Demonstrating a Metal-Metal Battery System in Aprotic Electrolyte with Silver and Lithium

Metals are attractive materials for energy storage as they can undergo oxidation to accommodate charge transfer. However, traditional metal-metal batteries such as Cu−Zn have low voltage because of the use of an aqueous electrolyte. Here, we propose a metal-metal battery system with higher voltage in aprotic electrolyte with Ag/AgCl and Li/Li⁺ reactions on the cathode and anode, respectively. The Ag−Li cell gives a voltage of about 2.8 V and a capacity of close to 200 mAh g⁻¹. X-ray diffraction confirms the formation of AgCl during charging. The reduction of AgCl is faster than oxidation of Ag, so the battery has better discharge rate performance than charge. We also find that the solubility of the charge product (AgCl) in the electrolyte influences the cycle stability of the battery.