JP spot-welder, FET-switched, timed adj. pulse

Guys, does anyone have a alternative to riva's jp spot welder? I am very envious of you guys that have one... As all I can find are Chinese sunko's that have mixed reviews- actually mostly negative. Looking for something with a welding pen to use on an irregular shaped pack. Any suggestions are greatly appreciated
 
Quokka said:
Guys, does anyone have a alternative to riva's jp spot welder?

Any alternative to the JP Welder is a downgrade :lol: Sorry, I could not resist. It is sad that the welder is not available at the present but riba's health is way more important and I really hope he gets well soon.
 
Quokka said:
Guys, does anyone have a alternative to riva's jp spot welder?

Did you see my post earlier in this thread: https://endless-sphere.com/forums/viewtopic.php?p=1160937#p1160937
I am not affiliated with this project in any way (Because someone already asked me if I sold that welder ;) )

Cheers, Ulli
 
Quokka said:
Guys, does anyone have a alternative to riva's jp spot welder? I am very envious of you guys that have one... As all I can find are Chinese sunko's that have mixed reviews- actually mostly negative. Looking for something with a welding pen to use on an irregular shaped pack. Any suggestions are greatly appreciated

If you have skills in electronics, I will soon post my welder as open source.

@ mistercrash - thanks :D
 
Adruino Timer Microwave Transformer Battery Tab Werlder from a gentleman out of England. Works on either 120 or 240V, just a different mini transformer on the PCB. You just plug it into the wall outlet and thats it.
http://www.avdweb.nl/tech-tips/spot-welder.html
I just did one myself and it is good.

No need for automotive batteries, no need to hold electrodes in your hands. Always consistent pressure.
I got my transformer out of a 1500W microwave at the back of a Thrift Store called Value Village. They cant sell them, and people use their drop-off as a dumping ground. Its the cost of doing business for them. I however didnt be a bum and re-dump them there, the country land-fill accepted them with no cost to me. Its good to know. I am not sure about the metropolitan dump, there might be a weight fee.

Simple soldering of through hole components. Can buy soldering irons for cheap. I bought mine for $10. It took about an hour or so. If you have any questions just give me a PM. I can take some pictures of my unit. All in all I think the cost of the parts came to $50 for the stuff from the english guy, and another $20 for the electronic parts from mouser.com, I got free shipping on my order from mouser. Local electronic parts stores would sell these basic components as well, thats if you are in any decent sized city.
 
From the DIY spot welder website
Electrical data

  • Weld current: 1100A or 400A
  • Open voltage: 2.6V
  • Mains current during the weld pulse: 14A
  • Quiescent current: 1.6A

Maximum welding thickness
Light duty portable spot welding guns have a welding current of at least 4000A, which allow welding of 2 x 1mm low carbon steel sheets. The DIY spot welder just delivers 1100A, which is fine for welding small electronic parts. Although I have seen that people have welded 2 x 0.75 mm sheets with this kind of spot welders.

Battery tab welding parameters

For nickel plated steel strip of 0.15mm thickness, this is used most.

  • Weld electrode force 400g (4N)
  • Weld pulse time 100ms
  • Current 1100A
  • Electrode diameter 1.5mm
  • Electrode outer distance 5mm


Do you think this will be able to do 0.2mm thick nickel strips?
 
I have been welding whatever batterysupports.com sells. I think its 0.15. Their website seems to be down.

OK OK My bad, reading below the gentleman is not in England, but in Belgium.
Sorry.
 
Battery-tab.JPG


Weld pulse time of 100ms seems way too long and would transfer too much heat to the cells me thinks. I don't get the rainbow of colors from heat shown in this pic even welding .3 Nickel with the JP Welder.
 
macribs said:
From the DIY spot welder website
Electrical data

  • Weld current: 1100A or 400A
  • Open voltage: 2.6V
  • Mains current during the weld pulse: 14A
  • Quiescent current: 1.6A

Maximum welding thickness
Light duty portable spot welding guns have a welding current of at least 4000A, which allow welding of 2 x 1mm low carbon steel sheets. The DIY spot welder just delivers 1100A, which is fine for welding small electronic parts. Although I have seen that people have welded 2 x 0.75 mm sheets with this kind of spot welders.

Battery tab welding parameters

For nickel plated steel strip of 0.15mm thickness, this is used most.

  • Weld electrode force 400g (4N)
  • Weld pulse time 100ms
  • Current 1100A
  • Electrode diameter 1.5mm
  • Electrode outer distance 5mm


Do you think this will be able to do 0.2mm thick nickel strips?

I bought one of these bad-boys Arduino timers and they work really well as far as the timing is concerned.
Unfortunately, there is a lot more to a good weld than just an accurate and flexible timer.
I had previously bought one of the Chinese, under powered Sunkko 788 units and it lasted enough for one battery pack. Then it broke.

So, I purchased the timer from the guy in Belgium (avdweb.nl) and one of these spot welders (the 240 volts):
http://www.harborfreight.com/240-volt-spot-welder-61206.html

And replaced the guts of the Sunkko with the timer and the transformer from the HF spot welder.
Plenty of power (had to replace the secondary windings on the transformer, as the 1.8 volts from the single turn from the factory was not enough) and I can weld very well but only up to 0.15mm pure nickel. (4 to 5 ms is all it takes)
But if I try 0.2mm, I get sticking electrodes no matter what I use. I have tried multiple alloys made for spot welding and different copper alloys, but they stick more or less the same. Even tried the Sunstone Engineering recommended part for battery spot welding and got no relief. The problem with sticking electrodes is a bit better when using steel covered with nickel but I don't want to use that material.

Even bought one of these:
http://www.aliexpress.com/item/Lith...se-for-high-power-spot-welder/1710846906.html
Biggest piece of manure I have seen in a while. The idea is OK but too cheaply implemented and made for a very low welding power.

Now, it could be the electrodes on the old Sunkko not being designed well and not capable of delivering the current needed for a good weld with thicker nickel and I am about to find out: I am almost done building a set of hand-held electrodes (with springs build-in to equalize the pressure as well as the tips held in place at the optimal gap. With them and the JP welder, I am hoping to get that hard-to-get, perfect battery tab weld.

I will post pictures soon when the work is finished.
 
Ok, I finished my project!! :mrgreen: Welding 1296 Batteries(18650 Samsung 29E) with the JP Spotwelder. Welded 5250 times. No problems at all. The pack is now 36S36P. It gives my electric motorcycle an awesome range close to 150 km.
Riba, thank you very much for this easy to use great peace of art. :D


 
I always seemed to get some sticking when it was making good welds. Rocking the tip or twisting it would break it loose easily. With handheld electrodes, this is easy in practice. I'm not aware of a good way to completely prevent sticking. It seemed if the contact was a bit poor, sticking was more likely. Cleaning the nickel first seemed to help.


I'd like to see a pic of a 36s,36p pack :twisted:
That's like 10x bigger than my bike pack.
 
fechter said:
I always seemed to get some sticking when it was making good welds. Rocking the tip or twisting it would break it loose easily. With handheld electrodes, this is easy in practice. I'm not aware of a good way to completely prevent sticking. It seemed if the contact was a bit poor, sticking was more likely. Cleaning the nickel first seemed to help.

There could be a lot of reasons for sticking electrodes. Sticking means the electrode material is molten and has become part of the weld itself, which it isnt supposed to.

Main reasons:
- too little weld pressue
- uneven weld pressure
- contaminated electrodes
- contaminated material
- wrong/molten eletrode material (plain copper is just not up to the job)
- wrong current/power settings
- wrong timer settings, upslope, downslope, hold and squeeze settings

You have to try different settings starting from the bottom-up.

Paul
 
fechter said:
I always seemed to get some sticking when it was making good welds. Rocking the tip or twisting it would break it loose easily. With handheld electrodes, this is easy in practice. I'm not aware of a good way to completely prevent sticking. It seemed if the contact was a bit poor, sticking was more likely. Cleaning the nickel first seemed to help.


I'd like to see a pic of a 36s,36p pack :twisted:
That's like 10x bigger than my bike pack.


Maybe you should use stronger battery with shorter pulse.

@meridiaan - impressive :)
 
My battery was very marginal for the job, so that may be the main issue. It wasn't a big deal, just something to work around.
I noticed with more pressure, it had less tendency to stick and keeping things clean helped.
 
Don't connect the diode backwards.
It doesn't go well.
Fires will ensue.
I've welded thousands of batteries and handled 15k+ Model S cells and this is first (accidental) fire :-D

1nOfLPb.jpg
 
okashira said:
Don't connect the diode backwards.
It doesn't go well.
Fires will ensue.

Yikes!

Hopefully the board will be repairable. I've thought about using a fuse or fusible link, but figured it would add too much resistance. Maybe the diode wire should be sort of skinny.
 
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