Synthesis of lithium rich layered oxides with controllable structures through a MnO2 template strategy as advanced cathode materials for lithium ion batteries

Abstract

The electrochemical performance of lithium ion batteries depend largely on the structural properties of electrode materials. In this work, we propose an approach to synthesize lithium-rich layered oxides (LLOs) materials using a manganese dioxide (MnO2) template strategy, which could control the structure and particle size of final products via choosing different MnO2 templates. Through precisely optimizing, we successfully prepare cross-linked nanorods (CLNs) and agglomerate microrods (AMs) Li1.2Ni0.15Co0.1Mn0.55O2 cathode materials by using carbon-decorated MnO2 nanowires and MnO2 nanorods as templates, respectively. The lithium ion battery based on the CLNs exhibits excellent performance, delivering a high capacity of 286.2 mAh g−1 at 0.1 C and 237.5 mAh g−1 at 1 C. In addition, the device remains 98% and 89% of its initial capacity after 50 cycles at 0.1 C and 100 cycles at 1 C, respectively. The remarkable electrochemical performance can be mainly attributed to the cross-linked nanorods structure which can provide relatively shorter lithium ion diffusion length, larger reaction surface and more internal cavity. This universal structure engineering strategy may shed light on new material structures for high performance lithium-rich layered oxide cathode materials.