High lithium sulfide loading electrodes for practical Li/S cells with high specific energy

To date, Li₂S has drawn significant attention as a positive electrode active material for rechargeable lithium cells due to its high theoretical specific capacity and capability of pairing with a lithium-free anode which can obviate any safety concern of the lithium metal anode when using sulfur. In recent years, various approaches have been employed to develop Li/Li₂S rechargeable cells for commercialization that meet the performance goals for high energy/power applications. It is expected that high lithium sulfide-loading cells with long cycle life, an excellent capacity delivery and low electrolyte:sulfur weight ratio (E/S ratio) can be achieved. Here, we report a Li₂S electrode comprised of a novel Li₂S/KB@Cf nanocomposite which delivers an areal capacity of 7.56 mAh cm^-2 and good cycling stability with a mass loading of 11.29 mg cm^-2 and a robust 3-dimensional (3D) aluminum foam current collector with a high open area. The high conductivity and scalability of the active material, the availability of 3D current collection for the active material and the control of the electrolyte/sulfur ratio offer the potential of realization of practical Li/S cells.