Bi Dots Confined by Functional Carbon as High‐Performance Anode for Lithium Ion Batteries

Abstract

Fabrication of Bi/C composites is a common approach to alleviate the severe volume expansion of Bi alloy‐based anodes with a high theoretical capacity of 3800 mAh cm−3 for lithium ion batteries (LIBs). However, the complicated and tedious synthetic routes restrict its large‐scale preparation and practical applications. Herein, a spongiform porous Bi/C composite (marked as Bi@PC) through the carbothermal reduction (CTR) method is constructed. Bi nanodots are in situ confined in a porous carbon substrate activated by the gases produced from the decomposition of the sodium phytate precursor, indicating the feasibility and simplicity of this route. In charge/discharge processes, Bi nanodots embedded in carbon matrix are effective enough to accommodate the strain change and shorten the migration distance. In addition, the porous carbon forms an efficient conductive network for electron shutting. When utilized for lithium storage, a superb capacity of 520 mAh g−1 at 0.2 A g−1 after 100 cycles and a satisfying long cyclic stability of 380 mAh g−1 at 0.5 A g−1 after 500 cycles are achieved. The excellent Li‐storage performance and this handy preparation method jointly make this Bi/C composite a potential anode for LIBs, and could inspire the preparation of other alloy‐type anodes.

Prelithiation/Presodiation Techniques for Advanced Electrochemical Energy Storage Systems: Concepts, Applications, and Perspectives

“…Especially, Si electrode suffers from the low initial coulombic efficiency (ICE) (typically 50-80%) triggered by the formation of SEI layer. [50,51] In addition, the dramatic volume fluctuation could consume a large amount of lithium/sodium due to the recurrent growth/destruction of the SEI layer. Importantly, the losing active lithium/sodium contents of anode could be compensated via prelithiation/presodiation technologies, which further guarantees an enhanced energy density.…”

Regulating the Solvation Sheath of Li Ions by Using Hydrogen Bonds for Highly Stable Lithium–Metal Anodes

“…The rising of energy demand is calling for alternatives of traditional lithium‐ion batteries (LIBs) [1–10] . In this regard, the lithium‐metal batteries (LMBs) provide a new possibility for high energy density systems [8, 11–18] by using Li metal as anodes, due to its ultrahigh theoretical capacity (3860 mAh g −1 ) and low electrochemical potential (−3.04 V vs. the standard hydrogen electrode).…”

Bi‐Based Electrode Materials for Alkali Metal‐Ion Batteries

“…Due to the poor electrical conductivity of bismuth and the strong volume expansion during the alloying process, coating Bi with carbon matrix is an effective method to improve the electrochemical performance. Hence, our group [79] constructed a spongy porous Bi/C composite by one-step carbothermal reduction (CTR) method. On one hand, the porous carbon [42] Copyright 2018, American Chemical Society.…”

“…d) Schematic diagram of spongiform porous Bi/C composite constructed by one‐step carbothermal reduction method; (d) Reproduced with permission. [ 79 ] Copyright 2020, Wiley‐VCH. e) Schematic presentation of the Egg‐Carton‐Inspired design and the synthesis procedure of Bi/C composite sheets; f) Cross‐sectional SEM images of Bi/C‐1000 electrode: fresh electrode, fully lithiation and after delithiation; (e,f) Reproduced with permission.…”