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Battery charge cycle counter

You need to use up about 80% points to clock the counter up by one. So a brand new battery at 100% will have a count of 0. Fly it until its down to 20% or less and then the counter inside the battery will increment to 1, but you'll not see this in the app until you've switched off then on again, and hence made the app read the current counter value, ie 1.

Flying a new batter down to 50% won't be enough to increment the counter.

The charge counter is essentially the number of times the battery has been drained by 80%. If you run your battery from 100% right down to 0% and the charge back up to 100% every time then the counter will soon show a higher number of cycles than what you've actually done, but would still be a reasonable reflection of the battery health.
 
Then that would mean that every time you turn on your battery and controller for a brand new flight it would count, you fly a mission starting at 100% fly down to 50%, have to land because of the wind or whatever and shut everything down to wait. The wind dies and you start up again at 50% with a plus 1 count.....you fly to 30% and again the the wind. You shut everything down and at 30% you take off again one more pic with yet again a plus one count....add to that you bring it home and hear about an update so you turn it on to download and you just triggered another count...this is what I think would happen but it’s not suppose to work that way. You just added three counts too your battery from 1 charge.

WDK
The counter is incremented by the TI chip which is inside the BMS. The BMS provides this information to the Mini which sets it into the telemetry.
 
You need to use up about 80% points to clock the counter up by one. So a brand new battery at 100% will have a count of 0. Fly it until its down to 20% or less and then the counter inside the battery will increment to 1, but you'll not see this in the app until you've switched off then on again, and hence made the app read the current counter value, ie 1.

Flying a new batter down to 50% won't be enough to increment the counter.

The charge counter is essentially the number of times the battery has been drained by 80%. If you run your battery from 100% right down to 0% and the charge back up to 100% every time then the counter will soon show a higher number of cycles than what you've actually done, but would still be a reasonable reflection of the battery health.

Thank you for your insight.....I am not ready to put my batteries up for a test understanding all that you have said but at best I am still skeptical as on several occasions of the 4 months I have been flying my zoom, I have had counts triggered after shutting my system down and as in the example I gave such as a depleted battery, 25% (which is what I always land at) to tweak my settings or looking for updates because I want to use a full charge to fly rather than tweak, I have always triggered counts and found it frustrating as I want to keep my batts on the same count so I have to play catch up with the other two keeping the one I used to tweak with out of the line up until I do.

WDK

WDK
 
25% (which is what I always land at)

Correct, DJI batteries cycle count accumulative charge is preset to 75% at the factory.
You could read the thread from the beginning to understand how counter works, especially this post.
So flying down to 25% is enough to increment the counter internally. It does not matter how much you switch the drone On and Off, because it's not drone's business to count cycles. It's special battery-side Fuel Gauge IC which cares about it. The Drone only read the value from the battery and sends to the app.
 
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I used 80% in my examples earlier, but just as a number to use. The exact value is configurable in the counter firmware and DJI have probably set this to 75% as per what everBit says.
 
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Correct, DJI batteries cycle count accumulative charge is preset to 75% at the factory.
You could read the thread from the beginning to understand how counter works, especially this post.
So flying down to 25% is enough to increment the counter internally. It does not matter how much you switch the drone On and Off, because it's not drone's business to count cycles. It's special battery-side Fuel Gauge IC which cares about it. The Drone only read the value from the battery and sends to the app.

I think you are missing what I am trying to say.. or I missing what you are trying to say...at 25% If I turn it on and off 4 times the battery will have counted each one of those before I charge it. If I land at 25% with the counter at 20, turn it on and off 4 times changing my settings etc the counter will read 24 and then if I charge it back to 100% the counter reads 25 when it should have only been 21. You are telling me that it should not have counted until the 100% charge but it has. I only charged it once but each time I turned it on, it counted those also.

WDK
 
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I think you are missing what I am trying to say.. or I missing what you are trying to say...at 25% If I turn it on and off 4 times the battery will have counted each one of those before I charge it. If I land at 25% with the counter at 20, turn it on and off 4 times changing my settings etc the counter will read 24 and then if I charge it back to 100% the counter reads 25 when it should have only been 21. You are telling me that it should not have counted until the 100% charge but it has. I only charged it once but each time I turned it on, it counted those also.

WDK
Ah OK, this is weird and I agree with your example it should stay at 21 ...
Nevertheless, I don't know if those counters are used by the BMS to determine the batt cannot fly anymore. I hope not ;-)
 
Ah OK, this is weird and I agree with your example it should stay at 21 ...
Nevertheless, I don't know if those counters are used by the BMS to determine the batt cannot fly anymore. I hope not ;-)

Oh, do the smart batteries have a number limit?? While I do keep the count, I also watch all the other stats as well. Right now my low voltage is 3.6 and I can fly at 100% for about 21 minutes....I thought when that time gets down to about 15 minutes it’s time to retire that battery.

WDK
 
That's strange behaviour for a charge cycle counter. Does it increment for any power off/on cycle? Or only once you've discharged a battery from 100% down to 25% or less and keep that battery in the drone? Perhaps there's a bug in the battery firmware where instead of just incrementing by 1 once it has discharged by 75% it gets stuck in an increment mode and keeps incrementing +1 every power off/on cycle until it is recharged and put out of increment mode?
 
That's strange behaviour for a charge cycle counter. Does it increment for any power off/on cycle? Or only once you've discharged a battery from 100% down to 25% or less and keep that battery in the drone? Perhaps there's a bug in the battery firmware where instead of just incrementing by 1 once it has discharged by 75% it gets stuck in an increment mode and keeps incrementing +1 every power off/on cycle until it is recharged and put out of increment mode?

The questions you ask are what I was trying to find out. I have read on several occasions that the count is only suppose to increment when the battery reaches a charge of 80% or more but I have found that not to be true with my set up.
I only do this when my battery count is not the same. I don’t want to experiment with my batteries, drone and and controller to see if I can continue the count like this but I have done on at least 5 occasions.

WDK
 
Oh, do the smart batteries have a number limit?? While I do keep the count, I also watch all the other stats as well. Right now my low voltage is 3.6 and I can fly at 100% for about 21 minutes....I thought when that time gets down to about 15 minutes it’s time to retire that battery.

WDK
I am not sure the cycle count is used by the smart battery to perform anything but user's information.
Reading a smart batt datasheet you can see:
[CCT]: This flag provides an option to use FullChargeCapacity() ([CCT] = 1) or DesignCapacity() ([CCT] =
0) for cycle count threshold calculation. If FullChargeCapacity() is selected for cycle count threshold
calculation, the minimum cycle count threshold is always 10% of Design Capacity. This is to avoid any
erroneous cycle count increment caused by extremely low FullChargeCapacity().

I understand this as you can go as low as a batt worn down to 10% of design capacity for its fullcharge capacity and the cyclecount will be incremented each time it reaches 10% of design capacity... Elsewhere we see that tha max cyclecount is 65535 (16 bits integer) that would give us some margins ;-)..
 
I am not sure the cycle count is used by the smart battery to perform anything but user's information.
Reading a smart batt datasheet you can see:
[CCT]: This flag provides an option to use FullChargeCapacity() ([CCT] = 1) or DesignCapacity() ([CCT] =
0) for cycle count threshold calculation. If FullChargeCapacity() is selected for cycle count threshold
calculation, the minimum cycle count threshold is always 10% of Design Capacity. This is to avoid any
erroneous cycle count increment caused by extremely low FullChargeCapacity().

I understand this as you can go as low as a batt worn down to 10% of design capacity for its fullcharge capacity and the cyclecount will be incremented each time it reaches 10% of design capacity... Elsewhere we see that tha max cyclecount is 65535 (16 bits integer) that would give us some margins ;-)..

Thank you....to be clear though, when I said “I thought” I was not referring to something I read or found out, it was just me saying that when or if my batteries get down to where I am only getting 15 minutes in the air out of them or when the voltage goes below 3.6 then personally, it’s time for me to buy new ones.

WDK
 
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