Battery Diagnostics?

[rfc]

Been flying for over a year with three batteries purchased with my M2Pro. Recently, after a full charge on one of them, I took off; Battery showed 98 percent; within 1 minute, after a climb to 350', I got a bunch of warnings, the most notable of which was something like "Battery critical low warning; Landing". I immediately returned and landed without incident but it causes me considerable anguish.

Can a battery be properly diagnosed when in the machine? Is there another way to do diagnostics. I have noticed a slight bulging of all three of my batteries, and if one can only get a couple years out of a battery, I'm ready to dump them and replace with new; way cheaper than a new bird.

Advice most apprieciated.

 

[itsneedtokno]

Yes, using Airdata you can see the flight cycles, and I believe with the paid version you can see cell deviation and whatnot.


Somebody with an Airdata sub will chime in soon.

 

[itsneedtokno]

If you've been flying with same batteries for years, replace them now.

Swelling is never good.

And also, if you watch your cells during flight you may get a little advanced notice.


You could post the log from the flight you are talking about, but that's probably unnecessary.

Like I said, somebody else will chime in soon, these are just my two cents.

 

[bumper]

Search the posts here. At some point in time before I purchased my M2P in November of 19, there was a batch of bad batteries that suffered from early swelling. IIRC, DJI replaced those for free. It may be unlikely they would still do that, but it may be worth looking into.

 

[Thomas B]

Been flying for over a year with three batteries purchased with my M2Pro. Recently, after a full charge on one of them, I took off; Battery showed 98 percent; within 1 minute, after a climb to 350', I got a bunch of warnings, the most notable of which was something like "Battery critical low warning; Landing". I immediately returned and landed without incident but it causes me considerable anguish.

Can a battery be properly diagnosed when in the machine? Is there another way to do diagnostics. I have noticed a slight bulging of all three of my batteries, and if one can only get a couple years out of a battery, I'm ready to dump them and replace with new; way cheaper than a new bird.

Advice most apprieciated.

I had a battery fail in the same fashion with no swelling or other prior indication. I hover and fly close for a minute or so with every flight now. I have had no recurrences in my 9 other batteries after hundreds of flights on each.
Stay alert.

 

[rfc]

I took at the flight in question on AirData...I first got a warning: "Propulsion has been limited to protect battery health". Then a few seconds later, the battery went from 96 percent or so to 0, and that's when the "critical low battery...only enough battery to return to home...Landing" (or something like that). Ugh. Not good.

 

[Not A Speck Of Cereal]

It would be nice to have a tool that could do a ground-based stress test.

As itsneedtokno mentioned, you can monitor the 4 cells in real time on the Battery page of DJI Go. Perhaps some flight tests would indicate which batteries are starting to fail.

Bumper: yes, I think the date range is roughly late summer 2018 into the fall, and I believe they are still replacing them, though from some reports on these boards, you may need to push back when they at first say no.

 

[Thomas B]

See my post above. No swelling of battery before and no indication of a problem until I was airborne for about 30 seconds or so. It can occur unexpectedly and seems not to be sure evident until a load is applied.

 

[Not A Speck Of Cereal]

Yeah, but you could be talking about battery conditions in good batteries, where RFC might have batteries from the known-bad period. Both could be true, your experience and RFC's experience.

 

[rfc]

It would be nice to have a tool that could do a ground-based stress test.

As itsneedtokno mentioned, you can monitor the 4 cells in real time on the Battery page of DJI Go. Perhaps some flight tests would indicate which batteries are starting to fail.

Bumper: yes, I think the date range is roughly late summer 2018 into the fall, and I believe they are still replacing them, though from some reports on these boards, you may need to push back when they at first say no.

View attachment 113429

Yeah, but you could be talking about battery conditions in good batteries, where RFC might have batteries from the known-bad period. Both could be true, your experience and RFC's experience.

The battery in question was manufactured in 8/2018 and has 32 charges on it.

 

[Not A Speck Of Cereal]

The battery in question was manufactured in 8/2018 and has 32 charges on it.

Yeah, the only thing I would do before contacting DJI for a replacement, is to first check your other batteries for the same date-range and indication of problems (swelling, or cell abnormal cell deviations in DJI Go 4).

Chris

 

[rfc]

Yeah, the only thing I would do before contacting DJI for a replacement, is to first check your other batteries for the same date-range and indication of problems (swelling, or cell abnormal cell deviations in DJI Go 4).

Chris

Will do. Thank you.

 

[itsneedtokno]

View attachment 113429

What Hump?!

?

 

[WDKZoom]

Yes, using Airdata you can see the flight cycles, and I believe with the paid version you can see cell deviation and whatnot.


Somebody with an Airdata sub will chime in soon.

You don't have to pay for AirData to see Cell Deviation......I have a battery with 40 cycles showing cell deviation now and I am wondering if I should fly it as well.

WDK

 

[Otisangb]

Been flying for over a year with three batteries purchased with my M2Pro. Recently, after a full charge on one of them, I took off; Battery showed 98 percent; within 1 minute, after a climb to 350', I got a bunch of warnings, the most notable of which was something like "Battery critical low warning; Landing". I immediately returned and landed without incident but it causes me considerable anguish.

Can a battery be properly diagnosed when in the machine? Is there another way to do diagnostics. I have noticed a slight bulging of all three of my batteries, and if one can only get a couple years out of a battery, I'm ready to dump them and replace with new; way cheaper than a new bird.

Advice most apprieciated.

I have not seen or am aware of a built in load test for the batteries. It would be a nice featuee though. If i happen to break one of the battery charging cables i may use the battery cable connector an come up with an external static load/stress test. But i think you already found out about your dynamic load test. I would replace the swollen batteries.

 

[rfc]

Things might be looking up! After some back and forth with DJI, and submitting a video showing that the batteries power up the A/C, and showing the serial numbers of the batteries, they've asked me for my shipping address! Stay tuned.

 

[rfc]

Final report: DJI has come through for me. Received three new batteries today.They may have been acting out of fear of legal issues because batteries were involved, but no matter; I think they did the right thing.

 

[Marco Cantieni]

Somebody with an Airdata sub will chime in soon.

I have had the same experience with a capacity drop from 96% to 0% and a force landing. I then subscribed to AirData Gold to check cell deviations over time (not just for each flight separately) .

Below two screenshot from a good battery and a bad battery (the one described above).

Good Battery:



Bad Battery:



Conclusion: I've taken the bad battery out of service