Battery cell deviation question

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I've got a P3P battery with about 34 charges, no drops, always taken down to about 30% before charging, but auto discharged about 4-times, which is now showing a deviation on cell #1. (100% charged, #1 at 4.24, the rest at 4.30)

I'm watching it carefully and haven't used it for anything critical over the last two flights after discovering the deviation on a Healthy Drones report, but I'm worried.

Should I be and if so what can be done to correct it?
 
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I would put it in the drone and run the battery down to 8%. Then do a full charge after that. You can run the battery down by flying...hovering...or just turning on the drone and running the lights. Then see if that makes a difference in the number of deviations you get for that cell. I have some on one of my battery's but the number of them are still pretty low according to healthy drones.

Sent from my SM-G900V using PhantomPilots mobile app
 
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I would put it in the drone and run the battery down to 8%. Then do a full charge after that. You can run the battery down by flying...hovering...or just turning on the drone and running the lights. Then see if that makes a difference in the number of deviations you get for that cell. I have some on one of my battery's but the number of them are still pretty low according to healthy drones.

Sent from my SM-G900V using PhantomPilots mobile app

I did that. Same deviations exist, didn't seem to make a difference. Battery charges fully, just seems to be off on that one cell.
 

Mark The Droner

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Healthy drones uses the 70 mv threshold to determine if there is a balance problem. And even if there is an occasional spike over 70 mv, it's not necessarily a problem. Since yours is only a 60 mv difference, it may be nothing to worry about.
 
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Oso

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I've got a P3P battery with about 34 charges, no drops, always taken down to about 30% before charging, but auto discharged about 4-times, which is now showing a deviation on cell #1. (100% charged, #1 at 4.24, the rest at 4.30)

I'm watching it carefully and haven't used it for anything critical over the last two flights after discovering the deviation on a Healthy Drones report, but I'm worried.

Should I be and if so what can be done to correct it?
Healthy Drones is useful to an extent, but it has been noted here on the forum many times that it frequently shows cell 1 deviations. The author (Eran Steiner) picked numbers to use as the trigger for reporting major or minor deviations. As he was working on writing the original code, he took advice from members here on changes to the settings for different things, and even changed the major deviation setting a time or two. He is the one who assigned triggers for when a cell shows a deviation or not, and his choice of voltage deviation is not agreed upon universally by the community.

Healthy Drones does provide interesting data and I use it myself to possibly highlight something to potentially watch for such as cell imbalance, 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 much more than Healthy Drones. Same as when the app shows me if cells are yellow, etc. If the app showed some abnormality, then I would be concerned.

All that being said, you mentioned that you are worried. That also carries a lot of weight. When you fly, you need to feel 100% percent confident in your equipment. That has a different meaning for every individual. If this battery causes you to be less than 100% confident, you should replace it and only use equipment that makes you feel 100% confident. As @Mark The Droner noted however, your deviation is relatively small. If it were my battery, I probably wouldn't even give it another thought.
 
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Healthy Drones is useful to an extent, but it has been noted here on the forum many times that it frequently shows cell 1 deviations. The author (Eran Steiner) picked numbers to use as the trigger for reporting major or minor deviations. As he was working on writing the original code, he took advice from members here on changes to the settings for different things, and even changed the major deviation setting a time or two. He is the one who assigned triggers for when a cell shows a deviation or not, and his choice of voltage deviation is not agreed upon universally by the community.

Healthy Drones does provide interesting data and I use it myself to possibly highlight something to potentially watch for such as cell imbalance, 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 much more than Healthy Drones. Same as when the app shows me if cells are yellow, etc. If the app showed some abnormality, then I would be concerned.

All that being said, you mentioned that you are worried. That also carries a lot of weight. When you fly, you need to feel 100% percent confident in your equipment. That has a different meaning for every individual. If this battery causes you to be less than 100% confident, you should replace it and only use equipment that makes you feel 100% confident. As @Mark The Droner noted however, your deviation is relatively small. If it were my battery, I probably wouldn't even give it another thought.
Thanks! This and Mark's response are both very helpful.

'DJI Go' shows all cells green, and there are never any warnings during flight, so I'm more confident that the cell dev seems to be normal 'wear and tear' for this battery's age. I'll keep a close eye on it with the intention of possibly replacing it soon.
 

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