title: High areal capacity hybrid magnesium-lithium-ion battery with 99.9% Coulombic efficiency for large-scale energy storage.
abstract: Hybrid magnesium-lithium-ion batteries (MLIBs) featuring dendrite-free deposition of Mg anode and Li-intercalation cathode are safe alternatives to Li-ion batteries for large-scale energy storage. Here we report for the first time the excellent stability of a high areal capacity MLIB cell and dendrite-free deposition behavior of Mg under high current density (2 mA cm(-2)). The hybrid cell showed no capacity loss for 100 cycles with Coulombic efficiency as high as 99.9%, whereas the control cell with a Li-metal anode only retained 30% of its original capacity with Coulombic efficiency well below 90%. The use of TiS2 as a cathode enabled the highest specific capacity and one of the best rate performances among reported MLIBs. Postmortem analysis of the cycled cells revealed dendrite-free Mg deposition on a Mg anode surface, while mossy Li dendrites were observed covering the Li surface and penetrated into separators in the Li cell. The energy density of a MLIB could be further improved by developing electrolytes with higher salt concentration and wider electrochemical window, leading to new opportunities for its application in large-scale energy storage.
authors: †Department of Electrical and Computer Engineering and Materials Science and Engineering Program, University of Houston, Houston, Texas 77204, United States.
authors: Hyun Deog
authors: HD
authors: Yoo
authors: †Department of Electrical and Computer Engineering and Materials Science and Engineering Program, University of Houston, Houston, Texas 77204, United States.
authors: Yanliang
authors: Y
authors: Liang
authors: †Department of Electrical and Computer Engineering and Materials Science and Engineering Program, University of Houston, Houston, Texas 77204, United States.
authors: Yifei
authors: Y
authors: Li
authors: †Department of Electrical and Computer Engineering and Materials Science and Engineering Program, University of Houston, Houston, Texas 77204, United States.|‡Texas Center for Superconductivity, University of Houston, Houston, Texas 77204, United States.
authors: Yan
authors: Y
authors: Yao
keywords: Coulombic efficiency; dendrite-free magnesium deposition; energy storage; hybrid magnesium−lithium-ion batteries (MLIBs)