Durable lithium storage of Si anode enabled by semi-embedded integration of SnO2 onto surface

Herein, a high-performance Si-based anode (Si@SnO 2 @C) has been obtained by semi-embedded integration of ultrafine SnO 2 nanoparticles onto the surface of cost-effective irregular Si particles and further coated with an ultrathin carbon through a simple route. The results verify that the in-situ conversion of SnO 2 into Li x Sn during lithiation process contributes to superb lithium storage performance of the Si particles, such as high capacity (1071.2 mAh g −1 after 500 cycles at 400 mA g −1 ) and long lifespan (1000 cycles). Finally, this study might be able to offer a viable strategy for facilely preparing Si-based anodes with advanced performance for lithium-ion batteries. The lithium storage performance of irregular Si particles can be significantly improved through the well-designed in-situ conversion of SnO 2 into Li x Sn, demonstrating high capacity and long cycle life. • The performance of Si anode was significantly improved after integration SnO 2 onto surface. • The in-situ conversion of SnO 2 into Li x Sn improved kinetics and durability of Si during cycle. • The findings offered new insights into enhancing performance of Si-based anodes. • The resulting Si@SnO 2 @C had high capacity (1071.2 mAh g −1 ) and durable cycle performance (1000 cycles).