1137
Advanced Electrolyte for Rechargeable Magnesium Batteries  

Thursday, 23 June 2016
Riverside Center (Hyatt Regency)
J. H. Ha, B. W. Cho (Korea Institute of Science and Technology), L. F. Nazar (University of Waterloo), and S. H. OH (Korea Institute of Science and Technology)
Recently, rechargeable magnesium batteries gains more and more attention as a commercially-viable future energy storage system for mid-/large-scale applications such as ESS and electric vehicles (EV).[1-4] Magnesium is attractive as an anode material, since it is not only naturally abundant, but delivers a high gravimetric and volumetric capacity of 2,205 mAh/g and 3,833 mAh/cm3 at relatively low reduction potential of -2.372 V vs. standard hydrogen electrode. Therefore, batteries based on magnesium metal negative electrode can be potentially manufactured at very low cost and possess a market competitiveness in their energy density. However, the most intriguing problems of these systems are slow development of electrolyte systems having a reversible Mg plating/stripping character on the anode without a dendrite formation and at the same time exhibiting a wide electrochemical window, which would hire a cathode material having a high electrode potential for the high energy density of the system. It is well-known that the conventional Grignard solution (RMgX, R = alkyl or aryl, X = Cl, Br) which has a good reversibility on Mg plating/stripping reaction, functions as strong nucleophile and its anodic stability is poor so that it cannot be applied to common cathode materials. In this work, we will present a new electrolyte system which can be prepared by a simple process and can be directly applied to magnesium electrode with a high coulombic efficiency more than 99.9 % and stability up to 4.0 V vs. magnesium electrode. We will characterize this electrolyte system through many analysis tools including NMR, single-crystal XRD and other spectroscopic methods. We will also show that full cells employing Mo6S8 Chevrel phase cathode and this new electrolyte can be run for hundreds of cycles without a noticeable capacity fading.

References

[1] D. Aurbach et al., Nature, 407(2000) 724

[2] D. Aurbach et al., Energy Environ. Sci., 6 (2013) 2265.

[3] R. Mohtadi et al., Beilstein J. Nanotechnol., 5(2014) 1291.

[4] J. Muldoon et al., Energy Environ. Sci., 5 (2012) 5941.