A SiOx/Sn/C hybrid anode for lithium-ion batteries with high volumetric capacity and long cyclability

Abstract Silicon sub-oxides (SiOx), one of the most promising anode materials for high energy lithium-ion batteries due to their high specific capacity and appropriate working potential, arouse extensive interest in both experimental and theoretical studies. However, their industrial application is hampered by low conductivity and large volume expansion. Focusing on the state-of-art of SiOx, an advanced SiOx/Sn/C hybrid is fabricated, in which, the 0D-Sn nanoparticles are in-situ reduced within the layer of SiOx, and the whole composite is modified by the carbon layer. The 2D-SiOx nanosheets and their interlayer spacing could alleviate the stress during the cycling process, further the inner intercalated Sn nanoparticles and outside carbon coating could enhance the electronic conductivity of the whole composite. Therefore, the as-prepared SiOx/Sn/C composite delivers good electrochemical performances such as a reversible capacity of 838.5 mA h g−1 at 0.1 A g−1 after 100 cycles and 654 mA h g−1 after 500 cycles at 1 A g−1. Additionally, the tap density of this hybird can reach to 0.74 g cm−3 due to the introduction of Sn. An impressive volumetric specific capacity of 1006 mAh cm−3 is maintained after 100 cycles. Herein, this ingenious material structural design is predicted to be an encouraging way to accelerate the industrial application of the SiOx-based anodes.