Unveiling the Genesis and Effectiveness of Negative Fading in Nanostructured Iron Oxide Anode Materials for Lithium-Ion Batteries

Abstract

Iron oxide anode materials for rechargeable lithium-ion batteries have garnered extensive attention because of their inexpensiveness, safety, and high theoretical capacity. Nanostructured iron oxide anodes often undergo negative fading, that is, unconventional capacity increase, which results in a capacity increasing upon cycling. However, the detailed mechanism of negative fading still remains unclear, and there is no consensus on the provenance. Herein, we comprehensively investigate the negative fading of iron oxide anodes with a highly ordered mesoporous structure by utilizing advanced synchrotron-based analysis. Electrochemical and structural analyses identified that the negative fading originates from an optimization of the electrolyte-derived surface layer, and the thus formed layer significantly contributes to the structural stability of the nanostructured electrode materials, as well as their cycle stability. This work provides an insight into understanding the origin of negative fading and its influence on nanostructured anode materials.

Sandwich-like CoMoP2/MoP heterostructures coupling N, P co-doped carbon nanosheets as advanced anodes for high-performance lithium-ion batteries

“…S7, and it still exhibited about 530 mAh g − 1 after 900cycles with the similar phenomenon occurred. This enhanced speci c capacity was mainly as a result of the activation processes, which has been widely reported in other conversion-type and transition metal phosphide anodes for LIBs [17,47,51].…”

Amorphous Lithium-Phosphate-Encapsulated Fe2O3 as a High-Rate and Long-Life Anode for Lithium-Ion Batteries

“…As shown by Figure e, due to the lithium-driven structural modification, the pristine Fe 2 O 3 nanoparticles converted into nanocrystals with a size of 10 nm and then still evenly attached to the amorphous Li x PO 4 matrix. According to previous literature reports, these results may lead to the fluctuations of the cyclic curve . As shown by Figure f, the Fourier transform patterns of Figure e can be indexed to Fe (JCPDS: No.88–2324) and Li 2 O (JCPDS: No.…”

“…According to previous literature reports, these results may lead to the fluctuations of the cyclic curve. 50 As shown by Figure 5f, the Fourier transform patterns of Figure 5e can be indexed to Fe (JCPDS: No.88−2324) and Li 2 O (JCPDS: No. 12−0254), respectively.…”

Nano-Graphite Prepared by Rapid Pulverization as Anode for Lithium-Ion Batteries

“…The Galvanostatic lithiation/delithiation profiles of NG-3 electrodes under 5 C could be separated into three parts: (1) from the first to 20th cycle, the capacity decreases from 153.5 mAh g − 1 to 139.5 mAh g − 1 ; (2) negative fading happens from the 21st to the 350th cycle; and (3) stabilization starts from the 351st cycle, delivering a capacity of 191 mAh g − 1 . The negative fading can be mainly ascribed to the continuous consumption of lithium and electrolyte-derived surface reaction, leading to the increased capacity [ 24 ].…”