Smart Auto Cut-Off Charger for Safe and Efficient Battery Charging

Dr.T.Agitha, Mr.K.Kamalamaharaja
1Assistant Professor, Department of Biomedical Engineering, Vivekanandha College of Engineering for Women (Autonomous)
2Assistant Professor, Department of Biomedical Engineering, Vivekanandha College of Engineering for Women (Autonomous)
Corresponding author: agitha@vcew.ac.in

ABSTRACT

An automatic cut-off charger is an intelligent charging system designed to prevent overcharging of rechargeable batteries by automatically disconnecting the power supply once the battery reaches its full charge level. Overcharging is one of the major causes of battery damage, reduced lifespan, overheating, and safety hazards such as leakage or explosion. When the battery voltage reaches a predefined threshold corresponding to full charge, the system automatically cuts off the charging current. Once the battery voltage drops below a certain level due to usage, the charger can resume charging automatically, thereby maintaining optimal battery performance.

The system can be implemented using analog circuits or digital control methods. In analog designs, operational amplifiers and comparators are commonly used to detect voltage levels and trigger switching elements such as relays or transistors. In digital designs, microcontrollers provide more flexibility and accuracy by enabling programmable voltage thresholds, charging profiles, and real-time status indication through LEDs or display units. Advanced designs may also incorporate features such as temperature monitoring, short-circuit protection, and fast-charging capability.

Keywords— Charging, Battery charge, Degradation of battery, Auto cut-off, Sensors, Programmed controllers, Track the power level.