title: Coordination chemistry in magnesium battery electrolytes: how ligands affect their performance.
abstract: Magnesium battery is potentially a safe, cost-effective, and high energy density technology for large scale energy storage. However, the development of magnesium battery has been hindered by the limited performance and the lack of fundamental understandings of electrolytes. Here, we present a study in understanding coordination chemistry of Mg(BH₄)₂ in ethereal solvents. The O donor denticity, i.e. ligand strength of the ethereal solvents which act as ligands to form solvated Mg complexes, plays a significant role in enhancing coulombic efficiency of the corresponding solvated Mg complex electrolytes. A new electrolyte is developed based on Mg(BH₄)₂, diglyme and LiBH₄. The preliminary electrochemical test results show that the new electrolyte demonstrates a close to 100% coulombic efficiency, no dendrite formation, and stable cycling performance for Mg plating/stripping and Mg insertion/de-insertion in a model cathode material Mo₆S₈ Chevrel phase.
authors.affiliation: Pacific Northwest National Laboratory, Richland WA, 99352, USA.
authors.forename: Yuyan
authors.initials: Y
authors.lastname: Shao
authors.forename: Tianbiao
authors.initials: T
authors.lastname: Liu
authors.forename: Guosheng
authors.initials: G
authors.lastname: Li
authors.forename: Meng
authors.initials: M
authors.lastname: Gu
authors.forename: Zimin
authors.initials: Z
authors.lastname: Nie
authors.forename: Mark
authors.initials: M
authors.lastname: Engelhard
authors.forename: Jie
authors.initials: J
authors.lastname: Xiao
authors.forename: Dongping
authors.initials: D
authors.lastname: Lv
authors.forename: Chongmin
authors.initials: C
authors.lastname: Wang
authors.forename: Ji-Guang
authors.initials: JG
authors.lastname: Zhang
authors.forename: Jun
authors.initials: J
authors.lastname: Liu