Has anyone ever tried these copper strips. https://www.ebay.com/itm/133104900617
I wouldn’t. Pure nickel won’t oxidize when exposed to water or air. If any of the plating of those copper strips come off then the copper will be exposed to air and could eventually start oxidizing which is a no no for reliability and safety especially when it comes to strips. Pure copper braiding is different, but I am talking out of my ass
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They would be great for soldering…especially the .3 ones
I just wanna know if they can be spot welded
Seller calls it “patina, normal and unavoidable” 
You can avoid it by not buying cheap alternatives to quality pure nickel 
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it’s not about being cheap, for me, anyway.
Copper carries a crapton more current than nickel. This in itself is reason enough to explore it’s use in high powered batteries.
I know @Arzamenable and others have welded copper foil with nickel " sandwiches" (nickel above and below the copper) in high current batteries. The copper itself does not have enough resistance to generate the heat required for welding. Nickel plated copper might be the ticket. $0.02 USD
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Explore away and tell me when my packs won’t explode 
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We aren’t talking about lipo packs. If you have built your own battery using nickel plated copper please comment.
Are you insinuating lithium ion cells can’t catch fire?
“Explode” was figurative and faster to write than “catch fire, wreak havoc and destruction inside my board”
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People are successfully experimenting with kWeld and nickel-copper-nickel sandwiches, and just the other day a customer emailed me that he was welding nickel plated copper (0.1mm) with good success.
As per my research, they are safe when looking at an individual cells, the manufacturers have to go through numerous stress tests, including things like overcharging at high current and drop tests. Of course a cell can short itself out internally, but they are designed not to self ignite from that.
The problem starts when wiring them in parallel. If you have e.g. a 10P configuration, the good 9 cells will help the one that shorted internally into self destruction. That’s why Tesla later had started to add fuse wires to each individual cell. There is a good video from HBpowerwall (also featuring my welder ;-)) which shows this: https://www.youtube.com/watch?v=PenPYwa00CA&t=685s
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Its much harder and imo not worth it
Anyone tried spot welding aluminium?
nickel plated copper is the gold standard in battery pack design in consumer products right now. It generally costs more and is harder to weld but if your building high performance packs then its the best option for reducing heat losses. Many large companies are using this nickel plated copper in production already.
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But not with hobby welders 
Need 220 and huge machines. .1 copper is the same as 2 layers of .2mm nickel
I’ll revisit, but .2 copper is a no go on kweld even 200j
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In a traditional sense, to just spot weld aluminum to aluminum you need to put steel below the electrodes with the desired aluminum pieces in between. The steel won’t weld to the aluminum because it can’t. Sooo, with regards to battery’s how you gonna weld a nonferrous to a ferrous metal? Aluminun strip to steel can?
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It’s the opposite man, pure copper conducts miles better and cooler than nickel.
If this item is properly done with pure copper core and pure nickel plating, this is an upgrade not a cheap downgrade!
Ah I’m late to the party. Please carry on!
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That’s what I was thinking but I’d need a super powerful welder to do it
I’m not saying anything against pure copper. There’s a reason it has value 
I’m speaking against plated materials. The ad doesn’t even state purity of either nor if other impurities were used and incorporated for a better adhesion of that plating. Plated can flake once the copper underneath and on the edges you’ve cut becomes too oxidized
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You can go pure nickel or pure copper. But going in between is a grey zone and asking for finding a new problem
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