Dual Battery Mod

fastfed · Jul 22, 2016

noob question for you guys,

If I wanted to do a battery mod without opening the top, using a battery and adding two batteries to the side of the drone soldering into the main battery, I assume it works all together, all 3 batteries will be drawing equally? Does it show the proper percentage on the app?
and the most important question, how much more time do you get? if I get about 20 min. now, theoretically how much more would I get, being that its much heavier now.

Thanks

Digdat0 · Jul 22, 2016

That's about my level of soldering, but it works fine. I'm a poet, lover and flier ... Not an electrictian

dirtybum said:
Only one hater told that!! I seen it and I thought it looked just fine for the application/purpose[emoji41]

Was on par wit my soldering skills .. Works fine for me!

it aint gotta be purdy, just functional

Digdat0 · Jul 22, 2016

and, today is my day to install 2 new motors .. here's hoping it gets rid of the ESC error which popped up. if not, i have a new bird coming in the mail monday .. not being able to fly is frickin killing me!

dirtybum · Jul 22, 2016

Digdat0 said:
and, today is my day to install 2 new motors .. here's hoping it gets rid of the ESC error which popped up. if not, i have a new bird coming in the mail monday .. not being able to fly is frickin killing me!

You might be out of luck on that one dig! I thought the ESC errors usually involved changing the main board.

dirtybum · Jul 22, 2016

fastfed said:
noob question for you guys,

If I wanted to do a battery mod without opening the top, using a battery and adding two batteries to the side of the drone soldering into the main battery, I assume it works all together, all 3 batteries will be drawing equally? Does it show the proper percentage on the app?
and the most important question, how much more time do you get? if I get about 20 min. now, theoretically how much more would I get, being that its much heavier now.

Thanks

Yeah man just mod the battery if you'd like, a light pair of Maxamps 2000's Will get you 30 minutes

Digdat0 · Jul 22, 2016

dirtybum said:
You might be out of luck on that one dig! I thought the ESC errors usually involved changing the main board.

i hope not

I had a motor seize after a flip at the beach.. esc error came on a few times after, but not always. I think its cause the motor itself is is bad, it does not spin freely and heats up 100x faster than the others (I'm thinking some sand). . I was gonna replace the motor anyways, just hoping it also resolves the esc. If so, $17 was better than $150. If not, I already bought another p3p as my proper replacement, so this is really a chance to learn and try it out. I'll have backup parts, and i can get a new mainboard if needed and will have 2 phantoms. I'm not sure i can have enough, i'm accident prone.

Digdat0 · Jul 22, 2016

fastfed said:
If I wanted to do a battery mod without opening the top, using a battery and adding two batteries to the side of the drone soldering into the main battery, I assume it works all together, all 3 batteries will be drawing equally? Does it show the proper percentage on the app?
and the most important question, how much more time do you get? if I get about 20 min. now, theoretically how much more would I get, being that its much heavier now.

Yes, you can do a battery mod without opening the top. You need to modify the stock battery, or buy a modified one. They look like this (this is the inside wiring):

You then add external batteries on from there. The additional batteries plus the stock will all add up and give power. The app will not show the proper % remaining for a bit. Usually adding more batteries takes you over a 25min flight time - the DJI go app can only show 25mins or less. So it will look like --/-- in the app, showing no time until the battery power decreases to less than 25min time total. And, the % will not always reflect proper value at first either, so I use volts rather than %.

I bought the Horizon v3 5200 power mod, my best time was 29m30seconds. Other than that, all my flights are at ~26m down to 10% battery. I bought a pair of Venon Fly LiHV 2300's and, running off one single, i got a 26 min flight. I get 16-18min on my stock batteries.

Ed209 · Jul 22, 2016

dirtybum said:
Only one hater told that!! I seen it and I thought it looked just fine for the application/purpose[emoji41]

Yeah I was being sarcastic. I'm not good like a robot dropping perfect blobs but I know how to ensure a strong, conductive bond and never have had a solder weld fail ever. I've soldered since college time 15+ yrs ago so I'm pretty confident in my abilities. Heck even my own split mods during the winter held up and performed just as shitty as the ones we tested back then [emoji24]

Digdat0 · Jul 22, 2016

got one new motor installed, re-calibrated IMU and ESC error is gone

I did the power mod to the aircraft, ran two power leads. my soldering sucks .. but it works grrreeeatttt!

and my new motor.

Now for a test flight!

Digdat0 · Jul 22, 2016

oh yeah, be careful with your soldering iron boys, **** happens easily and quickly.

Ed209 · Jul 22, 2016

Digdat0 said:
oh yeah, be careful with your soldering iron boys, **** happens easily and quickly.

Nice. Now queue the soldering critics [emoji3]

Digdat0 · Jul 22, 2016

okay here's the final product with the Venom Fly 2300s. last set of pictures

I really appreciate all of the knowledge and information sharing from everyone on this forum.

I also found that with the direct power mod, the externals can end up charging the battery as Silverwingflinx noted earlier. But, If i get my batteries to 100%, that doesn't happen. Otherwise, I have to take down the juice on the externals just a bit. Its not as often as the battery mod though.

dirtybum · Jul 23, 2016

If you can plug the externals in and get your remote and start those engines up in 10 to 15 seconds you'll have a lot better luck

dirtybum · Jul 23, 2016

Digdat0 said:
oh yeah, be careful with your soldering iron boys, **** happens easily and quickly.

Ed209 said:
Nice. Now queue the soldering critics [emoji3]

**** Dig, is your soldering iron the size of a hotdog? Ha ha, I'm glad it was just the motor not the main board.

shockwave199 · Jul 23, 2016

What indicates the battery is charging by mistake? Does it blink the green leds in sequence even if the battery is 98% or 100% charged? Under normal circumstances it is very often my battery will actually show 98%, not 100%. But I don't remember if the leds are solid green regardless. I've only flown with my battery mod once and it was fine. I took DB's advice at the time and plugged the 5200's in and started the bird up right away. I can do that easily because I'm wearing my remote. I'll keep to that routine for sure and maybe charge the externals a bit less than full.

Alex Baxter · Jul 23, 2016

Jeez, what's the RTF weight, the motors must be screaming like a startled teenager?

Digdat0 · Jul 23, 2016

shockwave199 said:
What indicates the battery is charging by mistake? Does it blink the green leds in sequence even if the battery is 98% or 100% charged? Under normal circumstances it is very often my battery will actually show 98%, not 100%. But I don't remember if the leds are solid green regardless. I've only flown with my battery mod once and it was fine. I took DB's advice at the time and plugged the 5200's in and started the bird up right away. I can do that easily because I'm wearing my remote. I'll keep to that routine for sure and maybe charge the externals a bit less than full.

For me, it's one of two things. Either, the lights flash like they are charging, or they start charging and then turn off .. All lights go out and the stock battery powers off. In both cases, the externals still power the aircraft, but in the second case the stock battery turned off and Dji go shows battery connection error. I can still fly, but no percentage reading or volts from battery.

Mikepoo · Jul 23, 2016

Digdat0 said:
got one new motor installed, re-calibrated IMU and ESC error is gone I did the power mod to the aircraft, ran two power leads. my soldering sucks .. but it works grrreeeatttt!

and my new motor.

Now for a test flight!

Your soldering is better than mine.

shockwave199 · Jul 23, 2016

Digdat0 said:
For me, it's one of two things. Either, the lights flash like they are charging, or they start charging and then turn off .. All lights go out and the stock battery powers off. In both cases, the externals still power the aircraft, but in the second case the stock battery turned off and Dji go shows battery connection error. I can still fly, but no percentage reading or volts from battery.

I see, thanks. I can deal with a little annoyance preflight but in the air that's catastrophic. I'm really glad that hasn't been reported.

Digdat0 · Jul 23, 2016

shockwave199 said:
I see, thanks. I can deal with a little annoyance preflight but in the air that's catastrophic. I'm really glad that hasn't been reported.

On two occasions i did have the charging issue happen in air (i plugged in fast and took off quickly), and the main battery powered off (I think cause it thought it was fully charged). in both cases the externals still powered the aircraft and i could control it just fine. I received a battery signal error, but video and RC control maintains and I was able to bring it back. I was only a few feet away, but was a little scary.