Automatic 12V Battery Charger Circuit

Hello friends, on this occasion, I will share tips on how to make an automatic circuit to recharge a 12V battery or a motorbike/car battery that can be on / off automatically when the battery is under voltage it will automatically drain and charge off when the battery is full. Next is the circuit scheme of automatic 12V battery charging or Accui:

The workings of the circuit above use IC 555 as a voltage detector from the battery that goes to pin 2 IC 555, when the battery is in a state of voltage that is precisely at 11.8V, the trigger pin is also not filled so the output of IC 555 will be voltage + so turn on the Relay and charger will be connected by a 12V battery, and when the battery voltage is full at 13.8V then the Pin Threshold (6) will be charged and the output voltage will be - and the relay will be disconnected instantly the charger is not connected, the charger connector on J2. And to add a voltmeter display you can also add on the J3 Header pin. The battery connector is on J1 Terminal Block. To simplify the assembly I provide a PCB Layout diagram with 2 layers as shown below:

To adjust the on/off relay you must calibrate yourself on R3, R4, R5, and R6

To simplify PCB creation you can download PCB Layout Gerber along with BoM (Bill of Material) below:

PCB Layout Automatic 12V Battery charging.gerber
BoM Automatic 12V Battery Charger