Electrochemical properties of Cu6Sn5 alloy powders directly prepared by spray pyrolysis

Spherical shape Cu–Sn alloy powders with fine size for lithium secondary battery were directly prepared by spray pyrolysis. The mean size and geometric standard deviation of the Cu–Sn alloy powders prepared at a temperature of 1100 °C were 0.8 μm and 1.2, respectively. The powders prepared at a temperature of 1100 °C with low flow rate of carrier gas as 5 l min−1 had main XRD peaks of Cu6Sn5 alloy and copper-rich Cu3Sn alloy phases. Cu and Sn components were well dispersed inside the submicron-sized alloy powders. The discharge capacities of the Cu6Sn5 alloy powders prepared at a flow rate of 5 l min−1 dropped from 485 to 313 mAh g−1 by the 20th cycle at a current density of 0.1 C. On the other hand, the discharge capacities of the Cu–Sn alloy powder prepared at a flow rate of 20 l min−1 dropped from 498 to 169 mAh g−1 by the 20th cycle at a current density of 0.1 C.