Issues and Challenges of Ni-Rich Layered Lithium Transitional Metal Oxide for High Energy Lithium-Ion

High energy density lithium ion batteries are extremely demanded for portable electronic devices and electrical vehicles. Since the energy density of the batteries rely heavily on the cathode material used, a major effect has been in progress to develop alternative cathode materials with a higher degree of lithium utilization and specific energy density. In particular, layered Ni-rich lithium transitional metal oxides can deliver higher capacity with lower cost compared to the conventional LiCoO₂, regarding as the most promising candidates. However, these Ni-rich compounds still have several challenges associated with their intrinsic properties, such as cycle life, thermal stability, and safety issues. There have been numerous breakthroughs to deal with these problems by extensive scientific efforts. In this review, the performance enhancement of Ni-rich cathode materials through structure tuning or interface engineering will be discussed. The underneath mechanisms and remaining challenges will also be discussed for further development to bring these cathode materials from laboratory interest into large scale application.