Li-Ion Cell Discharge Unit for Accurate Battery Capacity Measurement

Lithium-ion batteries are integral to modern electronics, yet they are often marketed with capacities exceeding their true value. This paper presents the design and implementation of a Lithium-Ion Cell Discharge Unit for precise battery capacity measurement. The system uses constant current discharge controlled by a microcontroller, combined with an operational amplifier, MOSFET, and other essential components. Key innovations include PWM signal control, efficient heat dissipation, and a robust user interface via OLED display. Experimental results demonstrate accurate capacity measurements, critical for verifying battery quality and supporting reuse in secondary applications.