Added the smart spot welding program, removed the bottom and gave up the trigger switch, and used the program to automatically control the spot welding action. When the soldering pen touches the nickel sheet, the spot welding pulse is automatically output Do whatever you want No need to press the switch At the same time, the delay point is abandoned. Welding mode Everything is left to the program, free your hands, and really achieve the effect that you can click  Upgrade from the original third gear to the current 5 gear. This can better adapt to different batteries, and batteries with lower performance can also be spot welded. At the same time, it is also suitable for more convenient scenarios, with different nickel sheet thicknesses. There can be more gear choices  The structure of the board has been optimized, and the circuit design is more reasonable The MOS tube driving part of the board is designed with bold and tinned, which effectively reduces the resistance and increases the overcurrent capability  Added 4 screw holes, suitable for installation in a small box, The circuit board of this spot welding machine can be used for welding 18650/26650/32650 lithium batteries. Advantages: portable, stable, reliable, and durable. Low cost, you have a car starter battery, or a high-power battery pack, just connect it and you can use it It saves production costs  Users need to bring their own 12V battery for power supply, the welding current is about 100A~200A, and it is easy to weld the common 0.1mm~0.15mm nickel plated sheet. Please make sure that your battery can have a current greater than 100A, otherwise you will not be able to weld Power supply voltage: 12V-15V Working current: 100-200A (discharge below 100A, it will not work.)