DIY Spot Welding machine for battery packs
From wikiluntti
Introduction
NE555
Transformer
Theory: NE555 based
Idea
The 555 timer circuit controls MOSFETs that deliver short, high-current pulses for welding nickel strips. The 555 shall work in monostable mode.
The MOSFETs (IRLB4132 or IRF3205) handle the high welding current.
References
Some references related to 555 based
https://hackaday.io/project/204777-diy-battery-spot-welder-build-your-own-power-pack/details
https://www.instructables.com/DIY-Battery-Spot-Welder-Build-Your-Own-Power-Pack-/
pcbway.com/project/shareproject/