Average flight time with stock batteries ?

[Cookaboorra]

Hello everyone here !
I just bought a - used - Pro and after some time modded it.
I can fly it after a good charge for both batteries, an average 15 minutes before it drops quickly towards 8 % 4%.
I could see through Airdata ( what an amazing software.. ) that one cell in every battery drops a little faster than the others today having reached the 0,07 limit, red flag, fo the first time, @ 16 minutes of activity.
Well, I ask you, do you think it is normal ? I also have heavier carbon props installed...
Thank you

 

[slup]

Don't have a clue about your mods & how they might affect the flight times ... neither anything about the health status of the batteries you use ...

But looking at the specs & what DJI claim below, I would say that the times you get is somewhat 5-6min. short compared to a new battery.

 

[Crash-a-lot]

I think any weight added above the original drones weight will affect the flight time to some degree.

 

[Cookaboorra]

Don't have a clue about your mods & how they might affect the flight times ... neither anything about the health status of the batteries you use ...

But looking at the specs & what DJI claim below, I would say that the times you get is somewhat 5-6min. short compared to a new battery.

View attachment 125324

Thank You.
I needed some real world advice before freaking out in " the probs area ".
Both them have probably been left uncharged for many months.
The 5% level is reached after 15 minutes of normal mode flight, dropping from 10% rather quickly.
I'll continue flying this way, I will enjoy mountain exploring 5 minutes less each time !!!!

 

[old man mavic]

@Cookaboorra the problem you are encountering has two sources,one is the batteries themselves and the other is the CF props you are using,both these factors will reduce your airtime,and finally you are not helping your cause by running your batteries down to such low voltages as the battery goes below 25% then the cells struggle to deliver enough current ,this causes them to get even hotter and stresses the cells even more ,you will never achieve the stated flight times in real world situations due to the many outside factors that are present when you fly

 

[Flycaster]

Aside from the aftermarket props, you should look into the cycle count and health of the batteries. I suspect they may have given their best in the time before you aquired the kit.
Look for the charging cycle count of each battery. The symptoms you are describing sounds like the batteries are nearing the end of their "useful and safe" life.
15 minutes does not leave you with any headroom, if you fall into a situation that needs more flight time (as in unexpected winds on the way home), needing/looking for a safe spot to land on etc....

 

[Kilrah]

An MP and its batteries can be more than 4 years old by now, if they are it wouldn't be surprising if they are a little worn out and don't have as much flight time as the already optimistic specs.

Would not recommend 3rd party props either.

 

[Cookaboorra]

@Cookaboorra the problem you are encountering has two sources,one is the batteries themselves and the other is the CF props you are using,both these factors will reduce your airtime,and finally you are not helping your cause by running your batteries down to such low voltages as the battery goes below 25% then the cells struggle to deliver enough current ,this causes them to get even hotter and stresses the cells even more ,you will never achieve the stated flight times in real world situations due to the many outside factors that are present when you fly

It's OK, then. Thank you so much. I was not aware of these conditions. Yes, batteries run rather hot after flight time. I was intentionally using them to the bone, to eventually succeed in a better recharge.... my fault.

 

[Flycaster]

Running them "down to the bone" is one of the first ways to kill a lipo battery.

 

[Cookaboorra]

Well, after some evening thought, ( helped by a strong herbal winter liquor ) I decided to purchase a new DJI battery. In fact, as someone here pointed out, I don't really know how many recharges the original ones have beared. Plus, one of them started blinking the third led after the recharge.. surely a bad new.
And yes, I will run with original propellers on.
Nice to be here, boys !

 

[Gygax]

Well, after some evening thought, ( helped by a strong herbal winter liquor ) I decided to purchase a new DJI battery. In fact, as someone here pointed out, I don't really know how many recharges the original ones have beared. Plus, one of them started blinking the third led after the recharge.. surely a bad new.
And yes, I will run with original propellers on.
Nice to be here, boys !

You can check the number of previous battery charges via the battery tab on the flight screen of the DJIGO app. Also of use is enabling the onscreen voltage level as you fly.

FWIW I am an old FPV quad and plane pilot and no stranger to Lipo batteries.. I only ever run Lipos down to 3.8v per cell (storage charge), never leave them sitting at full charge for long, and reliably land my Mavic at between 20 and 30 percent battery level (batt warning set at 30% and critical set at 10%)

Respect your batteries. You cant fly without them ?

 

[Cookaboorra]

Hello !

So the new battery arrived. Tested. The cells give all the same voltage ( not as the previous one ).
I can say that with the same setup it lasts 20 minutes, flying at HIGH quotes. ( I live near Mont Blanc )
So I am happy, now !
JUST an unavoidable more question.....
Three times the drone entered in RTH mode and I was around 55% - 60% charge indicated.
I reported that when climbing up, sometimes cell voltage has reached 3,6 volts, that being the RTH trigger.
The fact is that drone doesn't leave me get out that command, and I have to drive it until it has landed, EVEN if I stop climbing, leave the drone hover, and even if consequently battery gains 0,1 or 0,2 volts, indicating 3,7 or 3,8...
I land safely with almost 25% - 20 % charge available all the times.
Is there any setting I can modify, so to avoid that problem ?

GREETINGS

 

[MAvic_South_Oz]

To be honest I feel a pilot is best not to let the drone do RTH, as it can return way earlier than necessary, and it can also lead to loss of a drone in those dreaded high winds at altitude and / or flying home into a wind.
Plan to return home with about 15-20 % battery remaining as a safety margin, and to keep your batteries in good condition.
Keep charged batteries to around 50% and charge night before flying.
Yours will (should be set to) auto discharge to about 50% after a set # of days anyway.
Always plan flights to the best of your ability, obstacles, wind, etc, it only comes with experience at the controls, and a few close calls where hopefully you can get the bird home safely as part of the learning curve.

 

[Cookaboorra]

To be honest I feel a pilot is best not to let the drone do RTH, as it can return way earlier than necessary, and it can also lead to loss of a drone in those dreaded high winds at altitude and / or flying home into a wind.
Plan to return home with about 15-20 % battery remaining as a safety margin, and to keep your batteries in good condition.
Keep charged batteries to around 50% and charge night before flying.
Yours will (should be set to) auto discharge to about 50% after a set # of days anyway.
Always plan flights to the best of your ability, obstacles, wind, etc, it only comes with experience at the controls, and a few close calls where hopefully you can get the bird home safely as part of the learning curve.

THANK YOU MAN ! It is rally what I have tested in the last few days. I applied the NO RTH mod which excludes low battery voltage RTH, and managed to operate the drone freely until 20 % comes.
I was really a bit scared to do that, due to inexperience. BUT it seems right to have that kind of freedom, if well managed.