Rational Structure Design of Fast-Charging NiSb Bimetal Nanosheet Anode for Lithium Ion Batteries

Abstract

Although bimetallic materials with various structures have been used as anodes for advanced lithium ion batteries, structural degradation, caused during electrochemical reactions, leads to a shorter cycle lifespan. Herein, we propose a rational structural design, carbon-wrapped porous bimetallic nickel-antimony nanosheets (NiSbNS@C), with the help of dual-functional organic acid acting as a reducing agent and a carbon coating source upon the synthetic process. The structural evolution of NiSbNS@C is further confirmed as the NiSb crystal is transformed into a Ni-rich phase on fast charging. A well-constructed NiSbNS@C electrode exhibits outstanding high rate performance and structure stability owing to the fast electrochemical kinetics of the porous NiSb nanostructure and uniform carbon decoration in both half and full cells. This approach opens up an avenue to make a desirable structure for bimetallic anode materials toward high rate and stable lithium ion batteries.