Mavic Pro Battery Mod

TheLightSpeed! · Aug 8, 2017

beanbubba said:
Hey veterans... on this last crash and several other flights I have noticed the front rotors are always hotter than the rear after a flight. On this last flight I purposely moved the center of gravity farther towards the rear to hopefully account for this phenomenon. After the crash, I couldn't even touch the front rotors and they must have been approaching flash point. Yet I could hold the rear motors without getting burnt. And this was a brand new Mavic that hadn't been frankenmavic'd yet and should be a good representative of performance results.

Does anyone have any data points or experiences on this topic you could share?

Dude that's a warranty claim if I ever seen one! "DJI my motor just melted off? What's the hell? Also it hit my Ferrari on the way down and ruined it!!! I demand repayment!"

digdat0 · Aug 9, 2017

100 pages!

dont wanna brag, but i got a 21m50s stock battery flight tonight in 85+ degree weather. The last 4 mins were hover above my house, but .. thats one of my longer stock battery flights.

dirtybum · Aug 9, 2017

digdat0 said:
100 pages!

dont wanna brag, but i got a 21m50s stock battery flight tonight in 85+ degree weather. The last 4 mins were hover above my house, but .. thats one of my longer stock battery flights.

brag all you want, Ed209 got 1300 mins stock battery, let me guess your max altitude was 20 feet[emoji41]

dirtybum · Aug 9, 2017

beanbubba said:
Hey veterans... on this last crash and several other flights I have noticed the front rotors are always hotter than the rear after a flight. On this last flight I purposely moved the center of gravity farther towards the rear to hopefully account for this phenomenon. After the crash, I couldn't even touch the front rotors and they must have been approaching flash point. Yet I could hold the rear motors without getting burnt. And this was a brand new Mavic that hadn't been frankenmavic'd yet and should be a good representative of performance results.

Does anyone have any data points or experiences on this topic you could share?

that's interesting a certain Mavic expert on this forum that goes by the name of Nate claims that the rear motors take all the heat and that you should move everything forward to compensate. You guys should work it out in a battle rap[emoji41]

beanbubba · Aug 9, 2017

dirtybum said:
that's interesting a certain Mavic expert on this forum that goes by the name of Nate claims that the rear motors take all the heat and that you should move everything forward to compensate. You guys should work it out in a battle rap[emoji41]

FWIW - this crash was a hover test which I am sure probably produces different results??

TheLightSpeed! · Aug 9, 2017

BeanBubba burns through Mavics like I change socks.

beanbubba · Aug 9, 2017

TheLightSpeed! said:
BeanBubba burns through Mavics like I change socks.

That is the start of a great rap riff...

singlag · Aug 9, 2017

Some Battery/flight time date to share

According to this data, we can calculate the other battery

singlag · Aug 9, 2017

2 New test, DIY clip with solder to pin, seem no different

Mavic Pro with multistar 4000mah 10c Lipo with diy clip with solder
Landing : @29%
flight time: 25min 52second (2km+ range test)
Estimate-Max Flight Time : 36min
Mah/Sec : 3.499
Idle RPM : 6800rpm
Airdata UAV - Flight Data Analysis for Drones

Mavic Pro with Zippy compact 2200mah Lipo with diy clip with solder
Landing : @48%
flight time: 19min 49second (Strong wind)
Estimate-Max Flight Time : 31min
Mah/Sec : 3.14
Idle RPM : 6500rpm
Airdata UAV - Flight Data Analysis for Drones

sprtbkrydr · Aug 9, 2017

dirtybum said:
that's interesting a certain Mavic expert on this forum that goes by the name of Nate

Come on now let's leave the name bashing out of the picture here. No sense in all that.

singlag · Aug 9, 2017

I found that, the external li-po battery will have high voltage than DJI battery after landing, such as landing @15%, DJI battery is about 3.6+ V but external li-po battery have 3.7+ V, is it normal ?

DJI battery will cutoff @3.5v (0%) and external li-po still have 3.6v+
so, what voltage is safe cutoff voltage for Li-HV (dji)?

cptlores · Aug 9, 2017

beanbubba said:
I was thinking the same thing!! Does anyone know the outer temperature limits of the mavic motors (or similar motor) before they fail?

At around 80C (175F) the magnets start to demagnetize. And at around 180C (360F) the solder starts to melt. So around 80C you start to degrade motor performance, and anything over that is just a question of what goes first. Total demagnetizing or melting wires insulation / solder points.

sprtbkrydr · Aug 9, 2017

singlag said:
I found that, the external li-po battery will have high voltage than DJI battery after landing, such as landing @15%, DJI battery is about 3.6+ V but external li-po battery have 3.7+ V, is it normal ?

DJI battery will cutoff @3.5v (0%) and external li-po still have 3.6v+
so, what voltage is safe cutoff voltage for Li-HV (dji)?

You have asked this same question many times but the answer is yes, this is what everyone else see's as well.

singlag · Aug 9, 2017

sprtbkrydr said:
You have asked this same question many times but the answer is yes, this is what everyone else see's as well.

how many times you have count ?
and what is your suggested answer ? 3.4v ?

sprtbkrydr · Aug 9, 2017

singlag said:
how many times you have count ?
and what is your suggested answer ? 3.4v ?

my answer would be 3.4volts

sprtbkrydr · Aug 9, 2017

singlag said:
how many times you have count ?
and what is your suggested answer ? 3.4v ?

And that made 13 times!!

Ed209 · Aug 9, 2017

Alright so this has me thinking... if the battery cuts off at 3.5v... If someone were to change that, what is the lowest voltage the electronics inside will stay powered on? Do the components themselves have an internal cutoff?