Lithium Batteries with Nearly Maximum Metal Storage.

The drive for significant advancement in battery capacity and energy density inspired a revisit to the use of Li metal anodes. We report the use of a seamless graphene-carbon nanotube (GCNT) electrode to reversibly store Li metal with complete dendrite formation suppression. The GCNT-Li capacity of 3351 mAh g approaches that of bare Li metal (3861 mAh g), indicating the low contributing mass of GCNT, while yielding a practical areal capacity up to 4 mAh cm and cycle stability. A full battery based on GCNT-Li/sulfurized carbon (SC) is demonstrated with high energy density (752 Wh kg total electrodes, where total electrodes = GCNT-Li + SC + binder), high areal capacity (2 mAh cm), and cyclability (80% retention at >500 cycles) and is free of Li polysulfides and dendrites that would cause severe capacity fade.