Anode Electrodeposition of Fe/Fe₃O₄ composite on Carbon Fabric as a Negative Electrode for Flexible Ni−Fe Batteries

Abstract

The nickel-iron (NiÀ Fe) battery is a competitive alternative for electrochemical energy storage, owning to its low cost, high safety, and strong auto-adaptive ability. However, the selfdischarge and passivation of the negative electrode are the two main issues. In this work, a rock-like Fe/Fe 3 O 4 composite is synthesized and deposited on carbon fabric (Fe/Fe 3 O 4 @CF) by facile electrodeposition and annealing technologies to serve as a binder-free anode, which exhibits a large areal capacity of 0.466 mAh cm À 2 and long-term cycling durability. Moreover, the flexible device is assembled by employing Fe/Fe 3 O 4 @CF-750 as anode and Ni(OH) 2 @CF as cathode. The above battery displays an enhanced operating voltage up to 1.7 V, impressive mechanical flexibility, outstanding cycling stability (86.2 % retention of initial value over 6000 charge-discharge cycles), and satisfactory voluminal capacity of 1.33 mAh cm À 3 , indicating its potential application for energy supply systems of modern wearable electronics.

High–Performance Biscrolled Ni–Fe Yarn Battery with Outer Buffer Layer

“…Even at 7535 mW/cm 3 , the energy density was 229 mWh/cm 3 . Thus, the proposed b–BNF yarn battery outperforms most previously reported Ni–Fe batteries ( Figure 3 d) [ 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 ].…”

“…( c ) Capacity retention and corresponding coulombic efficiency of b–BNF yarn battery. ( d ) Ragone plot of as–fabricated Ni–Fe battery (based on total volume of the cathode and anode) [ 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 ]. ( e ) Photographs showing three b–BNF yarn batteries woven into a commercial textile.…”

Effect of alkali metal cations in alkaline iron battery electrodes

“…The oxidation and reduction peaks shifted toward more positive and negative potentials respectively as the scan rate increased. Furthermore, a linear relationship between the peak current densities and the square root of the scan rates implies that the redox reaction is diffusioncontrolled [11].…”

A Tale of Nickel-Iron Batteries: Its Resurgence in the Age of Modern Batteries

“…Achieving an ideal combination of reinforcement and matrix materials has drawn a lot of interest in improving the performance of Fe electrodes. Various reinforcement materials have been explored, including transition metals [97,109], metal oxides [48,86,112], intermetallic compounds [48], and carbon. Transition metals (TM) and their oxides are known for their high theoretical capacity, ideally making them good reinforcements for Febased composites.…”

“…With Fe's propensity to undergo multivalent oxidation, several studies attempted to pair Fe with its oxides to address issues on volume changes and cycling stability caused by the existence of different valence states. Zhu et al [112] electrodeposited and then thermally annealed a rock-like Fe/Fe 3 O 4 on carbon fiber to produce a stable mesoporous microstructure. The resulting material had a capacity of 160 mAh g −1 at 3.43 A g −1 and maintained a rate capability of 90.32 mAh g −1 after being discharged three times its initial capacity.…”