Effective Chemical Prelithiation Strategy for Building a Silicon/Sulfur Li-Ion Battery

Prelithiation has important applications to convert a nonlithiated cathode or anode materials into a controllably lithiated state required for developing advanced Li-ion batteries. However, most of the prelithiation reagents developed so far are highly reactive and sensitive to oxygen and moisture and therefore difficult for practical battery application. In this work, we developed a facile prelithiation strategy using lithium naphthalenide to fully prelithiate sulfur–poly­(acrylonitrile) (S-PAN) composite into a Li2S-PAN cathode and to partially prelithiate nanosilicon into a Li x Si anode, which leads to a new version of silicon/sulfur Li-ion battery. This Li x Si/Li2S-PAN battery can demonstrate a high specific energy of 710 Wh kg–1, with a high initial Coulombic efficiency of 93.5% and a considerable cyclability. Also, this chemical prelithiation approach is mild, efficient, and widely applicable to a large range of Li-deficient electrodes, opening up new possibilities for development of low cost, environmentally benign, and high capacity Li-ion batteries.