Awesome dude, thanks for the advice! Ill bring batteries, bearings and some .2 nickel.
6 Likes
Getting moving on my 12S2P pack.
First few welds going on.
0.15 x 30 mm nickel.
Malectrics with 2 lipos.
20ms on the negative side and 21 or 22 on the positive side.
I usually keep the positive probe in place and hit the negative in 3 spots.
3 Likes
Yep thank you this worked perfectly
2 Likes
Not sure if this was a good idea. What do You mean guys? Can I leave it? Ír was made by KWeld 50j( 2x turnigy rapid lipos) 0,2nickel . Thanx a Lot For Your support
That looks a bit dangerous. You spot welded on the area where its just an empty gap, try to do it right in the middle of the cell if on the positive side, and around the cell on the negative
Also, thats quite a lot of spots per cell. I usually do 6 in a hexagonal shape
5 Likes
Take some of your ring gaskets and lay them on top of the nickel trying to match the ones below to try and get a better idea of exactly where those welds are. If they are on the very edge of the can, which is actually the negative part of the can, this could be very dangerous. It could end up needing nothing more than vibration to fail catastrophically.
Your joules are too high. Some of your welds are just about to blow through the nickel. You can tell by how much nickel they are displacing, leaving what looks like a crater. The brown rings is another indicator that you are running on the hot side. I can design and print welding placement jigs for anyone who needs them in any configuration.
2 Likes
Thanx. I will make and print fixtures for next time. I was using less J just was little confused for the values which are people using. Iam already analise it and i have one mm clearence from each side in worst case. And the welding point closer to cells is on bouble layer of sheet so assume that opposit side looks better. I can remove it and foot again but not sure what is better solution.
1 Like
I’m not sure what the best solution is, either. I wonder if filling the holes with something is an option. Just to stabilize the nickel. Perhaps you could figure out a way to lift it first. Expanding foam comes to mind but I don’t know if it’s electronics safe. Just thinking out loud.
1 Like
Good point. It is already partialy filled by silicon. I will try to move surface up from opposit side. Will see what will be the result. If it will be ok, I will complet fill it by neutral silicon. Thanx
1 Like
You’re welcome.
1 Like
Hey guys.
Question about series connections.
P42A packs 12S2P and 12slS3P
I was leaning on doing 2 x 14 awg wires for my series connections.
But can I just get by with 1 x 12 awg wire?
It would be nice to reduce those steps provided I’m not sacrificing integrity.
But maybe it’s ok since these are smaller P groups.
What would be the best way to go?
Depends on your max amps goals imho. Two 14awg wires have 50%ish more capacity than one 12awg. There is also the redundancy of two 14awg if you aren’t confident in your solder joints.
If one 12awg will get you what you’re looking for then go for it.
1 Like
I want connect doublesheet. Now it is complet removed and reworking it. But when I opened it , it was not so bad. It was realy in free space.
1 Like
@rafaelinmissouri in addition to redundancy, multiple, smaller wires also reduces resistance which is also highly beneficial. Ultimately, it all depends on what you terminate your main output with. If you are using 12 awg then running the same wires as series connections will work just fine if not as optimally as 2 x 14 awg.
3 Likes
Thanks guys.
I am not expecting to pull anything crazy from these packs.
Probably 30 amps on the 12S2P
And 46 on the 12S3P
The main termination is 12awg on an XT60.
I am now leaning towards just doing the 1 x 12awg for the series.
It seems it should be adequate.
4 Likes
Sorry if this is a dumb question, but is this wired correctly if I want to bypass BMS discharge? Having a hard time interpreting the diagrams that I’m finding.
(Ignore the overlapping wires)
Is it necessary to have both B- connections going to the battery negative or is that a redundancy?
1 Like
Only need one of each
2 Likes
both the B Negative terminations on the bms are connected on the pcb so really your drawing only needs one C+ and one C- and your wiring only needs one wire from the bms to the batt (LLT bms?)
1 Like
Also, you do not show the ESC here. The ESC would be connected directly to the battery, assume you knew that already though.
2 Likes
this is a decent video if you find that helpful:
3 Likes