Battery Charger
This circuit is a bit advanced but simple charger.
The supply voltage comes from an AC household power supply at 230V RMS or 325v peak to peak
The AC is stepped down from a Transformer to around 13.2v RMS sine wave output at 60Hz. It is then rectified by a full Bridge configuration diode to convert from AC to DC.
It is then fed to a capacitor to have a smooth DC supply magnified to 20.6v DC at Capacitor junction. An inductor follows the output of the capacitor to maintain a stable current source Voltage and current.
Most Standard 12v battery can be at full capacity up to 14.2v
Hence, A Zener diode is placed after the Inductor to control or limit the charging voltage not to exceed the full charge voltage ⚡ of the battery at 14.2v.
When the battery reaches or exceeds its full charge voltage, it then starts to discharge and maintain until it goes back to full charge rate at 14.2v.
Note: As a safety, we can reduced zener limit to 13.2v or even lower to accomodate old batteries that are. unable to reach 14.2v full charge
To simulate, lower the battery voltage to a say 9v then gradually increase it to full charge voltage at 13.2v and see how the voltage increases and the current decreases as the voltage approaches full charge status.
