Testing out a $20 Amazon spot welder for nickel strap on batteries.
Love the product descriptions
"Havcybin Welding Machine Pen DIY Portable12V Battery Storage Spot Welder Pen PCB Circuit Board Welding Current for 18650/26650"

Spot welder link
https://a.co/d/gXQln0p

12v Battery link
https://a.co/d/efetun9