Does landing your mavic at <%10 nuke your battery?

[MavicFT1P]

Will it ever have %100 performance again, Yes or No?

 

[RayOZ]

I've done it with my old MP. I was doing a full cycle maintenance, not sure it was necessary. Usually I would have it powered on but motors off until battery is around 8%, then fully charge once cool. I won't never leave it for < 20% for long periods.
Anyway, it seems to have similar performance many cycles after that. I won't recommend flying with less than 20%. I was hovering it front of me from 15%. When it dropped to ~10%, I was amazed how fast the % starts to drop.

 

[WithTheBirds]

No.

 

[4wd]

It shouldn't have any negative effect and could even be beneficial provided you got it back up to near 50% ASAP.
Being left too low is not good for them same as being left full - but they can drop charge on their own from full after a few days - they need you to lift them if dangerously low.

Even if you ran it down to zero there is actually a safe charge left in, if you could run it down completely you might find it wouldn't do anything when put in the charger,
The less smart ones in the past would do this but you could set them off by linking in parallel with another battery.
Probably not wise to try that now.

 

[MavicFT1P]

I had a new battery recently. It performed excellently. I tried to keep it above %20 per the LIpo Rule (does that apply to Mavic), so I would have one Great battery for when i really needed to rely on it/get the most flight time.
But life happened
I landed very low battery, and in my rush to turn it off, did not turn it off properly (it was noisy), so it sat there running for another 2 mins while i was doing stuff. Went to pack it up and heard it humming >_<!!

Mobizen shows it went all the way to zero on the ground, plus about a minute.
I guesstimate it must have been minus %1 percent, but the low drain of the camera kept it on somehow.

So yeh, depsite only 4 charge cycles i worry ive nuked it
To be fair it charged up fine. but...First flight out with it next time i got discharge erros
I get them all the time with my other batteries when pinning, but until
this incident i had not gotten them with this battery' , and now its doing it like the others.

So thus my notion that landing below <%10 is very bad for battery,
At the very least, it takes away the "Polish" that new batteries have.. *shrug*

 

[Detritalgeo]

Every lithium ion pack has a max and min voltage with a unique discharge characteristic. This pack has 3 Lipo cells in series and generally expends the 28 Wh in 15-20 minutes so that is about 8 amps discharge rate at a nominal 11.5V.

Li-ion chemistry in general is perfectly fine between 3 and 4.2V, there are some specific "high-voltage" chemistry that prefer 3 - 4.35V. So the MA pack supplies 9 -12.6V so the 11.5V is nominal. It is very common for the last 10-15% of the voltage to drop quickly.

It is up to the battery management board to control the max voltage and min voltage cut-off as well as over-current cut-off protection. Without this the battery will drain below 2.5V and eventually to 0V and irreparable harm occurs. Even if you run the battery until it cuts off power it is generally still fine as it has been cut-off at the minimum voltage determined by the li-ion protection IC in the battery itself.

Bottom line is it won't hurt it. But if you don't re-charge to about 50% after it is at risk of falling below 2.5V by ambient discharge.. At this point the protection IC will not allow the cells to be charged again..

 

[MavicFT1P]

Thanks for that. I think/hope you are right.
At least one of my supposedly nuked batteries, performed excellently the other day. no batt errors.
Granted there was zero wind, whereas the flight before there was considerable.

Do you top up your batteries before flight? I have 2 or 3 day old %100 batteries that dont charge if plugged in, so
I find draining them to %98 percent and topping them up an hour (to let cool down) before flight ensures you have max capacity, nominal temperature.

 

[WithTheBirds]

Thanks for that. I think/hope you are right.
At least one of my supposedly nuked batteries, performed excellently the other day. no batt errors.
Granted there was zero wind, whereas the flight before there was considerable.

Do you top up your batteries before flight? I have 2 or 3 day old %100 batteries that dont charge if plugged in, so
I find draining them to %98 percent and topping them up an hour (to let cool down) before flight ensures you have max capacity, nominal temperature.

No need to drain them slightly to top off. A simpler solution is to turn them in before connecting the power.

 

[Detritalgeo]

The universal Li-ion charge pattern is CC-CV (constant current - constant voltage). The charge controller circuitry puts in a constant current at a defined max voltage (4.2V per cell or 12.6V for the 3s battery). I am guessing 1-2 amps. In this condition, the battery can gain charge quickly and it is why you hear often that batteries can be re-charge to 80% capacity quickly.

Once the pack reaches 4.2V per cell, the charging controller IC begins to reduce the current in an effort to keep the cells at that max voltage. This process is much slower as the charge current is reduced gradually, filling up the last 20%) until only a few mA "trickle" can be added while keeping it at 4.2 per cell.

It's hard to know exactly what the DJI charge controller is programmed to do. It is possible that the battery flashing only represents the CC phase..

 

[MavicFT1P]

Thats some battery knowledge/tech there.
One thing ive noticed is that when i do my slight decharge in to %98.
It takes a long time, Almost as long as %60 charge from 0. to go from 98 to 100
I assume this is because it does a 'Balance charge' each time.

No need to drain them slightly to top off. A simpler solution is to turn them in before connecting the power.

Doesn't work for me, Sometimes pressing the button gets it to recognize it's slightly below %100.

Is there a algorithm for how they decrease over the 10 days? As i mentioned Ive had battiers as much as 3 days old
that still register as Full.
Flying them, there is no doubt they have drained a little.

 

[WithTheBirds]

Thats some battery knowledge/tech there.
One thing ive noticed is that when i do my slight decharge in to %98.
It takes a long time, Almost as long as %60 charge from 0. to go from 98 to 100
I assume this is because it does a 'Balance charge' each time.



Doesn't work for me, Sometimes pressing the button gets it to recognize it's slightly below %100.

Is there a algorithm for how they decrease over the 10 days? As i mentioned Ive had battiers as much as 3 days old
that still register as Full.
Flying them, there is no doubt they have drained a little.

Not single press- turn it on before you connect it. There is an algorithm in the battery that will let it know your intention is to top off.

Hard to calculate exact depletion over 10 days.

The SOC uses a very small amount of power running the cell checking routines (yes even while turned off) and you also have a minimal self discharge with the chemistry which isn’t constant and does vary with age.

 

[Nitjt]

interesting

 

[GadgetGuy]

Not single press- turn it on before you connect it. There is an algorithm in the battery that will let it know your intention is to top off.

That old method unfortunately no longer works on M2 and P4 batteries. You have to drain them to 97% or below before the charger will let you top them off. Fortunately, the M2 battery USB charger adapter works relatively well for this purpose, if you top off your iPad with it first by turning it on, before finally topping off the M2 battery for flight. Another tip is to use a 50% storage mode battery to find the GPS satellites first, and then switch to a 100% battery for flight. This gives you the most flight time by starting at a full 100% at lift off.