Mechanically and structurally stable Sb2Se3/carbon nanocomposite as anode for the lithium-ion batteries

摘要

Metal chalcogenides undergoing alloying and conversion mechanism can give high capacity as anode for lithium-ion batteries. However, large volume change and phase segregation lead to poor cycle performance. In this study, we focus on Sb2Se3 and develop methods to enhance its long-term stability and reversibility. In particular, we find that carbon encapsulation reduces volume change during lithiation/delithiation and facilitates the recombination process of Sb and Se even after long cycling. With an addition of 20 wt% acetylene black, the Sb2Se3/C nanocomposite material exhibits an excellent cycle performance with a charge capacity of 545 mAh g(-1) at 250 mA g(-1) after 1000 cycles, corresponding to a capacity retention of 99.3%. We also demonstrate a full cell with LiFePO4 cathode and Sb2Se3/C anode that is capable of delivering a stable capacity of 340 mAh g(-1) at 1 A g(-1) (about 3 C rate) after 300 cycles. (c) 2021 Elsevier B.V. All rights reserved.