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LiCoO 2 (LCO) has been functionally modified by mixed lithium ion and electron conducting LiAlPO 3.93 F 1.07 (LAPF) for the first time. Due to the unique coating layer with accepted Li-ion diffusion rate and electronic conductivity, the LAPF-coated LCO exhibits outstanding rate capability and cycle stability in the voltage range of 2.75–4.55 V. This material delivered a specific capacity of 206 mAh·g − 1 up to 0.5C rate and the capacity retention was 91.7% after 50 cycles, which is a remarkable improvement comparing with uncoated LCO (34.8%). It also exhibited superior rate capability with a discharge capacity of 161.4 mAh·g − 1 at 4C. The functionalized LAPF coating technique is an efficient approach to improve the electrochemical performance of LCO and can also be referred for other layered oxide cathode materials. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotube (CNT) wired LiCo0.5Mn0.5PO4 nanocomposites were readily prepared using a facile one-pot hydrothermal approach. The prepared LiCo0.5Mn0.5PO4-CNT is composed of uniform nanoparticles of LiCo0.5Mn0.5PO4 intimately interconnected by CNT networks. The electrochemical test results show that the CNT networks play a critical role in maintaining electrical conduction and in ensuring electrode stability of LiCo0.5Mn0.5PO4-CNT upon cycling, thus leading to much enhanced electrochemical properties compared with neat LiCo0.5Mn0.5PO4. It is found that the LiCo0.5Mn0.5PO4-CNT composite exhibits a high capacity up to 151mAhg−1 and an energy density of 620mWhg−1, and maintain 92% of the initial capacity after 30 charge/discharge cycles, thereby indicating its potential for energy storage and conversion application. [Copyright &y& Elsevier]