At a glance we can see the major components you’d expect in a discharger: a fairly simple PCB, four ceramic power resistors, a holder for a single 18650 ... device a battery charger, [Jasper ...

The same holds true for battery power ... ll want a charger circuit. The little circuit fits on top of a standard 18650 cell and uses two chips (one of which is just a dual MOSFET) and three ...