18650 spot welding -how to- ULTIMATE REPOSITORY

[Cowardlyduck]

hi is want to learn how to spot weld 2 layer pure nickel 0.15 on top of each other for my battery. possibly will be using kweld.
is this topic covering everything i need to know before doing my first test without danger? if not could someone point me wich thread would be better covering 2layer nickel spot welding ? thx

You just weld it on top like normal. I usually find I need to increase the weld time as I add more layers.
This video shows how:
[youtube]R8NgGlP6k38[/youtube]

Cheers

 

[spinningmagnets]

Please investigate nickel/copper sandwich, before welding nickel buses.

 

[Cowardlyduck]

Please investigate nickel/copper sandwich, before welding nickel buses.

I did, and thank you! I wasn't aware of that before. Found this:
https://www.electricbike.com/introduction-to-battery-pack-design-and-building-part-3/
And this from the link above:
[youtube]4dZTGAcFmtA[/youtube]

This is great, I will definitely look at switching over to this method for higher power stuff.

Thanks again!

Cheers

 

[want to build]

hi is want to learn how to spot weld 2 layer pure nickel 0.15 on top of each other for my battery. possibly will be using kweld.
is this topic covering everything i need to know before doing my first test without danger? if not could someone point me wich thread would be better covering 2layer nickel spot welding ? thx

You just weld it on top like normal. I usually find I need to increase the weld time as I add more layers.
This video shows how:
[youtube]R8NgGlP6k38[/youtube]

Cheers

hum by d to increase the weld time as I add more layers.;; what do you mean cause how long and does the heat goes a lot in the cell? cause i have seen tin lead solder with thermal video and the ends of cell get really hot..

 

[want to build]

Please investigate nickel/copper sandwich, before welding nickel buses.

I did, and thank you! I wasn't aware of that before. Found this:
https://www.electricbike.com/introduction-to-battery-pack-design-and-building-part-3/
And this from the link above:
[youtube]4dZTGAcFmtA[/youtube]

This is great, I will definitely look at switching over to this method for higher power stuff.

Thanks again!

Cheers

hi i watched the video carfully and i really didnt see any difference( ok im new).
at first he says spot welding effect is good what does he mean by spot welding effect?

then he says spot welding effect is general? what does he mean and do you guy see a difference compared to the @good@ , i didn't
tx

 

[Cowardlyduck]

hum by d to increase the weld time as I add more layers.;; what do you mean cause how long and does the heat goes a lot in the cell? cause i have seen tin lead solder with thermal video and the ends of cell get really hot..

I can barely make it out, but what I think your asking is why doesn't it make the cells get hot when increasing the weld time and how does this compare to soldering.
Well to answer that...no amount of spot welding time will even come close to the amount of heat cells absorb when soldering, so not even a comparison.
Also, the easy way to figure out how much you need to increase the weld time is to just try it...if after adding more layers it won't stick, add more time to the welds until it does.

hi i watched the video carfully and i really didnt see any difference( ok im new).
at first he says spot welding effect is good what does he mean by spot welding effect?

then he says spot welding effect is general? what does he mean and do you guy see a difference compared to the @good@ , i didn't
tx

The main thing to note is what you can see in that video. When he tries to remove the weld you can see that they stick. That's what really matters.

Cheers

 

[want to build]

very helpfull thank you . that was my question indeed.

 

[Hummina Shadeeba]

the link to the main data on the first post doesnt work for me

 

[Silvaticus]

That explanation makes perfect sense, thanks.

On the topic of the probes wearing, I suspect I'm either doing something wrong or my probes are of particularly low quality because they seem to be wearing far faster than I assumed they would do. I figured a quick video showing exactly what's happening would be easier than me trying to describe it, so here you go.

This is 0.2mm pure nickel on a INR18650-30Q that I'm just using for practice. The welder is set to 40ms with a 20% preheat (the Sequre 100% rips off the functionality from the Malectrics from what I've read). The battery is a Turnigy 5500mAh 140C 3S2P pack.

Any tips etc. welcome!

[youtube]jLx-BYhHOJ4[/youtube]

The shape of the contact point is not close to a full circle.
The contact area is constantly changing depending on how you position the electrodes.
Clear traces of metal overheating are visible at the welding points.
Such points are mechanically weaker. They have a high risk of corrosion from these locations.
In addition, an electric arc occurs between the electrodes and the surface.
You have too long a welding pulse and / or insufficient current.
In most cases, to get good quality welds you should fit within 20 ms intervals.

 

[Silvaticus]

What's out there that can handle 0.2-0.3mm pure nickel, including stacked for the parallel/series connections? Is my only option to play the QC lottery with Sunkko units?

Stop even thinking about 0.3 nickel. It is extremely difficult to weld even with very powerful machines. kWeld will never handle it. Choose 0.2, which is sufficient for most tasks. Do not even think about buying a Sunkko 737 with an efficiency of 25-30%, this is wasted money. You can try your luck with Sunkko 709 (it is better than 737) but its limit is 0.15 nickel.

Right, I've now got my Sequre SQ-SW1 welder

Does he really weld? Looks like a toy.

One issue I'm finding is that when I pull the nickel strip off to check the welds, sometimes it will only rip a hole at one point, not both. What might be causing this?

On DC welder current flows from the positive electrode to the negative electrode. Below the negative electrode, the temperature is lower and the welding core is smaller.