Centre for Clean Energy Technology, School of Mathematical and Physical Sciences, Faculty of Science , University of Technology Sydney , Broadway, Sydney , NSW 2007 , Australia.
College of Chemistry and Chemical Engineering , Yangzhou University , 180 Si-Wang-Ting Road , Yangzhou 225002 , China.
ACS Appl Mater Interfaces. 2018 Oct 3;10(39):33260-33268. doi: 10.1021/acsami.8b11471. Epub 2018 Sep 18.
Lithium-rich oxides have been regarded as one of the most competitive cathode materials for next-generation lithium-ion batteries due to their high theoretical specific capacity and high discharge voltage. However, they are still far from being commercialized due to low rate capability and poor cycling stability. In this study, we propose a heterostructured LiAlF coating strategy to overcome those obstacles. The as-developed lithium-rich cathode material shows outstanding performance including a high reversible capacity (246 mA h g at 0.1C), excellent rate capability (133 mA h g at 5C), and ultralong cycling stability (3000 cycles). Comparing with those of pristine and AlF-coated lithium-rich cathode materials, the enhanced performances can be attributed to the introduction of the lithium-ion-conductive nanolayer and the generation of nonbonding O species in the active material lattice, which enable rapid and effective lithium ion transport and diffusion. Our work provides a new strategy to develop high-performance lithium-rich cathode materials for high-energy-density lithium-ion batteries.
富锂氧化物因其高理论比容量和高放电电压而被认为是下一代锂离子电池中最具竞争力的正极材料之一。然而，由于其倍率性能差和循环稳定性差，它们仍远未实现商业化。在这项研究中，我们提出了一种异质结构的 LiAlF 涂层策略来克服这些障碍。所开发的富锂正极材料表现出出色的性能，包括高可逆容量（在 0.1C 时为 246 mA h g-1）、优异的倍率性能（在 5C 时为 133 mA h g-1）和超长的循环稳定性（3000 次循环）。与原始和 AlF 涂层的富锂正极材料相比，这些性能的提高可归因于锂离子导电纳米层的引入和活性材料晶格中非键合 O 物种的产生，这使得锂离子能够快速有效地传输和扩散。我们的工作为开发用于高能量密度锂离子电池的高性能富锂正极材料提供了一种新策略。
