignan]

The only potential problem I see is recharging before cooling.

Is it possible the drones internals could be reading something wrong? It just seems odd that all 3 batteries are reporting the same cell as being damaged out of no where. I always do pre flight equipment checks before a job.
All 3 batts reported zero issue the night before. The only time they were exposed to the cold was when they were inside the drone.
I havent done a test flight since sat. Perhaps i should cycle flights with different batts and do a report on them?

 

[sonof40]

Is it possible the drones internals could be reading something wrong? It just seems odd that all 3 batteries are reporting the same cell as being damaged out of no where. I always do pre flight equipment checks before a job.
All 3 batts reported zero issue the night before. The only time they were exposed to the cold was when they were inside the drone.
I havent done a test flight since sat. Perhaps i should cycle flights with different batts and do a report on them?

I could be way wrong here but if you are recharging before a battery cools to "room temp" you might be affecting each battery in the same destructive way. Maybe one cell gets hotter than the others depending on its proximity in the bird.

 

[JasonCarignan]

Oh absolutely. I actually attempted that once. But the battery wouldnt let me charge it. It just flashed with an error. That was the first time i tried charging it though - about 4 months ago now
I got the drone on, and im watching the battery outputs in the dji app, and its showing everything as good across all batteries.
Im starting to think it was something to do with the drones "Smart Internals" reading a false positive. And for some reason imprinting that across all flight records.
Or does that seem far fetched lol

 

[Mark The Droner]

Minus 35C is pretty friggin' cold. I wouldn't draw any conclusions until you can test them again at more reasonable temps.

 

[N017RW]

0 - 40C is the published operating spec.

Phantom 3 Professional - Specs, FAQ, Tutorials, Downloads and DJI GO | DJI

 

[Oso]

Wow, that's cold. I wouldn't be surprised if DJI would love to see the flight data.

I'd have to think it's related to the cold and that it's not your drone's internals. I think you'll need to find a better way to keep your batteries warm, and even then it would be hit or miss if they would work reliably in those weather conditions. As noted, per DJI you were far below their listed safe range.

Healthy Drones is useful to an extent, but it is known for frequently showing cell 1 in the red. The author picked a number to use as the trigger for a major deviation. As he was working on it, he would even take advice from members here on changes to the settings for different things. He is the one who assigned when a cell shows red or not.

Healthy Drones does provide interesting data and I use it myself to possibly highlight something to watch for, but I personally assign much more weight to what DJI tells me either through the app or other documentation. If the app tells me the cells are green, I trust it more than Health Drones. Same as when the app shows me if cells are yellow, etc.

With that in mind, I would have probably landed if I had the warnings you saw in the app. I would have found it too risky to have my Phantom in the air if the app were telling me that there was cell damage. I'm happy it happened to work out for you this time.

 

[Sagebrush]

I'd be curious as to what the condition looks like with the Phantom fired up inside. -35ºC? Ouch. That has to be a factor.

S

 

[JasonCarignan]

Well interesting development. I viewed each battery in the DJI app and each cell is in the green across all batteries.
Not a dang thing out of the ordinary. Im going to be sending it up shortly once a guest arrives. If all goes well, it wont fall out of the sky. Thank you guys for pointing out to not take healthydrones readings as gospel.
Each battery fully charged ( App is saying 98%) is reading each cell at 4.28V - 4.29V