"Copper/nickel sandwich" buses for series connections

Back on topic... :)

I found this .3mm copper with nickel coating on each side. I have bought a roll of it to try out. Maybe it will spot weld like a little section of nickel does on top of copper? I've been buying nickel from this guy for a while now and just saw he had this.

https://www.ebay.com/itm/133104900617?var=432415150002
 
Cool!

key issue is, if the plating is thick enough to increase the copper's resistance enough

Please let us know!

Are you using Kweld with caps or lipo or? Optimizing the joules output might be critical
 
ridethelightning said:
ace man! that looks like good stuff. how did you get .3mm,? link is 0.15mm i saw

LOL...typo on my part...said the wrong thickness. Oopsie!

john61ct said:
key issue is, if the plating is thick enough to increase the copper's resistance enough
Please let us know!

Are you using Kweld with caps or lipo or? Optimizing the joules output might be critical
I posted it so that others might give it a try too, but yeah...I'll be posting if I can spot weld it or not.

I have a KWELD and 2 super cap modules in parallel and dual 50 amp PSU's keeping all of that powered up. Super cap voltage and charge level never lags behind my welding speed. I have to stop for hot weld probes, but not for the super caps to catch up. I also made the wires between everything as short as possible to reduce resistive losses to the minimum. For portable use, I built an LTO pack that is about 44Ah. Either way, it all plugs into the dual super cap modules.
 
Great stuff.

Best to also post this setup description with your results if successful to the main KWELD thread for reference there.

Using the kcap units in effect insulates the main unit from batteries that have too high/fast power output, is that correct?
 
id be keen to see if you manage to weld the nickel plated copper.
i tried plating my own but the power of the weld pulse for copper just flashed off the nickel when i tried to weld it.

if i can find some tin it may prove to be better.

i dont know how the power tool packs are done, many use plated copper. i may try welding some of the strips from them onto cells.
 
john61ct said:
Great stuff.

Best to also post this setup description with your results if successful to the main KWELD thread for reference there.

Using the kcap units in effect insulates the main unit from batteries that have too high/fast power output, is that correct?

Uhhh...no idea about the super caps doing that or not.

I got the super cap modules because I wanted to run from a PSU instead of a battery for hours and hours of spot welding. I started with a 20 amp Meawell and that was OK, but my weld speed had to stay sloooow or else I'd run out of charge after a minute. 2 supercap modules got me a bit more weld time, but also doubled how long that PSU took to charge them up again. This got pretty tedious! I then bought a 50 amp Meanwell and that was much better, but I could still weld faster than it could keep up the charge on the super caps. I then bought a second 50A Meanwell to put in parallel with the first one. They do the trick! I never weld fast enough for long enough that they can't keep the super caps charged. Invariably, I need to stop to cut or place another piece of nickel or because the weld pens get hot and the 2 PSU's quickly catch up any deficit that I never notice.

With this setup...100 amps seems like a lot from a 15 amp AC circuit, but it's also stepped down to 9v. This is a bit over the limits for the super caps, but they are not harmed and the fans on them barely ever run. Anyway, 900 watts, 100 amps and 9v is about 7.5 amps at 120v. I've never popped a breaker with my KWELD setup.
 
ridethelightning said:
id be keen to see if you manage to weld the nickel plated copper.
i tried plating my own but the power of the weld pulse for copper just flashed off the nickel when i tried to weld it.

if i can find some tin it may prove to be better.

i dont know how the power tool packs are done, many use plated copper. i may try welding some of the strips from them onto cells.

Probably the thickness of the nickel is the key. I know that spool of nickel plated copper has a really thin layer of nickel on it. It might not work at all since it's so thin. It will supposedly get here May 27.
 
The tabs on pouch cells are typically aluminum for the positive, or sometimes nickel-plated aluminum. The negative tabs are copper core with nickel-plating. The nickel is to reduce oxidation, but I think if you put an additional nickel strip along both sides, and pinch them with the spot-welding probes, I am fairly sure they would bond well.
 
if anyone wants to do this i highly recommend using nickel plated steel
i can weld 0.1mm copper at 1000A and it's really good welds, pure nickel doesnt stick at 1000-1300A
the only downside is it sparks alot, so wear eye protection. pure nickel doesnt spark

thanks author for good info
 
How much current are you able to pull by using 0.15mm copper using this strategy?
I want to make a 16s11p or 12p with 21700 pack using the p42a molicel. Those cell claim 45amp discharge. I plan to draw pulses at 30amps max per cell which would be about 330a or 360a. Has anyone doing this been able to push this kind of current? I don't think i saw or read anyone mentioning what current they are able to push using copper/nickel sandwich vs only nickel.
 
Not a whole lot to contribute here (planning on changing that in the coming weeks) but I've joined the copper club. I'm successfully welding copper to both anode and cathode of throwaway 18650 cells, facilitated by a small portion of nickel of course.

My setup is quite simple and creating a strong sandwich weld came with not much effort or struggle. I'm using -

• 12v 51ah MX Powered Gel lead acid, abused and still cranking out amps.
• 12v Duralast Gold Solenoid from AutoZone, seems reasonably heavy duty
• Flexible welding cable with electrodes from a rather unimpressive but convenient, cheap, and small Amazon spot welder
•Timer relay, linked below also from Amazon. An easy, functional, and inexpensive timer. Straight forward to program, can do extremely short intervals to trigger the solenoid, single and multiple with the ability to adjust on and off times between
pulses. No affiliation, just the link.

https://www.amazon.com/dp/B07RGT5G1X/ref=cm_sw_r_cp_awdb_imm_PS9CENK54GEBT4GXF920?_encoding=UTF8&psc=1

•Pure nickel strip, 7 x .15mm as well as 7 x .10mm.
•Pure copper sheet, .10mm thickness.

Really just a standard DIY spot welder, the same as every other DIY setup on YouTube, instructables, etc...

I was unable to create a weld that ripped the copper around the weld area, a proper strong weld, with a single pulse firing from my setup. Programming the timer for up to 25ms, but felt uncomfortable going any longer as this is a powerful rig. The success came when programming the timer for two pulses.

Footswitch -> 10ms ON -> 4ms off ->10ms ON

Had success with both .10mm and .15mm nickel on top of the .10mm copper. The results are a weld requiring pliers and tearing the copper. The welds are left on the cell afterwards. I will get pictures up. But for the moment I can say the real success came with two short pulses, I could not get a weld with a single long pulse.
 
if the single long pulse did not deliver, it just means you need to get a bigger battery source for more amps, and possibly thicker electrodes/cables. ideal is the fastest pulse with most energy.
some high c lipo packs are a good solution, or what i did is banks of old 25r cells from fried ebike packs plus some other mongrel trash cells i had lying around from old cordless tool packs.

as for double pulse, i cant comment, but sounds good, as long as the cells arnt taking heat.
 
I did try the dual pulse method. Tried some different timings. But in the end, I found that the single pulse did a better job.
 
Putting my desktop CNC to work. Designed in Inkscape.
 

Attachments

  • IMG_20210614_024218502~2.jpg
    IMG_20210614_024218502~2.jpg
    137.4 KB · Views: 1,260
  • IMG_20210614_023955438.jpg
    IMG_20210614_023955438.jpg
    198.6 KB · Views: 1,256
  • IMG_20210614_071720772~2.jpg
    IMG_20210614_071720772~2.jpg
    316.2 KB · Views: 1,259
  • IMG_20210620_025111~3.jpg
    IMG_20210620_025111~3.jpg
    329.7 KB · Views: 1,265
  • IMG_20210620_123216~2.jpg
    IMG_20210620_123216~2.jpg
    520.4 KB · Views: 1,262
Has anyone tried to weld the copper sheet to a busbar when terminating the battery pack?
 
spinningmagnets said:
From Ian M Molina on facebook. 0.20mm copper sheet, 0.15mm nickel, kWeld at 60J

https://www.facebook.com/100000645165546/videos/pcb.908101586417740/229170929021460

photo
Any way for those that don't FB?
 
There is a very short video that looks exactly like any other kWeld video. Then, he shows that it is hard to pull the welded strip off of the cell, which leaves behind the welded points.

BatteryKweld1.jpg
 
Back
Top