Controlled synthesis of spherical hierarchical LiNi1-x-yCOxAlyO2 (0<x, y<0.2) via a novel cation exchange process as cathode materials for High-Performance Lithium Batteries

A series of spherical hierarchical LiNi1 (x) yCoxAlyO2 (0 <x, y <0.2) were successfully synthesized via a novel and simple cation exchange process. Specifically, spherical flowerlike Ni-1 (x) yCOxAly(OH)(2 + y) (0 < x, y < 0.2) were obtained from (Ni0.85Co0.15)(3)(NO3)(2)(OH)(4) via the cation exchange between Al ion and Ni/Co ions while maintaining its morphology. Then, after calcination, the hierarchical spherical LiNi1 (x) yCOxAlyO2 (0 < x, y < 0.2) could be easily obtained. Among these materials, the hierarchical spherical LiNi0.84Co0.14Al0.02O2 performs the discharge capacity of 190 mAh g (1) at 20 mAg (1) at the second cycle, while the material LiNi0.85Co0.15O2 obtained using the (Ni0.85Co0.15)(3)(NO3)(2)(OH)(4) without ion exchange performs a discharge capacity of 165 mAh g (1). Furthermore, the hierarchical spherical LiNi0.84Co0.14Al0.02O2 maintains the high capacity retention of 84.0% after 225 cycles at 200 mAg (1). This work exploits a new and facile way to synthesize high capacity Al-contained layered metal oxides cathode materials. (C) 2016 Elsevier Ltd. All rights reserved.