Lithiation of electrodeposited silicon films

Lithium-ion batteries with improved performance are increasingly in demand in various fields. Silicon-based materials are one of the most actively studied materials, because they allow increasing the discharge capacity of the anode. In this work, we continue studying the behavior of the thin-film silicon anodes inside the anode half-cell of a lithium-ion battery in the conditions of limited charge capacity to 1000 and 4000 mA·h/g. Samples of silicon films, electrodeposited from the molten KI-KF-KCl-K2SiF6 electrolyte with the temperature of 700°C on glassy carbon in the potentiostatic mode, were used as the objects of the research. It was noted that limiting the charge capacity makes it possible to increase the number of cycles maintaining a relatively high discharge capacity and to increase the operational life of the electrodeposited silicon films. Applying the C/10 cycling current and limiting the charge capacity to 4000 mA·h/g, the discharge capacity of the samples was 3850–3930 mA·h/g, and using the 2C cycling current it was up to 3000 mA·h/g.