A universal battery charging algorithm for Ni-Cd, Ni-MH, SLA, and Li-Ion for wide range voltage in portable applications

This paper presents a wide voltage range universal battery charging algorithm to meet the specification laid down for the 2007 Future Energy Challenge Competition sponsored by IEEE Power Electronics Society and Power Sources Manufacturers Association. A thorough study of the battery chemistries is carried out. A suitable universal battery charging algorithm is proposed based on the battery characteristics analysis. The proposed system is capable of charging Ni-Cd, Ni-MH, SLA, and Li-Ion from 2 V to 18 V of batteries. Ni-MH, SLA, and Li-Ionpsilas charging profiles were obtained through DAQ and utilized it to build a simple algorithm, which is to detect the inflection point, threshold point, and termination point. The Atmega 88 8-bit RISC microcontroller is chosen to implement the battery charging algorithm, and the experimental results will be shown for to verify the proposed algorithm.