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Part 3 - Spot welding vs soldering, spot welder comparison, flat pouch cells, and tips from the former head battery engineer at Zero motorcycles (don't flash vaporize the electrolyte and melt the separator when spot welding to the negative can and contaminate the electrolyte)
Another guide on building a simpler e-Bike pack: http://www.ebikeschool.com/how-to-build-a-diy-electric-bicycle-lithium-battery-from-18650-cells/
Spot Welding:
K-Weld build thread on Endless Sphere
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