Kalluri Sujith, Cha Hyungyeon, Kim Junhyeok, Lee Hyomyung, Jang Haeseong, Cho Jaephil
Department of Energy Engineering School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) 50 UNIST-gil Ulsan 44919 Republic of Korea.
Department of Electronics and Communication Engineering School of Engineering and Applied Sciences SRM University-AP Amaravati 522502 India.
Adv Sci (Weinh). 2020 Feb 11;7(7):1902844. doi: 10.1002/advs.201902844. eCollection 2020 Apr.
Nickel-rich materials, as a front-running cathode for lithium-ion batteries suffer from inherent degradation issues such as inter/intragranular cracks and phase transition under the high-current density condition. Although vigorous efforts have mitigated these current issues, the practical applications are not successfully achieved due to the material instability and complex synthesis process. Herein, a structurally stable, macrovoid-containing, nickel-rich material is developed using an affordable, scalable, and one-pot coprecipitation method without using surfactants/etching agents/complex-ion forming agents. The strategically developed macrovoid-induced cathode via a self-organization process exhibits excellent full-cell rate capability, cycle life at discharge rate of 5 C, and structural stability even at the industrial electrode conditions, owing to the fast Li-ion diffusion, the internal macrovoid acting as "buffer zones" for stress relief, and highly stable nanostructure around the void during cycling. This strategy for nickel-rich cathodes can be viable for industries in the preparation of high-performance lithium-ion cells.
富镍材料作为锂离子电池的前沿正极材料,存在诸如晶间/晶内裂纹以及在高电流密度条件下的相变等固有降解问题。尽管人们付出了巨大努力来缓解这些当前问题,但由于材料的不稳定性和复杂的合成过程,实际应用尚未成功实现。在此,通过一种经济实惠、可扩展的一锅共沉淀法,在不使用表面活性剂/蚀刻剂/络合离子形成剂的情况下,开发出一种结构稳定、含有大孔洞的富镍材料。通过自组织过程策略性开发的大孔洞诱导正极,由于锂离子快速扩散、内部大孔洞作为应力释放的“缓冲区”以及循环过程中孔洞周围高度稳定的纳米结构,在全电池倍率性能、5C放电率下的循环寿命以及即使在工业电极条件下的结构稳定性方面均表现出色。这种富镍正极的策略对于高性能锂离子电池的工业制备可能是可行的。