Do you really have to hand-build a spot welder to hand-build Li-ion packs? Don’t take my detour — see what you make of this one

Building a car jump starter from supercapacitors + lithium cells — the cells store energy, the supercapacitors deliver the big current; 21700 4000mAh cells in 2P4S, 2.7V 360F supercapacitors, two together should push past 100A instantaneous, CCA estimated 500+, should start a 2.4L car; final assembly and test next

Honestly, I haven’t figured this spot welder out — 9.9 gears, and 0.1 nickel strip only needs gear 1.5 to 1.8! I haven’t figured it out and you’re still buying it after me, unbelievable

Boston 5300 Li-ion 24V 8P6S pack picked up at a scrapyard, repaired successfully — but no BMS; ordered one online and will test capacity when it arrives

Hand-built monster fan

Hand-building a thruster Li-ion pack,

Ep. 31 | Very ‘open for business’, good morning, a workhorse’s daily grind, energy +1 — hand-building a 2S2P flashlight pack for the Wurkkos SP10 and other 8.4V flashlights

Ultra-low-voltage coilgun: the most powerful coilgun with the least copper

Immersive build, 12V high-capacity pack from Sony C6 high-drain cells — with a spot welder you need nobody, done in minutes