Electroless Sn-Cu Alloy Electrodes for Li-Ion Batteries

Cu was electrolessly deposited onto an activated carbon cloth. To prepare the Sn-Cu alloy material, the Cu coated cloth was immersed in a tin bath of composition 28 g/L of stannous sulfate (SnSO₄), 80 g/L of sodium hypophosphite (NaH₂PO₂), and 80 g/L of thiourea (Tu) for 30 seconds or more. A partial dispalcement of Cu and subsequent formation of Sn-Cu alloy resulted from the dispalcement step. The Sn-Cu alloy sample was used in a Li cell in which polytetrafluoroethylene (PTFE) membrane was sandwiched between the cathode and a lithium foil. The Sn-Cu alloy electrode cell was charged and discharged by applying a constant current at different current rates including 0.25 mA, 0.5 mA, 1 mA, and 2 mA, respectively. The results of the cell performance evaluation as a battery will be presented and the overall concept of the electrode material fabrication discussed.