Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Batteries, Chargers, and Battery Management Systems.
Post Reply
User avatar
tmho   100 W

100 W
Posts: 284
Joined: Jan 09 2011 3:25pm
Location: Richmond, BC, Canada

Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by tmho » Feb 21 2019 4:46am

I bought the Sunkko 737G+ spot welder (which should be quite powerful when compared with the other Sunkko models) recently for building my first diy battery pack. So far from my testing, at about 75% power setting, welding with 0.2mm pure nickel strips onto cells is no problem.

But for the series connection, if pure nickel strip is used for maximum current purpose, then that series pure nickel strip will be welded onto the parallel pure nickel strip. The seller had told me that pure nickel strip cannot be welded onto another pure nickel strip. But from youtube (https://www.youtube.com/watch?v=ublFs7IU05c&t=683s), I saw he welded pure nickel strips onto pure nickel strips easily with a Sunkko spot welder just at about 50% power setting. Therefore, I tried with mine at 75% power setting but I failed.

I have heard that Sunkko spot welder is not that reliable. I have not started welding my battery pack yet. I do not want it break down before I finish my pack, so before trying mine at 100% power, I would like to check here if anybody got successful experience in spot welding pure nickel strip onto another pure nickel strip, especially with Sunkko welders.

If that is not possible, for the series connection, I will try to use nickel plated strip first and then on top of the nickel plated strip I will weld another pure nickel strip. Is this a good way and/or possible way to increase the output current of my pack?

krlenjuska   10 W

10 W
Posts: 72
Joined: Feb 18 2019 4:50pm

Re: Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by krlenjuska » Feb 21 2019 4:58am

Have you tried to increase welding time?

User avatar
tmho   100 W

100 W
Posts: 284
Joined: Jan 09 2011 3:25pm
Location: Richmond, BC, Canada

Re: Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by tmho » Feb 21 2019 5:20am

krlenjuska wrote:
Feb 21 2019 4:58am
Have you tried to increase welding time?
I set the current at 80 and pulse at 12. I guess welding time is the pulse.

krlenjuska   10 W

10 W
Posts: 72
Joined: Feb 18 2019 4:50pm

Re: Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by krlenjuska » Feb 21 2019 5:42am

tmho wrote:
Feb 21 2019 5:20am
krlenjuska wrote:
Feb 21 2019 4:58am
Have you tried to increase welding time?
I set the current at 80 and pulse at 12. I guess welding time is the pulse.
Sorry i thought you have some potentiometer for welding time. I have home made spot welder with chinese controller and i can weld nickel to nickel without issues. I need more amps of course but no problem so far.

Try to increase pressure to your nickel if you can.

User avatar
tmho   100 W

100 W
Posts: 284
Joined: Jan 09 2011 3:25pm
Location: Richmond, BC, Canada

Re: Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by tmho » Feb 22 2019 2:46am

krlenjuska wrote:
Feb 21 2019 5:42am
tmho wrote:
Feb 21 2019 5:20am
krlenjuska wrote:
Feb 21 2019 4:58am
Have you tried to increase welding time?
I set the current at 80 and pulse at 12. I guess welding time is the pulse.
Sorry i thought you have some potentiometer for welding time. I have home made spot welder with chinese controller and i can weld nickel to nickel without issues. I need more amps of course but no problem so far.

Try to increase pressure to your nickel if you can.
Thank you. I will try that later.

User avatar
multifrag   100 W

100 W
Posts: 107
Joined: Feb 19 2016 5:44am
Location: London, UK

Re: Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by multifrag » Feb 22 2019 5:23am

Works with 709A. Mine required all pulses and the knob at 6-7. Don't forget that you get higher power right at the machine. So if the hand-held tool doesn't have enough ''chooch'', just weld with the tips at the front of the machine.

hemo   100 W

100 W
Posts: 160
Joined: Mar 30 2016 5:13pm
Location: England, GB ( UK).

Re: Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by hemo » Feb 22 2019 6:39pm

Why bother with Sunko's, just get an Arduino lipo welder to do the business.

User avatar
tmho   100 W

100 W
Posts: 284
Joined: Jan 09 2011 3:25pm
Location: Richmond, BC, Canada

Re: Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by tmho » Feb 23 2019 2:17am

tmho wrote:
Feb 22 2019 2:46am
krlenjuska wrote:
Feb 21 2019 5:42am
tmho wrote:
Feb 21 2019 5:20am
krlenjuska wrote:
Feb 21 2019 4:58am
Have you tried to increase welding time?
I set the current at 80 and pulse at 12. I guess welding time is the pulse.
Sorry i thought you have some potentiometer for welding time. I have home made spot welder with chinese controller and i can weld nickel to nickel without issues. I need more amps of course but no problem so far.

Try to increase pressure to your nickel if you can.
Thank you. I will try that later.
Today, I tried spot welding 0.15 pure nickel strip onto another 0.15 pure nickel and the result is acceptable. The setting was pulse 10, current 70. Last time I failed and the setting was pulse 12 and current 80, which was a higher power setting. I guess this is because today I have followed your suggestion of increasing the pressure.

Today, I have also tried spot welding 0.2mm pure nickel strip onto another 0.2mm pure nickel strip. The result is not okay and the setting was pulse 14, current 80. I may try using higher power later when I have time.

User avatar
tmho   100 W

100 W
Posts: 284
Joined: Jan 09 2011 3:25pm
Location: Richmond, BC, Canada

Re: Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by tmho » Feb 23 2019 2:20am

multifrag wrote:
Feb 22 2019 5:23am
Works with 709A. Mine required all pulses and the knob at 6-7. Don't forget that you get higher power right at the machine. So if the hand-held tool doesn't have enough ''chooch'', just weld with the tips at the front of the machine.
Thanks for your reply and suggestion. Please advise the thickness of the pure nickel strips you used.

User avatar
multifrag   100 W

100 W
Posts: 107
Joined: Feb 19 2016 5:44am
Location: London, UK

Re: Can Sunkko spot welder be used to weld pure nickel strip onto another pure nickel strip?

Post by multifrag » Feb 23 2019 1:37pm

tmho wrote:
Feb 23 2019 2:20am
multifrag wrote:
Feb 22 2019 5:23am
Works with 709A. Mine required all pulses and the knob at 6-7. Don't forget that you get higher power right at the machine. So if the hand-held tool doesn't have enough ''chooch'', just weld with the tips at the front of the machine.
Thanks for your reply and suggestion. Please advise the thickness of the pure nickel strips you used.
Usually 8x0.15, but used 8x0.20 also.

Post Reply