Onion-Structured Si Anode Constructed with Coating by Li4Ti5O12 and Cyclized-Polyacrylonitrile for Lithium-Ion Batteries

Abstract

Low dimensional Si-based materials are very promising anode candidates for the next-generation lithium-ion batteries. However, to satisfy the ever-increasing demand in more powerful energy storage devices, electrodes based on Si materials should display high-power accompanied with low volume change upon operation. Thus far, there were no reports on the Si-based materials which satisfy the stated requirements. Hence, here, we report on modified onion-structured Si nanoparticles (SiNPs) co-coated with Li4Ti5O12 (LTO) and cyclized polyacrylonitrile (cPAN) to bring the synergistic effect enhancing the conductivity, tolerance to volume change and stable performance. Obtained results suggest that the nanoparticles were conformally coated with both materials simultaneously and the thicknesses of the films were in a range of a few nanometers. Electrochemical tests show that the modified SiNPs deliver a high initial capacity of 2443 mAh g−1 and stable capacity retention over 50 cycles with 95% Coulombic efficiency.

Biomass-Derived Porous Carbon from Agar as an Anode Material for Lithium-Ion Batteries

“…Furthermore, it is worth mentioning the high cost and negative environmental impact due to its synthesis from fossil carbon sources such as coal and petroleum coke [ 7 ]. Therefore, it is highly desirable to explore alternative negative electrode materials for Li-ions such as tin [ 8 , 9 ], transition metal oxides [ 10 , 11 , 12 , 13 ], silicon [ 14 , 15 ], and others. Although the alternative anodes can provide higher specific capacity, they suffer from substantial volume changes during insertion/extraction of Li-ions causing materials disintegration leading to huge irreversible capacity loss and poor cyclability.…”