Water Invoking Interface Corrosion: An Energy Density Booster for Ni//Zn Battery

Abstract

Advanced Ni//Zn batteries possess great promise that combines battery‐level energy density and capacitor‐level power density. However, the surface chemical reactivity of the cathode is generally restricted by active material utilization, leading to an insensitive edge site and unsatisfactory capacity. Herein, a simple and energy‐saving strategy is reported for manipulating the bimetallic sulfide nanointerfaces via water invoking interface corrosion to achieve a 200% increase in the capacity of electrodes. The combined action of water and oxygen causes secondary in situ growth of NiCo–OH nanosheet coating layers on the CoxNi3‐xS2 nanowalls with surface enrichment of low‐valence mixed states, which deliver remarkable reactive activity and structural stability. As a result, the 3D cathode yields an ultrahigh capacity of 2.45 mAh cm−2, higher than that of the pristine nanomaterial (1.20 mAh cm−2). The resulting Ni//Zn battery with excellent reversibility and long‐life, achieves a remarkable energy density of 4.29 mWh cm−2 (728 Wh kg−1), which is superior to most recently reported aqueous Zn‐based batteries and is even comparable to Li‐ion batteries. This work explores the interface corrosion mechanism and corrosion‐surface activity relationship, which is a powerful strategy to construct high surface electrochemical activity of metallic sulfides/phosphides for renewable energy storage devices.

Oxygen-Defect Enhanced Anion Adsorption Energy Toward Super-Rate and Durable Cathode for Ni–Zn Batteries

“…To date, various alkaline Zn-based cathodes have been developed, such as MnO 2 [9], Ag-based [10], and Ni, Cobased materials (e.g., Ni(OH) 2 [11,12], NiO [13], NiSe 2 [14], Ni 3 S 2 [15,16], Co 3 O 4 [17][18][19], Co 3 S 4 [20], NiCo-DH [21,22], and NiCo 2 O 4 [23][24][25]). While MnO 2 -Zn battery has a low working voltage and weak stability, AgO-Zn battery has low stability, poor overcharge tolerance and high cost.…”

MOF-derived NiCo2S4 and carbon hybrid hollow spheres compactly concatenated by electrospun carbon nanofibers as self-standing electrodes for aqueous alkaline Zn batteries

“…3e, in which the peaks at 163.5 and 164.7 eV are associated with S 2p 3/2 and S 2p 1/2 . 44,45 In Fig. 3f, the tted N 1s spectrum can be resolved into three components, corresponding to pyridinic N (398.9 eV), pyrrolic N (400.3 eV) and graphitic N (401.9 eV), respectively.…”

“…Compared with Ni/Co-based oxide and hydroxide counterparts, bimetallic NiCo 2 S 4 is more appealing as a cathode material by virtue of the higher electrical conductivity and better electrochemical activity. 36,[44][45][46] The assynthesized NiCo 2 S 4 /HCS@CF lm cathode has many apparent advantages: (1) the hollow and porous structure can provide more reaction active sites and facilitate the ion diffusion; (2) the NiCo 2 S 4 nanoparticles are tightly coupled with the carbon to enhance the electrical conductivity; (3) the electrospun NiCo 2 S 4 /HCS@CFs are interwoven with each other, which can enhance the structural stability; (4) the free-standing NiCo 2 S 4 /HCS@CF lm as a cathode electrode is free of any binder and conductive carbon. As a result, the self-standing NiCo 2 S 4 /HCS@CF cathode manifests remarkable electrochemical performance in terms of high discharge capacity (343.1 mA h g À1 at 3.8 A g À1 ), as well as superior rate capability and decent cycling performance.…”

A Novel Method to Prepare Flexible 3D NiO Nanosheets Electrodes for Alkaline Rechargeable Ni−Zn Batteries

“…The semicircle curve in the high‐frequency area is associated with the charge‐transfer resistance ( R ct ) in electrode materials [3,19] . And, the slanted linear in the low‐frequency region corresponds to Warburg impedance ( R w ), which is related to the diffusion of ions at the electrode/electrolyte interface [3b] . The corresponding fitting result indicates that the NiO/PNF displays the lowest equivalent series resistance ( R s ) of 0.4 Ω and R ct of 10.4 Ω, lower than that for Ni(OH) 2 /PNF ( R s , 0.56 Ω, R ct , 35.8 Ω).…”