App note from Fairchild Semiconductors on power MOSFETs selection including thermal design and usage on fast chargers. Link here (PDF)
The demand for battery capacitance up to 10,000mAh in mobile devices is steadily increasing as devices consume more power and offering more functionality. Large battery capacity provides longer battery run-time, but needs more time to charge. This application note describes how to decrease charge time and the impact of power MOSFET selection, including a practical design example. The one serial and three parallel (1S3P) 9,700mAh Li-Ion battery is used and 1C and 0.5C rates are set to measure charging and discharging time, respectively. Products that require large battery capacitance and fast charging time include tablet/notebook docking stations, portable music players, and commercial electronic Point-of-Sale(POS) systems.