Free-standing Fe2O3 nanomembranes enabling ultra-long cycling life and high rate capability for Li-ion batteries

Abstract

With Fe2O3 as a proof-of-concept, free-standing nanomembrane structure is demonstrated to be highly advantageous to improve the performance of Li-ion batteries. The Fe2O3 nanomembrane electrodes exhibit ultra-long cycling life at high current rates with satisfactory capacity (808 mAh g−1 after 1000 cycles at 2 C and 530 mAh g−1 after 3000 cycles at 6 C) as well as repeatable high rate capability up to 50 C. The excellent performance benefits particularly from the unique structural advantages of the nanomembranes. The mechanical feature can buffer the strain of lithiation/delithiation to postpone the pulverization. The two-dimensional transport pathways in between the nanomembranes can promote the pseudo-capacitive type storage. The parallel-laid nanomembranes, which are coated by polymeric gel-like film and SEI layer with the electrolyte in between layers, electrochemically behave like numerous “mini-capacitors” to provide the pseudo-capacitance thus maintain the capacity at high rate.

Fe3O4/carbon nanofibres with necklace architecture for enhanced electrochemical energy storage

“…[17][18][19][20] Meanwhile, commercially mature carbon nanofibres (CNFs) have also received interest in electrochemical energy storage systems because when mixed into an electrode their high aspect ratio and good electrical conductivity efficiently percolate electrical current at low fraction. [17][18][19][20] Meanwhile, commercially mature carbon nanofibres (CNFs) have also received interest in electrochemical energy storage systems because when mixed into an electrode their high aspect ratio and good electrical conductivity efficiently percolate electrical current at low fraction.…”

“…Some of these configurations similarly make use of intimate contact between fine-scale Fe 3 O 4 and a carbon-based electron carrier. The specific capacity and Coulombic efficiency at 0.05 C as a function of 19 cycle number are shown in Figure 7b with capacity reduced primarily in the first 3 cycles only, and then remaining stable with a reversible capacity of 836 mAh g -1 after 100 cycles. When current densities up to 10 A g -1 are considered, the current work is only approached by Reference [4] in the ESI, but which involved an additional, decomposition of electrolyte, which are frequently observed for most anodes.…”

Generalized Synthesis of Metal Oxide Nanosheets and Their Application as Li‐Ion Battery Anodes

“…In addition, the experimental methodology varied from one oxide to the other, which prohibits the development of a generalized synthesis method. They usually use corrosive solutions such as NaOH, [10,[26][27][28] which renders their methodology laborious. Several templates were studied for metal oxide nanosheet synthesis such as G-SiO 2 , [26][27][28] graphene oxide (GO), [29,30] and inverse lamellar micelles.…”

“…[8,9] In particular, the unique structure of the nanosheet is expected to improve Li-ion battery performance. [10][11][12][13] The ultrathin nanosheet thickness promotes Li + and electron transport across the material, yielding higher rate capability. [10][11][12][13] The ultrathin nanosheet thickness promotes Li + and electron transport across the material, yielding higher rate capability.…”

“…[10][11][12][13] The ultrathin nanosheet thickness promotes Li + and electron transport across the material, yielding higher rate capability. The special surface electronic structure of the nanosheets [10,12,15] may also give rise to unique properties such as pseudocapacitive behavior. The special surface electronic structure of the nanosheets [10,12,15] may also give rise to unique properties such as pseudocapacitive behavior.…”