Understanding the lithiation/delithiation process in SnP2O7 anode material for lithium-ion batteries. (20th October 2017)

• Record Type: Journal Article
• Authors: Bezza, Ilham; Trouillet, Vanessa; Fiedler, Andy; Bruns, Michael; Indris, Sylvio; Ehrenberg, Helmut; Saadoune, Ismael
• Is Part Of: Electrochimica acta. Volume 252(2017)
• Page Start: 446
• Page End: 452
• Publication Date: 2017-10-20
• Subjects: Li-ion batteries -- Anode material -- Carbon-coating XPS analysis -- SEI layer; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2017.09.023
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Anode materials based on silicon or tin, with distinctively higher theoretical specific capacities of 700 mAh/g compared to the commonly used graphite in Lithium-ion batteries exhibiting limited capacity of 370 mAh/g, are presently in the focus of intensive research studies as new anode materials. In the present work, coated and non-coated tin pyrophosphate materials were successively prepared and their electrochemical performance were compared. The use of carbon coating generally results in an improved cycling stability and a decrease in particles size. The X-ray diffraction patterns of the two samples are similar as indication of an amorphous character of the residual carbon. The scanning electron microscopy images of the both samples show a small particle size (nanometric) and the layers of the graphite are clearly observed. Raman spectroscopy was carried out to identify the D and G bands related to the graphite. X-ray photoelectron spectroscopy (XPS) was used to follow the Sn bonding/valence changes during discharge-charge process and also to identify the SEI layer which is formed at the last step of the discharge process.