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Title: A new family of cation-disordered Zn(Cu)–Si–P compounds as high-performance anodes for next-generation Li-ion batteries
The development of low-cost, high-performance anode materials for Li-ion batteries (LIBs) is imperative to meet the ever-increasing demands for advanced power sources. Here we report our findings on the design, synthesis, and characterization of a new cation-disordered ZnSiP 2 anode. When tested in LIBs, the disordered phase of ZnSiP 2 demonstrates faster reaction kinetics and higher energy efficiency than the cation-ordered phase of ZnSiP 2 . The superior performance is attributed to the greater electronic and ionic conductivity and better tolerance against volume variation during cycling, as confirmed by theoretical calculations and experimental measurements. Moreover, the cation-disordered ZnSiP 2 /C composite exhibits excellent cycle stability and superior rate capability. The performance surpasses all reported multi-phase anodes studied. Further, a number of the cation-disordered phases in the Zn(Cu)–Si–P family with a wide range of cation ratios show similar performance, achieving large specific capacities and high first-cycle coulombic efficiency while maintaining desirable working potentials for enhanced safety.  more » « less
Award ID(s):
1742828
PAR ID:
10147778
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Energy & Environmental Science
Volume:
12
Issue:
7
ISSN:
1754-5692
Page Range / eLocation ID:
2286 to 2297
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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