Li Pre-doping of Amorphous Silicon Electrode in Li-Naphthalene Complex Solutions

To compensate a large initial irreversible capacity (Qirr) of silicon electrode, a novel Li pre-doping technique using Li-naphthalene complex/tetrahydrofuran solutions was developed. Li was successfully doped to amorphous silicon nano-flake particles, and the doping level of Li was easily controlled by adjusting naphthalene concentration. A large Qirr of the pristine electrode (1200 mAh g−1) was almost completely compensated after pre-doped in 0.1 mol dm−3 Li-naphthalene solution for 1 h. In addition, no harmful effects of pre-doping on cycleability were observed.