Mavic Pro Battery Mod

[TheLightSpeed!]

I did a hover test with the battery board turned off yesterday and at about 20 min into the flight the dreaded critical low voltage landing at a little under 3.5V...I had high hopes for this one...

Chazz, the only thing I can think of is the battery settings in the Assistant 2.

I have mine on Non DJI Battery, and to flash only for the critical battery functions.

 

[TheLightSpeed!]

I did a hover test with the battery board turned off yesterday and at about 20 min into the flight the dreaded critical low voltage landing at a little under 3.5V...I had high hopes for this one...

For what it is worth I was using a 5.2 mah Multistar on a battery with over 30 cycles. It would charge the battery right away.

 

[Ed209]

Hey man don't forget if you plug the battery into the board before you plug it into the mav there is power goin to those pins...I made sparks a few times when i didn't line it up correctly..

Thanks for the heads-up. The balance leads are coming Sat according to USPS. We'll see.

 

[digdat0]

I got a pair of bolt 2400 lihv 3s im gonna test today. First charge and a 3 min hover under the covering showed 30mins. Im hopeful for a flight today even if just flying around. Also picked up a pair of zippy lipos 2200 just for the heck of it.

 

[Ed209]

View attachment 22054 View attachment 22055 View attachment 22056 I got a pair of bolt 2400 lihv 3s im gonna test today. First charge and a 3 min hover under the covering showed 30mins. Im hopeful for a flight today even if just flying around. Also picked up a pair of zippy lipos 2200 just for the heck of it.

I'm interested to see the performance and discharge you get with those bolts... Another high C rating test. Will be interesting!

 

[digdat0]

not great results, but the first charge/first run for both sets of batteries. was really, really expecting more from the bolts. the zippy 2200's did better.

bolt 2400 lihv: Airdata UAV - Flight Data Analysis for Drones
zippy 2200 lihv: Airdata UAV - Flight Data Analysis for Drones

bolt: 24m 15s, 70,396 ft total, landed 1/0%
zippy: 25m 25s, 69,904 ft total, landed 2% (low volt landing tried to kick in at 15% then went away, will post screen rec later)

i had non-dji bat set to avoid autolanding, also had my gps speed at 36/37 mph, so that could be why less time. i'll put back to stock and try again.

 

[Ed209]

not great results, but the first charge/first run for both sets of batteries. was really, really expecting more from the bolts. the zippy 2200's did better.

bolt 2400 lihv: Airdata UAV - Flight Data Analysis for Drones
zippy 2200 lihv: Airdata UAV - Flight Data Analysis for Drones

bolt: 24m 15s, 70,396 ft total, landed 1/0%
zippy: 25m 25s, 69,904 ft total, landed 2% (low volt landing tried to kick in at 15% then went away, will post screen rec later)

i had non-dji bat set to avoid autolanding, also had my gps speed at 36/37 mph, so that could be why less time. i'll put back to stock and try again.

Def doing 36/37 knocked power down a bit. Especially when your were flying into the wind. I had a flight with 2x 1700mAh (not LiHV):

20:56 ~ 31%
Airdata UAV - Flight Data Analysis for Drones

That was a leisurely 5.2mi distance run to test the packs. Airdata estimated 30:31 run time. I think you should try again with normal GPS speeds. I doubt it will be a tremendous difference though.

 

[CyberNate]

not great results, but the first charge/first run for both sets of batteries. was really, really expecting more from the bolts. the zippy 2200's did better.

bolt 2400 lihv: Airdata UAV - Flight Data Analysis for Drones
zippy 2200 lihv: Airdata UAV - Flight Data Analysis for Drones

bolt: 24m 15s, 70,396 ft total, landed 1/0%
zippy: 25m 25s, 69,904 ft total, landed 2% (low volt landing tried to kick in at 15% then went away, will post screen rec later)

i had non-dji bat set to avoid autolanding, also had my gps speed at 36/37 mph, so that could be why less time. i'll put back to stock and try again.

Those bolt batteries are just too heavy for a 2400mah battery. I also think 36-37 mph is too fast. I have tried the higher speeds a couple times and I do see diminished battery life so far. Myself and Keith have had our best runs at 32mph out (stock P-mode with obstacle avoidance off) on the way out, and RTH mode with full right still all the way home which gives 33.6mph. That is with the heavy Multistar dual 4000 LiHV.

 

[digdat0]

thanks ed. just reset back, recharging. will see if we can get another in today, its nice. rain started, which is a double edged sword.

 

[chazz]

not great results, but the first charge/first run for both sets of batteries. was really, really expecting more from the bolts. the zippy 2200's did better.

bolt 2400 lihv: Airdata UAV - Flight Data Analysis for Drones
zippy 2200 lihv: Airdata UAV - Flight Data Analysis for Drones

bolt: 24m 15s, 70,396 ft total, landed 1/0%
zippy: 25m 25s, 69,904 ft total, landed 2% (low volt landing tried to kick in at 15% then went away, will post screen rec later)

i had non-dji bat set to avoid autolanding, also had my gps speed at 36/37 mph, so that could be why less time. i'll put back to stock and try again.

Hey Dig can you do me a favor and look at the voltage when autoland kicks in? I think there are two things that cause it either the 10%-15% mah remaining or the 3.5V critical..I think having the battery set to the nonDJI battery thing stops the 10%-15% but not the 3.5V one...Mine hits 3.5V and it seems it loses power and nothing i can do but push the stick up...

 

[lolo780]

Have you changed your battery warning voltage levels in Assistant?

 

[chazz]

Have you changed your battery warning voltage levels in Assistant?

Changed all that i know of. Which ones would you suggest?

 

[digdat0]

Hey Dig can you do me a favor and look at the voltage when autoland kicks in? I think there are two things that cause it either the 10%-15% mah remaining or the 3.5V critical..I think having the battery set to the nonDJI battery thing stops the 10%-15% but not the 3.5V one...Mine hits 3.5V and it seems it loses power and nothing i can do but push the stick up...

yeah i got the logs copied over my son stole my laptop and is playing minecraft. Will post up some volt charts later but heres screen cap from go when it came up

 

[chazz]

yeah i got the logs copied over my son stole my laptop and is playing minecraft. Will post up some volt charts later but heres screen cap from go when it came up

Thanks! Is it typical to have 3.33V at 17% its been so long since i flew with a regular battery i forgot..3.33V seems pretty low to me at 17%....When my critically low comes up it say it in the spot where it says "ready to fly GPS" and scrolls across there in red....

 

[digdat0]

Thanks! Is it typical to have 3.33V at 17% its been so long since i flew with a regular battery i forgot..3.33V seems pretty low to me at 17%....When my critically low comes up it say it in the spot where it says "ready to fly GPS" and scrolls across there in red....

Yeah that seemed really low at 17% .. the kther flight i had 3.5v at 17%,didnt go that low until 2%

 

[lolo780]

I'll have to check my battery settings tonight, but I set them and haven't changed them since. Flew another 270sec after the counter hit 0%, but even at 0%, the DJI battery continued to count down voltage.

 

[chazz]

I wonder what was different...Seems its more then voltage or Mah that makes the critical thing come up. I modified my battery board and i sorta understand why my % doesn't go down as quick as it should so with my flight Mah % had no influence on the critical landing...only the 3.5V or maybe it isnt the that causing it and just a coincidence i really don't know...Because on your flight its at 3.3V and just came up...


Airdata UAV - Flight Data Analysis for Drones

 

[Ed209]

Could be the battery sagging at the end of its charge. Also total aircraft weight and wind and flying style?

 

[SkyNinja]

Could you post up the voltage discharge curve for that flight?

I couldn't open the file on my Mac. If you're still interested in the discharge curve for that flight here's a link to it.
FLY214.DAT

 

[chazz]

Could be,,, i do notice a lot of voltage drop with this battery but i really don't remember whats normal and the airdata isn't really showing any red flags...The lion batteries i got do have a low C rating if that has anything to do with it..This thing's taking lot of measurements and doing a lot of calculations i guess it could be anything...