Auto Cut OFF 12 volt Battery Charger Circuit | 12V Battery Charging & Auto Cut Circuit

When the vehicle is started, without the introduction of a load (the lights, ceiling fan, or air conditioner), the volts will usually rise to an average of 14v. If the multimeter reads at more than 14.8v, then this can be considered an overcharging system.

But in general, it can take anywhere from 30 min to 1.5 hours to fully charge your Android smartphone, depending on the 12V battery capacity of your device. The larger the capacity, the longer it takes to charge the system.

When a deep cycle battery is fully charged, it typically reaches a voltage of around 12.6 to 12.8 volts. However, the voltage can temporarily rise to around 13.2v during the charging process unit. As long as the voltage doesn't consistently exceed 13.8 volts, it should not be a cause for concern for battery Health.

For standard passenger vehicle 12v systems, anything above 14.8v is worrisome. Anything below 13.6v will not adequately charge the battery charging voltage of 15V.

A 13.6V reading at rest would indicate a newer, fully charged lithium iron phosphate battery 12V battery. while older units might read 13.5V. As soon as they have any draw at all, this Fig (Circuit diagram) falls away quickly. A 99% charged battery will read 13.4V, and a 93% charged battery will read 13.3V battery level.