Qingdao Energy Storage Industry Technology Research Institute, based on the previous work on magnesium secondary batteries, obtained a new type of organic magnesium borate-based electrolyte through one-step in-situ synthesis, which effectively improved the cycle of magnesium/sulfur batteries Performance and rate performance are expected to push the low-cost and high-energy density magnesium/sulfur battery system into practical use. The relevant research results are published in Energy&EnvironmentScience.
This research uses tris(hexafluoroisopropyl) borate (THFPB), magnesium chloride (MgCl2) and magnesium powder as raw materials, in ethylene glycol dimethyl ether (DME) solvent, through a one-step in-situ reaction to obtain [B( HFP)4]-is an anion, [Mg4Cl6(DME)6]2+ is an organic magnesium borate-based electrolyte. The electrolyte system exhibits excellent magnesium ion conductivity: the electrochemical window is as high as 3.3V (vs.Mg), the ion conductivity is as high as 5.58mS/cm, the electrodeposition overpotential is only 0.11V, and the coulombic efficiency of deposited dissolved magnesium exceeds 98. %. In addition, the electrolyte has excellent non-nucleophilic properties and is well compatible with sulfur cathodes. The magnesium/sulfur battery assembled with this electrolyte still has a specific discharge capacity of 1000mAh/g after 100 cycles of charge and discharge, and can still work normally under the condition of high current charge and discharge of 500mA/g. This is the current report The most excellent performance data in the research of magnesium-sulfur battery.
Simple synthesis method and excellent magnesium-sulfur battery performance are the biggest advantages of this organic magnesium borate-based electrolyte. This research result is expected to accelerate the practical process of magnesium/sulfur battery system