Thanks for the kind words, guys!
I would love to tig them but I'd think the process would dump a TON of heat into the cell and I'd expect damage.
Ever touch a small piece of 1/8" after doing a 1" seam? HOT! I did a lot of 1/8"
aluminum in class, but nothing thin as the foils these tabs are made of, so they could require less heat. Maybe you could penetrate a puddle before the tab heats up, and "spot weld" it that way, but I am skeptical.
The TV show I mentioned, about a123 manufacturing the prismatics and packifying them, showed cells being joined and the process described it as laser-welding. IIRC, the cell zipped past a device and then two pieces of severed tab fell away... I guess that happens FAST, and doesn't dump heat. Surely amongst us battery geeks, we have some laser geeks who have the hardware and skills and want to give it a shot!
Now I need to work a new termination method for the packs. I used to crimp and solder an 8ga wire on there, but after dissecting solder joins made by myself and others, solder doesn't seem to stay bonded long-term. It gets up into the ends of my crimped/rolled tabs and keep them in place, but I can't count on it for actual conduction.
I am thinking (4) 14ga wires, each terminated in a 45a Anderson, for a total 180a rated throughput, and well able to handle 240a (15c). That is futureproofing, the max I would choose to run this chemistry at, but for right now it will be driving my Methods Controller @100a peaks. Anyhow, I thought I'd crimp in the wires with slivers of steel and some sacrificial aluminum, zap it and see if I can melt it solid. Hmm, wonder if solder would bond to the tabs while they are molten, if I used that instead of aluminum.