This is the Best Budget Battery Spot Welder Kit | 30 Pulse Modes | DH30 | DH20 | BIFRC | DIY Project - YouTube
Spot Welding for Lithium-Ion Battery Packs - Cell Saviors
Amazon.com : RCBDBSM Pulse Spot Welder Battery Welding Machine for 4 Rows of 18650 Lithium Batteries Battery Pack Work, Battery Spot Welder with Cooling System and Charging Testing Function : Tools & Home Improvement