Si/Cu3Si/Cu composite material synthesized by low cost and high efficiency method as anode materials for lithium-ion batteries

Abstract In this work, submicron silicon(Si) particles obtained from ball-milling the broken crystalline Si wafers was modified with nanosized copper(Cu) particles by electroless chemical deposition. As-deposited Si/Cu particles was further annealed by rapid thermal process to attain beneficial Si Cu alloy at contact interface. The bare Si, as deposited Si/Cu and Si/Cu3Si/Cu composite particles were made into Li-half cells to measure electrochemical performance. The discharge specific capacity of Si/Cu3Si/Cu composite is up to 997 mAhg−1 at current density of 8.4 Ag−1 (2.0 C), which is over 100% higher than Si. Furthermore, the discharge specific capacity of Si/Cu3Si/Cu composite exhibits 1126 mAhg−1 after 100 cycles under current density of 0.5 C, exceeding that of Si by 216%.Owing to the better conductivity from copper, and interface alloy transitive structure enhancing the combining strength, Si/Cu3Si/Cu composite particles exhibit the excellent electrochemical performance.