Recent advances of magnesium hydride as an energy storage material

Energy storage is the key for large-scale application of renewable energy, however, massive efficient energy storage is very challenging. Magnesium hydride (MgH2) offers a wide range of potential applications as an energy carrier due to its advantages of low cost, abundant supplies, and high energy storage capacity. However, the practical application of MgH2 for energy storage is still impeded by its sluggish kinetics, poor cycling stability, etc. Herein, we provide an overview of recent advances of MgH2 for enhancing the hydrogen storage, lithium-ion storage, and heat storage performances. For hydrogen storage, a particular emphasis was put on altering the kinetics and thermodynamics of MgH2 via catalyzing, alloying, nanosizing, and compositing. Modifications to MgH2 as a battery anode material mainly focus on the effect of additives, electrolytes, and structure configurations. Prototype heat storage apparatus was proposed based on MgH2 and coupled with other materials or systems to improve the heat storage and economic efficiency. Besides, prospects of MgH2 in these fields are discussed. This review would stimulate more insightful and pioneering research for the design and preparation of MgH2 with excellent energy storage performances.