PM me about those testers? Size, capacity and prices 
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These look awesome. Just a question in regards to the nickel. Is it possible to get slits cut in the nickel. Most peoples spot welders will struggle with. 3 if its not cut. Or maybe get the nickel made in 0.15 aswell so people can stack it if there spot welders can’t do the job.
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Welcome. Level matched to Builder’s Forum. Carry on.
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My English not so good. How can do?
There will be slits in them if it’s this what you mean 
I doubt that no one had tried to pull off the nickel from the pcb
If no one has, Im glad to do it, send me a pcb I will weld 0.2mm nickel to it with my kweld and post the results
These discussions are starting to get kinda annoying, everyone is talking but it seems to me that most of the people here didnt event hold the pcbs in their hands
Also why complicate things again?
Just calculate the volume of a 10/12awg wire and try to put that same volume in the pcb trace thickness and it should be more or less the same
Or even simpler solution is just to solder some wire on the pcb trace and stop this nonse…
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Could just put multi strand on 12 pcbs as U say but when going for the easiest and most efficient way and you like to dork out on it…
I’ve welded to the pcb many times and and it isn’t too easy to rip it off but when the goal is to do it the best way and also get people to use these with minimal tools an iron seems it
.But still how to get bare cells with just tabs welded on already? That’s needed and no one is selling them even though it’s the only way to ship welded cells that is legal. This could be the easiest quickest safest legal diy battery.
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In EU NKON will weld tabs on any of their cells for you in either C or S configuration.
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I think the issue with NKON is that the tabs are too thin aren’t they? Unless there’s something I’ve missed, it’s been discussed a few times on builders.
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It would work like single cell fusing, should be ok. The current is then distributed evenly into the pcb
I’m no current expert so I’d leave that stuff up to you but I’ve always looked longingly at the tabbed nkon cells 
The tabs are designed to carry the load of a single cell and not the entire P-group, so in order to properly use them you need to solder/spotweld them to a pcb, solid copper bar, flat braided wire or whatever you want.
If the current of the tab is exceeded (single cell malfunction) the tab would burn and cut off the load, thus preventing a thermal runaway.
nkon:
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Sorry about hijacking your thread Frederik 
So implementation of pcb’s and tabs from nkon theoretically make batteries much easier to build and add free cell level fusing?
Sign me up.
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Not so true 1.5 by 8mm our Nickle will start to heat up at 4.9 Amp
8 by 0.15 is aprox 1.2mm2
copper carrying 19 amp ish will be at 70deg c in a air temp of 35 deg C and coppers a much better conductor than Nickle 3 and a bit times better.
You rate Battery packs according to its weakest point. 1 little Nickle tab is a week point it adds resistant that heats up. To much heat is just bad for electrics and battery’s and carying current, voltdrop. Down to a balance of how much heat and reduced life you think is acceptable.
it seems 7mm wide is kind of a standard size for 18650 but you could use 12mm and .3mm thick.
copper is over four times as conductive as nickel
it would be nice to do a simple test putting current through with a power supply on the bench. I think the standards here (https://endless-sphere.com/forums/viewtopic.php?f=14&t=68005 ) are pretty conservative as well as matador’s. there’s the big variable of how long at the current and also the ability to get rid of heat. of course lower electrical resistance being the better performer beyond the safety concerns and better just to go bigger
It seems everyone is way under spec on these tabs and maybe people are following in the footsteps of ebikers where they generally aren’t pulling as much per cell, and cells are getting more powerful
extrapolating from niobie’s guide I posted a 12x.3 strip would be considered good for up to 16amps and acceptable up to 25amps.
Someone riddle me this
All these ampacity charts you guys posted, why doesn’t it mention the length of the wire/nickel strip in the data?
so 20awg is good for 10 amps? but over what length? a metre?
What happens if you are only using 5cm? can you pull 20 amps over a much shorter distance? these charts make absolutely no sense without knowing the length of the wires.
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The longer the wire, the more heat, but also more material for that heat to spread in. That is why length doesn’t matter.
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