Superior Hybrid Cathode Material Containing Lithium-Excess Layered Material and Graphene for Lithium-Ion Batteries
Superior Hybrid Cathode Material Containing Lithium-Excess Layered Material and Graphene for Lithium-Ion Batteries
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用于锂离子电池的含过量锂层状材料和石墨烯的优质混合正极材料
DOI：
10.1021/am301202a
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发表时间：
2012-09-01
影响因子：
9.5
通讯作者：
Guo, Yu-Guo
中科院分区：
文献类型：
--
作者：
Jiang, Ke-Cheng;Wu, Xing-Long;Guo, Yu-Guo
合成了石墨烯包覆的层状锂过量杂化材料（Li2MnO3中心点LiMO2，M = Mn，Ni，Co，以下简称LMNCO），并将其作为锂离子电池正极材料进行了研究。循环伏安法测量表明，在石墨烯导电框架的好处的反应过电位的显着降低。电化学阻抗谱结果表明，石墨烯可以大大降低电池电阻，尤其是电荷转移电阻。我们的研究表明，石墨烯导电框架可以有效地减轻原始LMNCO材料的极化，从而显著增强电池性能和循环稳定性。这种上级的电化学性能支持了通过将活性材料包裹在石墨烯纳米片中而进行的精细混合结构设计，用于高容量和高倍率的阴极材料。
Graphene-wrapped lithium-excess layered hybrid materials (Li2MnO3 center dot LiMO2, M = Mn, Ni, Co, hereafter abbreviated as LMNCO) have been synthesized and investigated as cathode materials for lithium-ion batteries. Cyclic voltammetry measurement shows a significant reduction of the reaction overpotential in benefit of the graphene conducting framework. The electrochemical impedance spectroscopy results reveal that the graphene can greatly reduce the cell resistance, especially the charge transfer resistance. Our investigation demonstrates that the graphene conducting framework can efficiently alleviate the polarization of pristine LMNCO material leading to an outstanding enhancement in cell performance and cycling stability. The superior electrochemical properties support the fine hybrid structure design by enwrapping active materials in graphene nanosheets for high-capacity and high-rate cathode materials.