Potential positive electrodes for high-voltage/high-power magnesium-ion batteries

采用镁金属负极的镁离子电池由于其二价离子的运动特性和低氧化还原电位，有望将高能量密度和高电动势结合起来。然而，迄今为止已有报道称，MIBs的电池电压不够高（~ 1）。5 V)，远低于锂离子电池（LIBs）(4？5 V)。在这项工作中，我们研究了Mg？有限公司?O和Mg？倪?O络合物氧化物作为MIBs的正极，由这些正极和一个Mg负极组成，在乙腈中以Mg(ClO4) 2盐作为电解质。这些mib可以表现出相对较高的开路电压，OCV。然而，由于乙腈电解质和金属Mg的结合会在Mg电极表面产生钝化，我们也对这些材料进行了完善的锂离子电池系统的检查，并确认充电后的电池可以显示出很高的OCV。为了获得如此高的电池电压，利用宿主复合物氧化物中电荷后的不稳定离子将是重要的。

Magnesium-ion batteries(MIBs) with a Mg-metal negative electrode are expected to combine high energy density and high electromotive force, owing to the divalent ion careers and its low redox potential. However, it has been reported to date that the cell voltage of MIBs is not high enough(~ 1. 5 V), being far below that of lithium-ion batteries(LIBs)(4? 5 V). In this work, we have investigated the potentiality of Mg? Co? O and Mg? Ni? O complex oxides as the positive electrode for MIBs, which are composed of these positive electrodes and a Mg negative electrode in acetonitrile with Mg(ClO4) 2 salt as an electrolyte. These MIBs can exhibit a relatively high open circuit voltage, OCV. However, as the combination of the acetonitrile electrolyte and metal Mg can yield the passivation on the surface of the Mg electrode, we have also checked these materials for a well-established Li ion battery system, and confirmed that the charged battery can show high OCV. In order to attain such a high cell voltage, it would be significant to exploit the unstabilized ionafter charge in the host complex oxide.