Cobalt-free Single Crystal Layered Cathode Materials for Lithium-Ion Batteries

锂离子电池(Lib)比传统技术具有更高的效率、更高的能量密度和更长的循环寿命，是一种很有前途的电化学储能和转换技术，特别是在电网储能和电动汽车方面。尽管在室温下具有稳定的循环寿命，但商用锂离子电池含有有毒的钴基阴极(LiCoO2)，在高截止电压和高温测试下的性能不够好。正极材料应用于大规模锂离子电池的主要要求是在不牺牲其电化学性能的情况下，含有价格较低、毒性较低的材料。此外，用于合成锂正极材料的传统共沉淀法会向环境排放大量有毒副产物。因此，设计一种低成本、低毒的正极材料，在高压和高温下都能提供高的稳定性和倍率性能是至关重要的。此外，传统的多晶正极材料在充放电过程中由于各向异性应力发生了严重的结构变化，影响了其长期稳定性，因此还应制作焦点来取代传统的多晶正极材料。因此，拟议的项目旨在以环境友好的方式开发环境友好的LIBS单晶层状正极材料。这些新型单晶正极材料非常适合高压应用，因为它们对电化学反应过程中的微裂纹和结构变化具有很强的抵抗力。滑铁卢大学陈忠伟博士的团队将与两家领先的工程零部件制造商Pro-Flange和Canada Solar合作，使用闭环、最少浪费的合成方法设计和制备结构稳定的单晶层状金属氧化物阴极材料，用于LiB应用。最终，该项目将帮助加拿大LIB制造商以较低的成本和较小的环境影响，为加拿大及其他地区的电动汽车和能源电网存储应用生产大规模电池。此外，该项目还将提供丰富培训经验的机会。

Lithium-ion batteries (LIB) are promising electrochemical storage (EES) techniques for energy storage and conversion especially for energy grid storage and electric vehicles as they offer higher efficiency, higher energy density and longer cycle life than conventional technologies. Despite delivering stable cycle life at room temperature, commercial LIBs contain toxic cobalt-based cathodes (LiCoO2) and its performance at high cut-off voltages and high-temperature testing is not adequate. The main requirement for cathode materials to be applied in large scale LIBs is that should contain less expensive and low toxic materials without sacrificing its electrochemical performance. In addition, conventional co-precipitation methods used for LIB cathode materials synthesis discharge toxic by-products to the environment in very large quantities. Therefore, it is essential to design a low cost and less toxic cathode materials that can deliver high stability and rate performance at both high voltages and temperature operation. Besides, the focuses should also be made to replace the conventional polycrystalline cathode materials, which undergo severe structural alterations during the charge-discharge process due to the anisotropic stress, affecting its long-term stability. Hence, the proposed project targets the development of environmentally benign cobalt-free single crystal layered cathode materials for LIBs in an eco-friendly way. These novel single crystal cathode materials are suitable for high voltage applications as they are very robust against microcracks and structural changes during the electrochemical reactions. Dr. Zhongwei Chen's group at the University of Waterloo will work with two leading manufacturers of engineered parts, Pro-Flange, and Canadian Solar to design and prepare structurally stable, single crystal, layered metal oxide cathode materials for LIB applications using a closed-loop, minimal waste synthesis method. Ultimately, the project will help enable Canadian LIB manufacturers to produce large scale batteries for the applications of electric vehicles and energy grid storage in Canada and beyond, at a lower cost and with less environmental impact. Moreover, this project will offer opportunities for enriched training experiences.