Review on SUNKKO 737G+ Battery Spot Welder, Pulse Welding Machine for Lithium Battery Pack, Compatible with 18650 and 14500 Batteries, Works with 0.35mm Nickel Strips, 110V by Kenny Sarma

Absolutely not suitable for welding nickel of any consistency over 0.15 mm. Even then, the weld barely holds the batteries. Worry about the vibrations tearing the welds, they're that bad. I contacted the company but they needed the original purchase receipts, welding videos, samples and settings that I used, then they didn't offer any help. I eventually found that the handles were the problem, so I had to buy a set of fixed welding electrodes to put more tension on the material. Apparently, the tension in the spring mechanism used on regular grips disappears.