A High-Energy Density Li metal Dual-Ion Battery with Lithium Nitrate-Modified Carbonate-Based Electrolyte.

The Lithium (Li) metal is a favorable anode for most energy storage systems owing to its higher theoretical specific capacity. However, non-uniform Li nucleation/growth results in large-sized and irregularly dendrites generated of the Li anode, which causes rapid capacity fade and serious safety hazard, hindering its widespread practical applications. In this paper, with aid of Lithium nitrate (LiNO3) additive in the carbonate-based electrolyte, the Li anode shows a low hysteresis for in excess of 1000 h at a current density of 0.5 mA cm-2. At the same time, the Li-graphite dual-ion battery exhibits an outstanding cycling stability at 5 C, with capacity retention of 81% after 1000 cycles. After calculation, the Li-graphite dual-ion battery shows a competitive specific energy density of 243 Wh kg-1 at a power density of 234 W kg-1. Moreover, Linear Sweep Voltammogram test was performed to analyze the Li nucleation/growth mechanism and explain the effect of the LiNO3 additive for the first time. The superior electrochemical properties of the Li-graphite dual-ion battery is ascribed to the generation of a smooth Li composed of Li nanoparticles and formation of a steady solid electrolyte interface film.interface film.