Changing battery connector on drone

Hi all,

When changing the battery connector on the drone, is it better to change the entire lead (remove original cable from FC), or just remove the actual connector from the cable and attach the new one?

On that note, anything in particular, aside from the +/-, one should be cautious of?


It really depends on what you are more comfortable with.

Replacing the whole lead means you may need to resolder the smoothing capacitor on the ESC/powerboard too.

In terms of what else to watch for, if you do replace the whole cable, make sure the new cable is clear of the props, make sure the length and routing is as close to original as possible (or even better in terms of routing than the original may have been).

This is not quite the same question but similar and related so thought not worth own thread, but I see capacitors on the xt30/60 and at the FC end. All mine are FC end, but one one of mine it’d be better for space purposes at the xt30 end. Is that ok? Want to put longer cable on anyways. Also what’s recommended capacitor for a 3s?

The effectiveness is reduced the further they are from the ESC. So it’ll work, just not as well.

1 Like

I’d do this… I hate soldering to the ESC… it’s always a tough place to solder.

I couldn’t put numbers on it, but as long as the wire is thick enough or short enough (low enough resistance) it’s no problem having the capacitors at the XT plug end.

For 3S, I’d say that a 35V or 50V 470uF should do, but you’d probably want to get a second opinion on that.

3S fully charged is 12.6v (4.2x3), double it = 25.2v so go up to 35v
4S fully charged is 16.6v (4.2x4), double it = 33.4v so go up to 50v
For capacitor to work at it’s full value, within tolerance, you need AT LEAST twice the supply voltage
This has been covered before but God knows were that post is :smile:

1 Like

Of course there a Bardwell video on where… With science too lol

Every day a school day lol

1 Like

Thx for the answers guys!

I’ll try just removing the connector first, seems less riskier to me. I’m going to repurpose a connector that already has cables on. Any issues on soldering cable to cable (ie nip the cable close to the connector and solder both pairs together)? Or is it more advisable to remove cables from existing connectors and then solder FC leads directly on the new connector?

Sorry for the questions, its my first time doing this and I don’t want to mess it up…


Don’t have a join in the wires
Unsolder your repurposed connector, unsolder your existing connector, solder repurposed to the wires on the quad
Clean off old solder, use fresh solder and add flux if you need to, to keep the joints shiny
Don’t forget to fit new insulation, heatshrink sleeving

Thx dude!

Will be my first drone operation (starting off with the simple stuff and work my way in)… lol

Soldering the pigtail to the FC/ESC is probably the hardest bit of making a quad TBH, I know @yith isn’t a fan either! Due to size and heat. The small RX/TX, etc for cams is easier as they smaller, in and out quick :slight_smile:

Operation has been completed, successfully might I add (at least on initial testing).

I ended up having to do it the harder way though.
The lead on the drone was way too short for batteries with no cables on them so I removed the whole thing and soldered the cables from the other connector. I’m not going to lie, it wasn’t a walk in the park for me. The solder pads are quite small and close to one another, I had to redo them a few times, and although its all working now, with no shorts, it doesn’t look very nice (it didn’t help the fact that I didn’t want to remove the canopy and had to negotiate with a tighter space, just to make things more challenging lol) . Might have to touch up on it in the future after acquiring a bit more practice.

Another thing that was quite evident from the experience is that my eyes are not what they used to be, just added a one of those magnifying glasses lamps to the list of things to buy… lol

The man!

I get by with ÂŁ1 reading glasses from poundland.

1 Like

I did pull out the glasses from the drawer but still wasn’t the best. Might need to recheck the prescription of those since its been a while since I last checked and I rarely use them…

1 Like

The misses keeps telling me to get my eyes checked. But life’s too short. And it will be when I plough into an M11 traffic jam :man_facepalming:

The more you use it the worst it gets, so might as well try not using it until its inevitable…

It shouldn’t make any difference. The primary purpose of the capacitor is to surpress the transient high voltage spike that’s created when the battery is first connected. The capacitor is mounted at the board as its less likely to get ripped off in a crash.

Esc’s, especially those intended for FPV applications, will have suitable LCR filtering built in.

Afraid I must agree with @Yith
Main purpose of this capacitor is to protect other components, especially VTX, when ESC is active braking the motor and enormous transients are chucked onto the main supply lines.
I always put mine as close to the LiPo connection to the ESCs as I can get it, this maybe on a 4in1 ESC board, AIO flight controller or even four smaller capacitors at each ESC if individuals used.

I’m going to even things up by saying that I thought they are basically electrically identical, whichever end of the pigtail you put it at. The only difference is the resistance in the wires, which should be negligible? But I’m not an electronics buff. :wink:

What I will say about soldering wires to connectors is that I now always do it with the partner connector plugged in, because if I don’t I have a tendency to overheat the pins, soften the plastic and end up with wonky pins that then won’t plug in. That’s a real life lesson from a shoddy solderer, so I’m standing by that one. :grin: