“…Meanwhile, lithium-ion batteries, as the power source, have been developed quickly in recent years [1,2,3,4,5,6,7,8]. It is generally known that there are four major classes of mature cathode materials, namely LiCoO 2 [9,10], LiFePO 4 [11,12], LiNi 1−x−y Co x M y O 2 (M = Mn, Al) [13,14], and LiMn 2 O 4 [15,16], for batteries. Among these materials, LiMn 2 O 4 shows many virtues such as mature production technology, cheap production costs, non-pollution characteristics, and so forth [17,18,19,20].…”