화학공학소재연구정보센터
Electrochimica Acta, Vol.256, 316-324, 2017
An ingenious design of lamellar Li1.2Mn0.54Ni0.13Co0.13O2 hollow nanosphere cathode for advanced lithium-ion batteries
Although very appealing in developing hollow structured lithium-rich layered transition-metal oxides as cathodes for lithium-ion batteries (LIBs), a great challenge lies in controlling the growth of transition metal elements with desired molar ratios while maintaining intact hollow structures during synthesis. Herein, we propose a scalable strategy to successfully synthesize novel lamellar Li1.2Mn0.54Ni0.13Co0.13O2 hollow (L-LMOH) nanosphere cathode for advanced lithium-ion batteries (LIBs). It is proved that the employment of sulfonated polystyrene (SPS) gel nanospheres as the template plays a key role in the formation of flower-like SPS@ Ni-Co-Mn-precursor nanospheres with desired molar ratios, and a subsequently delicate control in the heating rate leads to the intact L-LMOH nanospheres. It is demonstrated that the use of L-LMOH nanosphere cathode not only delivers outstanding reversible discharge capacities of 281.7 mAh g(-1) at a current density of 20 mA g(-1) and 136.6 mAh g(-1) at 2000 mA g(-1), but also possess superior cycling stability with a capacity reservation of 80% at 2000 mA g(-1) after 200 continuous cycles. It is well analyzed that the ingenious design of both unique lamella and hollow architectures synergistically benefits the significantly enhanced rate capability and cycling stability. (C) 2017 Published by Elsevier Ltd.