Design and Implementation of a Fully-digital Lithium-Ion Battery Charger

The rapid progress in developing computer and communication systems promotes the design trend of portable electronic apparatuses, which are light, thin, short, and small. These developments have also resulted in massive demand for secondary batteries. The advantages of lithium-ion batteries include no memory effect, high operation voltage, and high energy density. Therefore, they are the most popular secondary batteries for consumer electronics. This paper presents the design and implementation of a FPGA-based lithium-ion battery charging system. To obtain the optimal charging performance for the lithium-ion battery charger, a multi-phase converter is used in the proposed system. Using this topology, the performance of the proposed system can be raised. In addition to the hardware, a graphical user interface is also proposed in this paper. Simulation and experimental results validate the effectiveness of the proposed charging system. According to the experimental results, the proposed charger is capable of charging the lithium-ion batteries with less than 1% current ripple