DIY BATTERY CHARGER (charger ng loptop pweding gamitin sa battery ng motor at kotse)

[@serge8]

As I can see, you are using an incandescent bulb as a current limiting resistor. Good!
The laptop charger should provide a DC of about 19V.
But using alternating current (AC), you can make a circuit to restore the battery from sulfation. To do this, you need just same incandescent lamps and a diode.
The first lamp, diode and battery are connecting in series. The lamp limits the current, the diode passes electricity only in one direction towards the positive terminal of the battery. As a result, the battery receives only the positive half cycle of the alternating current. The negative half-cycle is not passed by the diode.
Now let's change the schema. Let's connect the second lamp (lower power) in parallel with the diode. What will happen now. The positive half cycle works the same, but the negative half cycle now causes the battery to discharge through both lamps. In this case, the charge current is greater than the discharge current, the battery is charging with desulfation. PbSO4 cristalls is slowly dissolving in this mode.