Mavic Pro Battery Mod

dirtybum · Dec 7, 2017

Thunderpowers suck!

lolo780 · Dec 7, 2017

mubytrid said:
Thunderpowers suck!

Hopefully a Multistar vs Thunderpower vs Protek comparison can be done soon. I went 125,100ft yesterday on a tp3500+4500 setup so can't be that bad.

I thought I'd try battery modding straight to the mosfets, but it throws the current readings off so there's no wattage data from my run.

CyberNate · Dec 7, 2017

mubytrid said:
Thunderpowers suck!

I wouldn't say that. They are more similar to the Mavic internal cells in behavior according to Lolo's results. You just don't get that huge first 10%, but a more linear output. We will see.

dirtybum · Dec 7, 2017

lolo780 said:
Hopefully a Multistar vs Thunderpower vs Protek comparison can be done soon. I went 125,100ft yesterday on a tp3500+4500 setup so can't be that bad.

I thought I'd try battery modding straight to the mosfets, but it throws the current readings off so there's no wattage data from my run.

Post the air data for that one, not that technical spreadsheet, thanks

chazz · Dec 7, 2017

AMain Hobby's having a pretty good deal today i bought a couple of those Protek 3600's - $20 bucks off.

12 Days of Deals: Save $20 On Orders of $100 or More

CyberNate · Dec 7, 2017

Packs are light! Around 219 grams! Usually batteries weigh more than advertised. Much smaller than Multistar 4000! Will work nicely side mounted

lolo780 · Dec 7, 2017

mubytrid said:
Post the air data for that one, not that technical spreadsheet, thanks

Not sure why but the Go app won't save the .txt file on longer distance flights. The device side data is mostly useless anyways. No pitch, roll, motor power, currents etc.

dirtybum · Dec 8, 2017

lolo780 said:
Not sure why but the Go app won't save the .txt file on longer distance flights. The device side data is mostly useless anyways. No pitch, roll, motor power, currents etc.

So when you do a record distant run you won't be able to offer an airdata link?

lolo780 · Dec 8, 2017

mubytrid said:
So when you do a record distant run you won't be able to offer an airdata link?

Screen recording of the entire flight and .dat file. I just changed to the latest hacked and patched Go app 1.14 so will see what happens next flight. The longest flight it saved was 28.xx km. Anything else doesn't save.

Phxbird57 · Dec 8, 2017

second flight video of the duel Protek 3600 batteries. airdata is projecting 45 minute. We will see if that comes true. Temps have finally drop here too. Cyber with 3 batteries you should be looking in the 50ish minutes
https://youtu.be/TF5iKhqngf

CyberNate · Dec 8, 2017

Phxbird57 said:
second flight video of the duel Protek 3600 batteries. airdata is projecting 45 minute. We will see if that comes true. Temps have finally drop here too. Cyber with 3 batteries you should be looking in the 50ish minutes
https://youtu.be/TF5iKhqngf

Not running 3 yet. That is only for aggressive weight cutting. Starting out like you, some easy flights, but I think I'll try platinum propellers.

CyberNate · Dec 8, 2017

Did a test flight today with Protek and Platinum Propellers. I'm not seeing as good of results, but it might be props or the battery mod on this bird. I tried to solder to the board, but I ended up soldering on top of the solder points rather than getting it really down to the board. I'm seeing some voltage lag which is evident when I land and the voltage jumps up quite a bit. I'll check my external voltages later. I was seeing 3.80V just before landing in the app, so we'll see what the externals register. May have to redo my battery mod.

I'll try another run soon with the standard props. These Platinum do well with stock mavic, but with extra weight there's a point where they are less efficient.

Airdata UAV - Flight Data Analysis for Drones

Youtube of screen recording, still being processed at the moment:

dirtybum · Dec 8, 2017

One battery or two.
If only one you can't be mad at that, a 40 minute prediction in airdata

CyberNate · Dec 8, 2017

mubytrid said:
One battery or two.
If only one you can't be mad at that, a 40 minute prediction in airdata

That's 2 batteries.

lolo780 · Dec 8, 2017

Watt second half way point (398,000 total to the motors) from my almost record flight, short by 68ft off Unknowncaller's #1. A lot of time spent over 200W on the way out fighting headwinds and climbing over 200m to keep HD signal. 230W near the turnaround point and you can see the battery % dropping steeply. 135W on the way home cruising at 15.8m/s.

Battery setup is Thunderpower HV, 3500 + 4500. Pre flight charge 3952 and 4906mAh. Post flight charge was 3553 and 4583mAh and DJI battery was showing 200mAh remaining on landing. DJI battery shows 3782mAh capacity, so a little bit down from new. Remaining capacity could probably squeeze another 2500m or so if needed.

chazz · Dec 8, 2017

Hey lolo have you ever looked at that chart to see what is happening when it hits autoland around 3.5V? Maybe once you can do it without pushing the elevation stick up and not fight it and let it land from around 50' and maybe we can see whats going on or what triggers it. Maybe showing the volts,current and watts...I think if you push the stick up it will hide whats going on because it's compensating for whatever is happening.

dirtybum · Dec 8, 2017

lolo780 said:
Watt second half way point (398,000 total to the motors) from my almost record flight, short by 68ft off Unknowncaller's #1. A lot of time spent over 200W on the way out fighting headwinds and climbing over 200m to keep HD signal. 230W near the turnaround point and you can see the battery % dropping steeply. 135W on the way home cruising at 15.8m/s.

Battery setup is Thunderpower HV, 3500 + 4500. Pre flight charge 3952 and 4906mAh. Post flight charge was 3553 and 4583mAh and DJI battery was showing 200mAh remaining on landing. DJI battery shows 3782mAh capacity, so a little bit down from new. Remaining capacity could probably squeeze another 2500m or so if needed.

How do you tell how much MAH is in your externals before you fly after you charge them. My charger only shows how much I put into them during charging

dirtybum · Dec 8, 2017

CyberNate said:
That's 2 batteries.

Yeah that's not great then huh

lolo780 · Dec 8, 2017

chazz said:
Hey lolo have you ever looked at that chart to see what is happening when it hits autoland around 3.5V? Maybe once you can do it without pushing the elevation stick up and not fight it and let it land from around 50' and maybe we can see whats going on or what triggers it. Maybe showing the volts,current and watts...I think if you push the stick up it will hide whats going on because it's compensating for whatever is happening.

I have the voltage settings at minimum, but can't remember what it is. I routinely fly down to 3.4v under load before worrying about landing. What were you wondering? I can check some old logs.

lolo780 · Dec 8, 2017

mubytrid said:
How do you tell how much MAH is in your externals before you fly after you charge them. My charger only shows how much I put into them during charging

39xx and 49xx are from the charge cycle prior to flying. The TP batteries seem to have more capacity than advertised, or my charger is optimistic.
Cybernate should be able to prove or disprove this.