Journal of Power Sources ( IF 9.2 ) Pub Date : 2018-02-22 , DOI: 10.1016/j.jpowsour.2018.02.038 Jennifer Ludwig , Tom Nilges
This review summarizes the development, investigation, and optimization of polymorphic lithium cobalt phosphate LiCoPO4. One of the three polymorphs known to date, olivine-type or Pnma-LiCoPO4, shows intriguing electrochemical properties as a high-voltage cathode material, which are of interest for next-generation lithium-ion batteries with higher energy density. Hence, scientists have developed optimization strategies to improve its performance for commercial applications. Herein, a number of procedures for the synthesis of Pnma-LiCoPO4 is presented, including thermodynamic as well as kinetically controlled approaches. The continuous improvement of its electrochemical performance is illustrated, which was realized by the development of solvothermal techniques that allow a precise particle size and morphology control. In the course of these investigations, two new polymorphs, Pna21-LiCoPO4 and Cmcm-LiCoPO4, have been discovered which show different physical and structural properties compared to Pnma-LiCoPO4. Despite their significantly poorer electrochemical performance, these polymorphs allow interesting insights into the variable structure chemistry of transition-metal phosphates, which canalizes in intriguing magnetic and thermal properties. The similarities and differences in the chemical and physical properties of Pnma-LiCoPO4, Pna21-LiCoPO4, and Cmcm-LiCoPO4 are discussed.
中文翻译:
磷酸锂钴化学的最新进展与发展-合成,多态性和性质
这篇综述总结了多晶型磷酸钴锂LiCoPO 4的开发,研究和优化。迄今为止已知的三种多晶型物之一,橄榄石型或Pnma -LiCoPO 4,显示出作为高压阴极材料的引人入胜的电化学特性,这对于具有更高能量密度的下一代锂离子电池很重要。因此,科学家们开发了优化策略来提高其在商业应用中的性能。本文中,有许多合成Pnma -LiCoPO 4的程序介绍了包括热力学以及动力学控制方法在内的方法。说明了其电化学性能的不断提高,这是通过溶剂热技术的发展实现的,该技术允许精确的粒径和形态控制。在这些研究中,两个新的多晶型物的过程中,PNA 2 1 -LiCoPO 4和CMCM -LiCoPO 4,已发现相比于显示不同的物理和结构特性的晶Pnma -LiCoPO 4。尽管它们的电化学性能明显较差,但这些多晶型物仍使人们对过渡金属磷酸盐的可变结构化学有有趣的见解,从而使磁性和热学性质引人入胜。在的化学和物理特性的相似性和差异晶Pnma -LiCoPO 4,PNA 2 1 -LiCoPO 4,和CMCM -LiCoPO 4进行了讨论。