Facile Synthesis of Ni(OH)₂/Carbon Nanofiber Composites for Improving NiZn Battery Cycling Life

Abstract

Carbon nanofibers (CNFs) were successfully functionalized by the hydrothermal treatment of wet CNFs containing concentrated HNO 3 . The method of synthesis was facile and eco-friendly. With the use of oxidized CNFs as substance, Ni(OH) 2 /oxidized CNFs hybrid materials were prepared by taking a two-step solution phase reaction. The XRD pattern and TEM image suggested a well crystalline Ni(OH) 2 nanoplate with β-phase structure growth on the surface of CNFs. Electrochemistry test results displayed high specific capacitances and long cycle life of the composites. With the use of Ni(OH) 2 / CNFs as cathode and Zn foil as anode, assembled NiZn pouch cells could achieve ∼1.75 V discharge voltage plateau, with a specific capacity ranging from 184 mAh•g −1 at a discharging current density of 5 mA•cm −2 to 91 mAh•g −1 at a discharging current density of 50 mA•cm −2 . Its cycle stability was up to 1200 cycles with a capacity retention of >96% at attaining an energy density of 150 Wh•kg −1 . Compared with a 6 mol•L −1 KOH solution electrolyte battery, the sodium polyacrylate gel electrolyte battery displayed better cycle performance. The function of the gel electrolyte was discussed. The facile method could be extended to the oxidization of the other carbon materials and synthesis of the others carbon composites.

Progress in Rechargeable Aqueous Zinc‐ and Aluminum‐Ion Battery Electrodes: Challenges and Outlook

“…In this review, we discuss rechargeable electrodes which can insert Zn 2+ ions. Since, electrodes for zinc–nickel batteries, alkaline Zn–MnO 2 batteries, or the hybrid zinc aqueous batteries, store other ions (and not Zn 2+ ), we do not discuss these systems here. Majority of the literature for ZIAB electrodes spans various polymorphs of manganese dioxide, vanadium compounds, and hexacyanoferrates, and we discuss few Zn 2+ storage mechanisms for these electrodes.…”

Ni (II) Coordination Supramolecular Grids for Aqueous Nickel‐Zinc Battery Cathodes

“…Apparently, the G‐NCGs//Zn battery exhibits better cycling stability than that of NCGs, showing that the NCGs can well synergize with GNs to reach a long lifetime (Figure 5c). The G‐NCGs//Zn battery retains 90% of its initial capacitance after 650 cycles and maintains 50% of the initial capacity after 2000 cycles, outperforming most previously reported NZBs (Figure 5d), [ 9a,37 ] for instance, Ni 3 S 4 //Zn battery (83.3% after 100 cycles), [ 14 ] Ni(OH) 2 //Zn‐Al‐LDH@ppy battery (90% after 270 cycles), [ 15a ] Co 3 O 4 @NiO//Zn battery (90% after 500 cycles), [ 15b ] NiCo 2 O 4 //Zn battery (90% after 190 cycles), [ 38 ] NiAlCo‐LDH‐CNT//Zn battery (90% after 600 cycles), [ 13b ] NiO‐CNT//Zn battery (90% after 190 cycles), [ 12a ] NiO–3D Zn battery (80% after 80 cycles), [ 4b ] Ni(OH) 2 //Zn battery (120% after 20 cycles), [ 39 ] Ni‐Zn double hydroxide battery (90% after 16 cycles), [ 11b ] and other Zn‐based batteries. [ 40 ] The SEM images for the G‐NCGs electrode after 2000 cycles (Figure S13a, Supporting Information) clearly show that the morphology of the G‐NCGs was well‐maintained.…”

Oxygen vacancies-rich cobalt-doped NiMoO4 nanosheets for high energy density and stable aqueous Ni-Zn battery

“…As is known to all, the performance of Ni-Zn batteries is dominantly determined by the intrinsic properties of electrode materials. Compared with the high theoretical capacity of Zn anode (820 mA h g −1 ), the capacities of most Ni-based cathode materials reported previously are relatively low, impeding the enhancement of energy density for Ni-Zn batteries [21][22][23]. Therefore, varieties of Ni-based materials have been intensively explored and shown improved capacities for Ni-Zn batteries, such as NiO [22], Ni(OH) 2 [24], and Ni@NiO [17].…”