Been seeing some issues with a battery. Getting these voltage issues pictured. Has 91 charges on it and performs fine that I can tell. Any thoughts on these errors?
Battery Issue
- Thread starter bkushner
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What else does airdata report with respect to the battery....? Recorded capacity? Life %? Est flight time? What was the temp at launch (reported by battery and ambient)?Been seeing some issues with a battery. Getting these voltage issues pictured. Has 91 charges on it and performs fine that I can tell. Any thoughts on these errors?
91% Life 96 charges - Min temp 62 max 122 - I have 6 batteries and flew others this day with no error and this battery is now throwing those errors on that cell every flight. Flight time seems to be normal compared to other batteries. I guess my main question is should I stop using the battery?
Assuming it is an OEM battery, I would contact DJI and ABSOLUTELY stop using it. No battery is worth losing a bird for. Especially since you have five extras. Don’t risk it.
I would just write the battery off then. Don’t risk losing your bird over a $150 battery. Certainly not worth it.
Good luck.
alokbhargava
Premium Pilot
I suggest to deep discharge the battery to about 3-4% and charge back to 100%. See if it recovers.
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Looks like maybe one of the cells is on the way out.
The warnings are probably to do with an unbalanced pack with the one cell having a slightly divergent voltage. This means the "duff" cell will be working the hardest and might crap out on you quite soon.
Having said that, its only about 70mv difference, but I think the drone warns you if its above 40mv.
Keep an eye on it and if it continues to diverge just retire the pack and use it only for ground use.
There is no redundancy in the packs, they are 4 lipo cells in series and if one cell dies and goes open circuit the entire pack dies.
When in use, the low voltage cell will be forcibly charged by the other 3 cells in the pack until the voltage becomes equal, thats why balanced packs are important. In reality, a 70mv difference isnt very much but because it is flight critical the drone warns you early.
They should really be 8 cell batteries with two series banks of 4 in parallel, that way one duff cell wont bring the drone down.
If it did fail then you would lose half your capacity instantly but still be able to fly, rather than the battery potentially just dying on you mid flight which is what happens at the moment....
The warnings are probably to do with an unbalanced pack with the one cell having a slightly divergent voltage. This means the "duff" cell will be working the hardest and might crap out on you quite soon.
Having said that, its only about 70mv difference, but I think the drone warns you if its above 40mv.
Keep an eye on it and if it continues to diverge just retire the pack and use it only for ground use.
There is no redundancy in the packs, they are 4 lipo cells in series and if one cell dies and goes open circuit the entire pack dies.
When in use, the low voltage cell will be forcibly charged by the other 3 cells in the pack until the voltage becomes equal, thats why balanced packs are important. In reality, a 70mv difference isnt very much but because it is flight critical the drone warns you early.
They should really be 8 cell batteries with two series banks of 4 in parallel, that way one duff cell wont bring the drone down.
If it did fail then you would lose half your capacity instantly but still be able to fly, rather than the battery potentially just dying on you mid flight which is what happens at the moment....
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I've never seen a cell suddenly die and go open circuit, you shouldn't fear that.
What is something to fear is one cell going eroding too fast, deviating rapidly under load, especially in cold weather. You can monitor that if you want to continue using it, which I deem fairly safe for now, unless something changes. I wouldn't send that battery on long missions anymore, or missions over water.
What I would do is put a special red tag on the battery and use it less than the others, since it's higher risk. If you fly it, you'll need to monitor that cell. The voltage displayed in the upper right corner (if you have enabled the battery voltage to display) of the Go4 app is the voltage of your weakest cell, and in this case that would be cell #4. If it ever gets close to 3.2V at the end of a flight, I would retire it. Never fly this battery in super cold weather, as a marginal battery can decrease momentarily in voltage more rapidly than in pleasant weather. If the weakest cell ever hits 2.99V, the motors will shut down mid-flight, that's why you want to retire a battery with a huge deviation. Right now I would classify this as a mild deviation, one to watch going forward if you need to fly with it.
You might see an improvement if you deep cycled the battery, but generally speaking that doesn't work most the time.
I'm in the process of recharging after a taking the battery to 2%. Ironically no errors on the two flights I made with the battery to drain but I was just moseying along. I will keep eye on it..thanks for the reply.
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I had the same issue. About as many red cell errors as bkushner. Odd thing is this has been happening for a while getting worse then on my last flight, I had only 2 of red errors but on different cells. I think its because at that flight I didn't push it to max speed. I did chance it the other day pushing it when the voltage reading was turning red, even at 15% battery I went full throttle, and had red battery indication and red voltage warning. Curiosity got the better of me... "Will it cut out"? I went full throttle. Landed at 11% and no issues. But that was a one of risk. Been having bad batteries since last year. But I will order more and use the bad battery purely for firmware updates or just to warm the drone up when I first turn it on.
Just out of curiosity, do you use a multi charger for your batteries? I'm not sure if that's what is causing the cells to die.
Just out of curiosity, do you use a multi charger for your batteries? I'm not sure if that's what is causing the cells to die.
I have a multi charger but only use in a pinch. Normally I do one at a time via the DJI charger. Also I have 5 total batteries that I rotate and not seeing the error in any other.
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I have a feeling the multi charger is causing the issue. I use the 5 in 1 where it can charge up all 4 batteries and a charger all at once rather then one by one. Wondering if its sending the wrong voltage to the cells killing them off
Not likely. the battery has internal protection for over voltage and other power supply issues.
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Just really odd as why there are so many. Its like that on both batteries time to time. Around 86 charges on both. Over all life span is 82% and 86% so the cells shouldn't be that bad should it?
The question is how bad is bad? Airdata flags deviations red at 70mv. That is a conservative figure when the cells are heavily loaded (standard Neon flight style) in cooler temps and higher cycle count.
If your getting close to spec flight times and no warnings in the GO app you can be reasonably comfortable.
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Thanks W. T. B to be honest I get nothing on screen about voltage or battery warnings. And I do get standard flight times (about 16 mins before I land around 30%) I only get the voltage turning from green, yellow then red. From now on I will just fly at a casual speed (not full throttle) and try to keep the voltage in green at all times, as soon as it goes yellow I will slow down. Sometimes it can go from green to red, but I think that's me pushing it fast catching wind towards the drone. I still have no idea on voltage numbers. Is there a simple link you could paste to explain?
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