Yolk structure of porous C/SiO2/C composites as anode for lithium-ion batteries with quickly activated SiO2.

A yolk structure of C/SiO 2 /C and a hollow structure of C/SiO 2 composites with porous feature are synthesized by one-step method and two steps method, respectively. When evaluate as an anode material for lithium-ion batteries (LIBs), the C/SiO 2 /C and C/SiO 2 deliver an impressive cycle performance and exhibit an excellent rate capacity. More importantly, attributing to the one-step synthesis method of C/SiO 2 /C, it possesses interconnected micropore and higher special surface area, which provide a more efficient ionic transportation path and facilitate the diffusion of Li + between the electrolyte and C/SiO 2 /C, thus the activation time of SiO 2 can be effectively shorten. The capacity achieves the steady value of 1135 mAh g −1 (based on the weight of SiO 2 in the electrode material) only by 60 cycles at 50 mA g −1 which is much faster than that of C/SiO 2 and delivers a high-rate capacity of 390 mAh g −1  at 1000 mA g −1 . Considering the good lithium storage abilities and fast-activated features, the C/SiO 2 /C composites hold promise in applications in practical LIBs. [ABSTRACT FROM AUTHOR]