(176844)Coordinate regulation of amorphous carbon microspheres and crystal structure of iron oxalate for high rate lithium storage ability

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作   者：

Keqi Chen;  Zengmou Li;  Keyu Zhang; 

作者机构：

China;  Kunming 650093;  National Engineering Research Center of Vacuum Metallurgy;  Faculty of Metallurgy and Energy Engineering;  Kunming University of Science and Technology; 

关键词：

Iron oxalate;  Phase transformation;  Lithium-ion battery;  Amorphous carbon microspheres;  Recrystallization; 

期刊名称：

Journal of Alloys and Compounds

i s s n：

0925-8388

年卷期：

2024 年 1008 卷

页   码：

1-15

页   码：

摘   要：

Iron oxalate is one of the highly potential anode materials for lithium-ion batteries, but its widespread application is limited by slow electron transfer rate and sluggish electrochemical reactions. Herein, iron oxalate/ amorphous carbon microspheres (FeC2O_4/PCC) composite with uniformly mixed crystalline phase for more stable active sites and three-dimensional conductive network, was synthesized via the in-situ self-polymerization, carbonization of β-cyclodextrin and recrystallization technique under solvothermal condition. The self-aggregation progress and kinetics of recrystallization accelerate the crystalline phase transformation of iron oxalate and the morphology reconstruction of micron-grade polygonal prism particles. Based on the fast electron migration facilitated by three-dimensional conductive network of PCC and exceptionally stable structure and Li~+ diffusion channels endowed by strengthening effect of recrystallization, FeC2O_4/PCC-15 % exhibits long cycling life and outstanding ability for high-rate lithium storage: the specific capacities of 1231.50 and 1128.75 mAh g~(-1) after 500 cycles at current densities of 3 and 5 A g~(-1), with capacity retention rates of 90.79 % and 81.08 %, respectively. Furthermore, according to electrochemical capacity contribution analysis, PCC also can remarkably enhance the reversible lithium storage ability of interfacial capacitive effects and conversion reaction even under high current density. This work provides a new modification pathway for the application of transition metal oxalate systems in fast charging field.