Battery and Fuel Cell Technology

Mg is earth abundant and low-cost (ca. 24 times cheaper than Li), and as an anode material, Mg is safe to use without dendrite formation (vs. Li, Li-ion, or Na-ion batteries). Its high gravimetric capacity (2,333 Ah/kg) and high reduction potential (-2.37 V vs. SHE) allow the assembly of high-energy density batteries. However, despite rapid research progress, the lack of high performance Mg2+ conductive electrolytes still presents a primary technical hurdle for developing practical Mg batteries. The presentation will cover our research efforts in developing high performance Mg electrolytes for Mg rechargeable batteries. Specifically, we will present the synthesis and electrochemical performance of ternary Mg/MgCl2/AlCl3 (MMAC) electrolytes and other Mg electrolytes. For example, the MMAC electrolyte in DME exhibit 100% Coulombic efficiency, and 164 mV ovpotenail for Mg deposition, and 3.7 V vs. Mg anodic stability. Solution and interfacial chemistry of the presented Mg electrolytes will be discussed in detail. In addition, we will share our results on applying advanced Mg electrolytes in developing high energy density Mg rechargeable batteries. Our preliminary data showed that Mg/S batteries using the MMAC electrolyte could deliver 800 mAh/g capacity at a rate of 100 mAh/g.