Recycling of Li−Ni−Mn−Co Hydroxide from Spent Batteries to Produce High‐Performance Supercapacitors with Exceptional Stability

Abstract

The intensive implementation of Li‐ion batteries in many markets makes it increasingly urgent to address the recycling of strategic materials from spent batteries. Batteries typically contain toxic chemicals and cannot be disposed of at will. In this study, Li−Ni−Mn−Co hydroxides are successfully recycled from spent Li‐ion batteries electrodeposited on nickel foam, and fully characterized using different techniques such as field emission scanning electron microscopy (FESEM), X‐ray diffraction (XRD), energy dispersive X‐ray spectroscopy (EDXS), inductively coupled plasma (ICP), and X‐ray photoelectron spectroscopy (XPS) techniques. The recycled nanostructured films are tested in a three‐electrode electrochemical system to investigate their capacitance behavior. The recycled electrodes show high capacitance of 951 F g−1 (specific capacity of 523.5 C g−1) at 1 A g−1. Moreover, the recycled materials are used as positive electrodes to construct asymmetric supercapacitor devices. The device shows a coulombic efficiency of 100 %, a capacitance retention reaching approximately 90 % with excellent cycling stability after 10 000 cycles as well as reasonable power and energy densities.

Oxygen Vacancy‐Engineered Ti−Mo−Ni Ternary Oxide Nanotubes as Binder‐Free Supercapacitor Electrodes with Exceptional Potential Window

“…The semicircle diameter indicates the charge transfer resistance (R CT ) to the redox reaction, whereas the high frequency intercept on the X-axis reveals the series resistance (R Ω ), which includes electrolyte resistance, the internal resistance of the active material, and the contact resistance at the solid-liquid interface. [52,53] The R ct and R Ω for the air-annealed and H 2 -treated TiÀ MoÀ NiÀ O nanotubes were found to be 1.34 and 0.83 Ω, respectively. From the Bode plot (Figure 4f), the estimated time constant for the hydrogenannealed TiÀ MoÀ NiÀ O nanotubes is 8.2 ms, which is significantly lower than that estimated for the air-annealed counterpart (18.1 ms).…”

Fullerene C76: An Unexplored Superior Electrode Material with Wide Operating Potential Window for High‐Performance Supercapacitors

“…In the positive potential window, C 76 showed different responses in the three electrolytes, as indicated via the cyclic voltammograms (CVs) at a scan rate of 10 mV/s shown in Figure (A). While C 76 showed clear reversible peaks in H 2 SO 4 electrolyte for the oxidation and reduction processes at ∼0.45 V SCE (∼0.69 V SHE ), it showed an equirectangular shape reflecting either an EDL behavior or a surface pseudocapacitive behavior in Na 2 SO 4 and the KOH electrolytes . Therefore, C 76 seems to undergo redox reactions in H 2 SO 4 electrolyte only.…”

“…A typical supercapacitor device mainly depends on the adsorption/desorption of ions on its surface, namely the electrical double layer (EDL). Moreover, developments included the use of Faradic materials such as the diffusion‐controlled pseudo and the redox battery‐like capacitors . Although Faradic materials can deliver high energy density, they suffer from poor cycling stability compared to the EDL counterparts.…”

Supercapacitors in the Light of Solid Waste and Energy Management: A Review

“…Benign materials retrieved from carbon-rich agricultural and food biowaste, [9,105,115,116] industrial waste, [76][77][78][79] paper, [74,80,81] and cotton [82] have been used in their fabrication. Additionally, carbon acquired from discarded polymers [83][84][85][86][87][88][89][90][91][92][93][94][95] as well as valuable metals and metal composites recuperated from electronic waste including spent batteries [96][97][98][99][100][101][102] have been utilized in the preparation of supercapacitor electrodes. Contemporarily, the global awareness for a sustainable future has seen the evolution of novel electrolytes for these devices.…”