Lithium Ion Battery Solar Charger Design and Simulation

The work of the charger for lithium-ion batteries requires accuracy in performance, so charging must start at a voltage level commensurate with the battery voltage and with a constant current to avoid the battery’s temperature rising, which causes a reduction in its life. Exceeding the permissible limit will cause damage to the battery. In this work a smart charger for Li-Ion battery designed and simulated. The proposed charger supplied from stand-alone PV array, and that required to control both MPPT and battery charging in same time. The charging sequence starts with constant current charging mode CC, when the SOC reaches specific value then the charger changes the charging mode into constant voltage mode CV. In CC mode the PV array supplies its maximum power to the battery, while in CV mode the PV array supply a power equal to the battery charging capacity in the CV mode. Simulation results shows that the system efficiency is near 95% in all studied cases. The proposed system can operate in same efficiency even in variable irradiance level.