Hydrothermal synthesis and electrochemical properties of Fe1.19(PO4)(OH)0.57(H2O)0.43/C cathode material for Li-ion batteries

Recent rapid development of the portable electronic devices, growing interest in the electric vehicles and increasing integration the renewable energies required the development of cost-effective and high energy storage systems. Lithium-ion batteries are considered as system of the choice for variety of mobile and stationary applications. However, new electrode materials are demanded to increase the energy density of Li-ion batteries.
This presentation will report on the preparation and study of Fe1.19(PO4)(OH)0.57(H2O)0.43/C ((FPHH/C) composite as positive electrode material with high capacity and long cycle-life [1, 2]. FPHH/C (C= carbon black (CB) and carbon nanotubes (CNT)) composites were obtained by one-step the hydrothermal synthesis route. These cathode materials showed an excellent reversible capacity corresponding to 1.19 Li reaction. This is attributed to the stable and open structure of FPHH and also to the effect of carbon addition (CB and CNT) that improves the electronic percolation of the composite. The study of the reaction mechanism of FPHH/CNT during cycling by combining operando XRD and 57Fe Mossbauer spectroscopy (Figure 1) shows that the insertion mechanism is a monophasic reaction with 10% volume variations associated to the Fe3+/Fe2+ redox reaction [2].
References
1. C. Karegeya, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini. Electrochimica Acta 250 (2017) 49-58.
2. A. Mahmoud, C. Karegeya, M. T. Sougrati, J. Bodart, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. ACS Applied Materials and interfaces 10 (2018) 34202-34211.