Ni-based Batteries Research Articles

Battery Technologies in Electric Vehicles: Improvements in Electric Battery Packs

Restrictions on fossil fuels and related environmental pollution issues motivate many organizations and countries to set their focus on electric vehicles (EVs) rather than conventional internal combustion engine vehicles [1], [2]. EVs require an energy storage system to store converted electric power in another form of energy and then reconvert the stored energy to electric power whenever it is required. The energy stored can be converted to electric energy for various uses, such as movement, lighting, and heating (although accessories are supplied by a 12-V auxiliary battery; the auxiliary battery is supplied by the main battery pack or by recuperative energy). Fortunately, many electrical energy storage technologies are available, with some offered commercially while others are in the research and development stage [3], [4]. Electrochemical energy storage systems use various technologies [5], [6]. Energy storage systems, the heart of EVs, are composed of battery cells, battery modules, and a battery pack. Researchers work on various sections of battery packs to improve their performance [7]. These sections are illustrated in Figure 1. As shown in the figure, some EV battery technology developers are studying chemical materials to increase the capacity, power, energy density, safety, and cell voltage. In the past century, the most common batteries for EV applications were Pb–acid and Ni-based batteries [8]. In current use, Li-ion-based batteries are at the top.

Flame Sprayed LaNi5-Based Mischmetal Alloy: Building-up Negative Electrodes for Potential Application in Ni-Based Batteries

Flame Sprayed LaNi5-Based Mischmetal Alloy: Building-up Negative Electrodes for Potential Application in Ni-Based Batteries

Exploration of Advanced Electrode Materials for Approaching High-Performance Nickel-Based Superbatteries.

The surging interest in high performance, low-cost, and safe energy storage devices has spurred tremendous research efforts in the development of advanced electrode active materials. Herein, the in situ growth of zinc-iron layered double hydroxide (Zn-Fe LDH) on graphene aerogel (GA) substrates through a facile, one-pot hydrothermal method is reported. The strong interaction and efficient electronic coupling between LDH and graphene substantially improve interfacial charge transport properties of the resulting nanocomposite and provide more available redox active sites for faradaic reactions. An LDH-GA||Ni(OH)2 device is also fabricated that results in greatly enhanced specific capacity (187 mAh g-1 at 0.1 A g-1 ), outstanding specific energy (147 Wh kg-1 ), excellent specific power (16.7 kW kg-1 ), along with 88% capacity retention after >10 000 cycles. This approach is further extended to Ni-MH and Ni-Cd batteries to demonstrate the feasibility of compositing with graphene for boosting the energy storage performance of other well-known Ni-based batteries. In contrast to conventional Ni-based batteries, the nearly flat voltage plateau followed by a sloping potential profile of the integrated supercapacitor-battery enables it to be discharged down to 0 V without being damaged. These findings provide new prospects for the design of high-performance and affordable superbatteries based on earth-abundant elements.

Intermediate phase α-β-Ni1-xCox(OH)2/carbon nanofiber hybrid material for high-performance nickel-zinc battery

Co-substituted Ni(OH)2/carbon nanofiber (CNF) composite was synthesized by chemical coprecipitation method. X-ray powder diffraction (XRD) patterns evidenced that it was an intermediate phase with α-β structure. Transmission electron microscopy (TEM) images suggested crystalline α-β-NixCo1-x(OH)2 nanosheets growth on the surface of CNFs. The testing results of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge-discharge showed that the composites had high specific capacitances, low electrochemical reaction impedance, and long cycle stability. Using the composite as a cathodic active material, a specific capacity of assembled NiZn pouch cells ranged from 160.25 mAh·g−1 at current density of 15 mA cm−2 to 91.35 mAh·g−1 at current density of 50 mA cm−2. In addition, those NiZn pouch cells have excellent rate performance and long cycle stability. After 1500 cycles, the energy capacity retained 215.24 Wh·kg−1, 98% of the initial value. The relationship between structure and the electrochemical performance was analyzed and discussed in detail. Intermediate phase α-β-Ni1-xCox(OH)2/CNF composites can be a promising cathodic active material for Ni-based batteries.

Influence of zinc additive and pH on the electrochemical activities of β-nickel hydroxide materials and its applications in secondary batteries

The importance of Ni-based batteries in the present context is extremely valuable, as their electrochemical properties are expected to offer significant insights into their application as battery materials. In this direction, Ni(OH)2 has been prepared using the co-precipitation method by varying the concentrations of zinc additive (2, 4, 6 & 8wt%) and pH (8, 9, 10 & 11). The results show that the prepared samples exist in β-phase with flake like structure. The electrochemical properties of b-Ni(OH)2 have been investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements using a paste-type electrode on a nickel mesh as a current collector. The cyclic voltammetry measurements indicate that the reversibility of the electrode reaction increases at pH 10 and 6% Zn additive. Whereas, the EIS measurements reveal that a reduction in the charge transfer resistance increases the double layer capacitance of the nickel electrode.

Polymer guided synthesis of Ni(OH)2 with hierarchical structure and their application as the precursor for sensing materials

Hierarchical Ni(OH)2 microstructures with sizes of several micrometers have been synthesized through a polymer mediated self-assembly route. The hierarchical Ni(OH)2 microstructures are built of sheet-like building blocks, which are further composed of “side to side” stacking of tiny sheet-like units. The influence of various experimental parameters on the microstructure was investigated. It is believed that the polymer, poly(sodium-4-styrene sulfonate), selectively bonded on the surface of Ni(OH)2 clusters mediates the formation of hierarchical Ni(OH)2 microstructures. In addition, through the chemical conversion of Ni(OH)2 to NiO, an oxide sensor was fabricated, which exhibits excellent gas sensing performances to ethanol and propanol, suggesting the potential applications. It is also anticipated that these Ni(OH)2 microstructures will have successful applications in Ni-based batteries, electrodes, and so on.

Fabrication of Novel Hierarchical β-Ni(OH)2 and NiO Microspheres via an Easy Hydrothermal Process

Hierarchical β-Ni(OH)2 microspheres with 6−8 μm diameter assembled from nanoplate/nanosheet building blocks were successfully fabricated via a hydrothermal process in the presence of an anion surfactant poly(ethylene glycol) 4-nonylphenyl 3-sulfopropylether potassium salt. The factors influencing the formation of hierarchical Ni(OH)2 microspheres were monitored by using SEM characterizations. The effect of hydrothermal growth temperature on the Ni(OH)2 morphology was also investigated. NiO microspheres assembled from nanoplate/nanosheet were also obtained by thermal decomposition of the as-synthesized β-Ni(OH)2 at 320 °C for 3 h in air. HRTEM and SAED results reveal that the Ni(OH)2 and NiO nanosheets are single crystalline. Nitrogen adsorption−desorption measurements of the BET surface area and pore size of NiO microspheres were 160 m2/g and 30−50 nm, respectively. It is anticipated that these novel hierarchical microsphere structures of Ni(OH)2 and NiO will have great applications in Ni-based batteries,...

Fabrication of Nickel Hydroxide Microtubes with Micro- and Nano-Scale Composite Structure and Improving Electrochemical Performance

The β-Ni(OH)2 microtubes with hierarchical structure wall composed of interweaved nanolamella were successfully fabricated by the template-free wet-chemical approach. To the best of our knowledge, it is the first report on Ni(OH)2 microtubes with the micro- and nanoscale composite structure. This method is very facile and effective to prepare the tubular materials with high yield and uniform tube diameter. The intermediate product and final composite structures were well characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform IR (FTIR), and thermogravimetric analysis (TGA), and the formation mechanism was deeply studied. In comparison with β-Ni(OH)2 microrod and particle electrodes, β-Ni(OH)2 microtube electrode has the highest discharge capacity in alkaline battery, indicating the potential applications of the microtubes with the hierarchical structures in alkaline Ni-based batteries, supercapacitor, and catalytic areas.

Oxygen Evolution and Recombination Kinetics Inside Sealed Rechargeable, Ni-Based Batteries

The oxygen evolution and recombination kinetics in Ni-based battery systems have been investigated under temperature-controlled, steady-state, overcharging conditions within a temperature range of . Theoretical relationships for both reactions have been derived. The mathematical relationships have been confirmed by experiments on sealed rechargeable NiCd batteries. Under steady-state overcharging conditions, the Cd electrode potential was proven to be constant, thereby significantly reducing the complexity of the interpretation of the results. The oxygen evolution reaction was found to be a two-step process at the Ni electrode: two linear Tafel dependencies were found at low and high currents, separated by a transition region at intermediate currents. The oxygen recombination kinetics was found to be first-order in partial oxygen pressure, strongly suggesting that the recombination reaction is purely diffusion-controlled by oxygen, redissolved into the electrolyte, to the Cd electrode surface. For all reactions, activation energies have been determined. The results can directly be applied to aqueous battery models and give more insight into both the overcharging and self-discharge processes occurring in these Ni-based systems.

Fabrication of Hollow Spheres and Thin Films of Nickel Hydroxide and Nickel Oxide with Hierarchical Structures

Hollow spheres and thin films of Ni(OH)(2) and NiO with unusual form and hierarchical structures have been synthesized by a simple solution chemistry method. First, in situ formed Ni(OH)(2) nanoflakelets organized on the surface of styrene-acrylic acid copolymer (PSA) latex particles to form core/shell structures. Ni(OH)(2) hollow shells built up with nanoflakelets were obtained after subsequent removal of the core latex particles by dissolving PSA latex in toluene; the removal of the cores by calcinations would result in NiO hollow shells, also with hierarchical structures. BET calculation showed the surface area of the NiO hollow spheres was 156 m(2)/g. The nanoflakelets could also organize themselves into thin films with hierarchical structures. It is anticipated that these novel structures will have some unique applications in Ni-based batteries and other potentials.

New Approaches for Synthesizing γIII‐CoOOH by Soft Chemistry.

AbstractFor Abstract see ChemInform Abstract in Full Text.

New Approaches for Synthesizing γIII-CoOOH by Soft Chemistry

Two soft chemical processes enabling the low-temperature synthesis of γIII-CoOOH are reported. Both processes consist of an oxidation reaction of αII-Co(OH)2 performed either in dry conditions (ozonation) or in solution. The γIII-CoOOH phase is usually prepared using a ceramic step process, which hinders its synthesis as a coating to improve the electrochemical performance of the active nickel hydroxide positive electrode in Ni-based batteries. Through this work, new γIII-CoOOH phases presenting properties quite different from those of the ceramic γIII-COOOH are obtained. The chemical stability in concentrated potassium hydroxide solution and the electrochemical behavior of these new phases have also been studied.

Pasted Ni ( OH ) 2 Electrodes Using Ni Powders for High-Drain-Rate, Ni-Based Batteries

Experimental work was carried out to explore the possibility of using filamentary Ni powder to enhance the rate capability and reduce the usage of cobalt in pasted electrodes for high-drain-rate application. Testing results showed that an extra fine filamentary nickel powder, type 210, as an additive significantly improved the active mass utilization, gravimetric capacity, and volumetric capacity of pasted electrodes at high rates. In addition, the performance gain could be achieved in thicker electrodes using reduced Co content. Coarser filamentary Ni powder, type 255, was also found effective but in a lesser degree than type 210. The major contribution of a filamentary Ni powder was believed to be enhancement of conductivity by means of a secondary conductive network in the active mass within the Ni foam cells, equivalent to a reduction in Ni foam cell size. © 2003 The Electrochemical Society. All rights reserved.

Competition between the Two Reduction Reactions of the γ(III) Phase in the Ni-Based Batteries

We show that the γ(III)/β(II) phase transition is at the origin of the second plateau at 0.8V in the Ni-based batteries by means of transmission electron microscopy (TEM) and X-ray diffraction (XRD) studies and intermittent galvanostatic measurements (GITT). This study shows that the equilibrium voltage of this transition is 1.25V vs Cd-Cd(OH)2, thus implying an overvoltage of 400 mV. Direct evidence for a textural memory effect trough the γ(III)/β(II) phase transition is given by TEM studies. The reoxidation of the β(II) phase to γ(III) phase occurs without going trough the β(III) phase.