Charge-discharge Current Density Research Articles

Real-Time Monitoring of the Thermal Effect for the Redox Flow Battery by an Infrared Thermal Imaging Technology

In this study, a new monitoring method was developed, titled infrared thermal imaging technology, which can effectively evaluate the thermal effect of the charge-discharge test in the vanadium/iodine redox flow battery (V/I RFB). The results show that the all-vanadium redox flow battery (all-V RFB) has a greater molar reaction Gibbs free energy change than that of the V/I RFB, representing a large thermal effect of the all-V RFB than the V/I RFB. The charge-discharge parameters, flow rate and current density, are important factors for inducing the thermal effect, because of the concentration polarization and the ohmic resistor. The new membrane (HS-SO3H) shows a high ion exchange capacity and a good ions crossover inhibitory for the V/I RFB system, and has a high coulomb efficiency that reaches 96%. The voltage efficiency was enhanced from 61% to 86% using the C-TiO2-Pd composite electrode as a cathode with the serpentine-type flow field for the V/I RFB. By adopting the high-resolution images of an infrared thermal imaging technology with the function of the temperature profile data, it is useful to evaluate the key components’ performance of the V/I RFB, and is a favorable candidate in the developing of the redox flow battery system.

Enhancing of Electrochemical Characteristics of Li-S System by Means of Optimization of Sulfur Electrode and Electrolyte Composition

The article discusses the influence of technological parameters of sulfur electrodes and the concentration composition of the salt-solvation electrolytes TEGDME–LiTFSI on the specific characteristics of Li-S cells obtained under galvanostatic cycling conditions. The dependences of the specific capacity on the composition of the cathode, the charge-discharge current density, as well as capacity retention upon storage are discussed.

Maghemite-based anode materials for Li-Ion batteries: The role of intentionally incorporated vacancies and cation distribution in electrochemical energy storage

Anode materials for Lithium-Ion Batteries (LIBs) based on Mo- and V-doped maghemite were prepared by the sol-gel route. High-Resolution Transmission Electron Microscopy (HRTEM) showed the formation of isotropic nanoparticles. The X-ray Photoelectron Spectroscopy (XPS) revealed the presence of Fe3+ and Mo6+ or V4+ for Mo- or V-doped samples, respectively. Rietveld refinement of X-ray Diffraction (XRD) patterns revealed the distribution of Mo6+ and V4+ cations and showed increase in vacancies. The crystallite size resulted from Rietveld adjustments was in agreement with the HRTEM results. The Extended X-ray Absorption Fine Structure (EXAFS) showed a shrinkage of Fe–O–Fe linkages which is responsible for the reduction of the maghemite cell parameter which agreed with the structural analysis from XRD. The X-ray Absorption Near Edge Structure (XANES) confirmed XPS analysis that Fe3+ is present. Coin cells were assembled and galvanostatic cycling was implemented at various charge-discharge current densities, cyclic voltammograms of Li-ions insertion/extraction processes were obtained and the Electrochemical Impedance Spectroscopy (EIS) was investigated. An exceptional cyclic stability and storage capacity for the V-doped maghemite was observed for low current density. The Mo-doped maghemite has higher capacity retention at high current densities.

Electrochemical hydrogen storage behavior of Ni-Ceria impregnated carbon micro-nanofibers

A hierarchical porous structured carbon micro-nanofiber containing the bimetallic configuration of the nickel (Ni) and ceria (CeO2) nanoparticles (NPs) was synthesized and tested for the electrochemical hydrogen (H2) storage capacity. The electrode exhibited a high H2 storage capacity of 498 mA h/g or 1.858% (w/w) at the charge-discharge current density of 500 mA/g. A mechanistic insight showcased the combined contributions of the high surface area containing activated carbon microfiber (ACF) substrate, the graphitic carbon nanofibers (CNFs), and the Ni and CeO2 NPs, towards the augmented electrochemical H2 storage capacity and cyclic stability of the fabricated Ni–CeO2–CNF/ACF electrode. Ni served as the catalyst for growing the CNFs via chemical vapor deposition as well as for storing H2 via spillover mechanism, while CeO2 created the charge carrier vacancies in the material. The measured cycle retention capacity of 99% and charge-discharge efficiency of 97.6% confirm the electrochemically stable characteristics of Ni–CeO2–CNF/ACF, and clearly indicate it to be an economically viable and efficient H2-storage material.

Hierarchically porous carbon derived from potassium-citrate-loaded poplar catkin for high performance supercapacitors

A simple one-step preparation of biomass derived carbon materials with hierarchical pore structure for supercapacitor application is proposed. Briefly, potassium citrate is loaded onto poplar catkin, a forestry and agricultural residue, for carbonization at different temperature (750–900 ℃). With the confined effect of poplar catkin and pore-forming role of potassium compounds, interconnected carbon networks combining of macropores, small mesopores and micropores are obtained. The product carbonized at 850 ℃ (S-850) processes large surface area of 2186 m2/g with two main micropore ranges distributed in 0.5–0.7 nm and 0.7–1.5 nm, and the sample of S-900 processes relatively high electrical conductivity because of the high degree of graphitization. The electrodes based on these carbon materials show main electrical double-layer capacitors with small part of pseudo-capacitors due to O-doping. The S-850 sample displays superior specific capacity at low charge–discharge current density while the electrode based on S-900 shows high specific capacity under high current density. The symmetrical devices based on S-850 give a superb stability and high energy and power densities in alkaline electrolyte. Within a voltage window of 1.4 V, the device can deliver a 13.3 Wh/kg energy density at a power density of 720 W/kg and maintain 7.8 Wh/kg at 14040 W/kg.

Synergistic effects of niobium oxide–niobium carbide–reduced graphene oxide modified electrode for vanadium redox flow battery

A powerful, low-cost niobium oxide–niobium carbide–graphene oxide (NbO2/NbC/rGO) hybrid electrocatalyst is prepared by refluxing, hydrothermal method, followed by annealing process at the optimum temperature of 1050 °C for all vanadium redox flow battery (VRFB) application. The NbO2/NbC/rGO electrocatalyst shows the best electrochemical activity with the highest peak current densities and the lowest peak differences toward VO2+/VO2+ and V2+/V3+ redox reactions from the cyclic voltammetry compared to other samples. The rate performance of VRFB cell using NbO2/NbC/rGO modified graphite felts (NbO2/NbC/rGO/GF) shows the voltage efficiencies of 89.3%, 81.7%, 71.0%, and 59.3% by the charge-discharge current densities of 40 mA cm−2, 80 mA cm−2, 120 mA cm−2, and 160 mA cm−2, respectively, which these performances are superior to those using the pretreated GFs and the untreated GF. The charge-discharge stability test of the VRFB cell using NbO2/NbC/rGO/GF demonstrates no significant decay after 100 cycles by the current density of 80 mA cm−2. This observation is due to the synergistic effects related to the presence of excess oxygen vacancies on NbO2/NbC, the high content of oxygen functional groups, and the high electrical conductivity characteristics of the graphene sheet.

Improved Capacitive Performances from Adjusted Graphite Microcrystallites with Multilayer Graphene Being In Situ Formed in Amorphous Carbons

The adjusted graphite microcrystallites (GMCs) in amorphous carbons have an important effect on their structures and capacitive performances. Samples with various accumulations of GMCs are prepared from carbon microspheres (CMSs). Their structures and capacitive performances are probed by morphology, spectroscopy, nitrogen adsorption–desorption, and electrochemical methods. The carbons with multilayer graphene (MLG) being in situ formed possess the specific surface area, mesopore volume, and specific capacitance of about 2087 m2 g−1, 0.92 cm−3 g−1, and 250 F g−1, which is 2.33, 8.4, and 1.9 times larger than CMSs, respectively. The combination of ordered and disordered GMCs results from MLG being in situ formed in amorphous carbons, and makes the carbons possess obviously decreased electric and ionic transmission resistances and improved capacitive performances at large charge–discharge current densities. It is also found that the accumulation of GMCs in amorphous carbons can be adjusted by controlling the infiltration of sodium metals into the matrix.

Investigations on physicochemical properties and electrochemical performance of graphite felt and carbon felt for iron‐chromium redox flow battery

In this paper, polyacrylonitrile-based graphite felt (GF), carbon felt (CF) and the effect of thermal activation on them with or without the catalyst (BiCl3) are comprehensively investigated for iron-chromium redox flow battery (ICRFB) application. The physical-chemical parameters of GF and CF after the thermal activation is affected significantly by their graphitization degree, oxygen functional groups, and surface area. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results manifest that GF and CF before and after the thermal activation have different electrocatalytic activities owing to oxygen functional groups number increase and the graphitization degree decrease. In terms of the capacity decay rate, as oxygen functional groups provide shorter electrocatalytic pathways than bismuth ions, the performance of GF and CF after the thermal activation is more ideal. As a result, GF before and after the thermal activation exhibits higher efficiency (EE: 86%) and better stability at a charge-discharge current density of 60 mA·cm−2 than those of CF during charge-discharge cycling, as the dominant limitation in an ICRFB is ohmic and activation polarization. Therefore, GF after thermal activation together with the addition of BiCl3 in the electrolyte is a more promising electrode material for ICRFBs application than CF.

Functionalization of textile cotton fabric with reduced graphene oxide/MnO2/polyaniline based electrode for supercapacitor

In this work, a new cotton electrode has been synthesized by coating ternary materials of reduced graphene oxide (rGO), manganese dioxide (MnO2), and polyaniline (PANi) on textile cotton fabric. First, Graphene oxide was deposited on cotton fibers by a simple ‘dip and dry’ method and chemically reduced into rGO/cotton fabric. MnO2 nanoparticles were accumulated on rGO/cotton fabric by in situ chemical deposition method. PANi layer was coated on rGO/MnO2/cotton fabric by in situ oxidative polymerization technique. A thin PANi coating layer acts as a protective layer on rGO/MnO2/cotton fabric to restrain MnO2 nanoparticles and rGO from dissolution in H2SO4 acidic electrolyte. The specific surface area of cotton electrode was measured using the Brenauer-Emmett-Teller (BET) method. The cyclic voltammetry (CV) results show that the cotton electrode has good capacitive behavior. The ternary cotton electrode exhibits high specific capacitance values of 888 F g−1 and 252 F g−1 at a discharge current density of 1 A g−1 and 25 A g−1 in 1 M H2SO4 electrolyte solution. The high areal specific capacitance of 444 Fcm−2 was achieved for as-fabricated electrode. Also, the cotton electrode retains around 70% of specific capacitance after 3000 cycles at charge-discharge current density of 15 A g−1. The slow decrease in specific capacitance is observed with increased discharge current density which proves its excellent rate capability. These results of rGO/MnO2/PANi/cotton fabric electrode show that this can be an excellent electrode for supercapacitor in energy storage devices.

Boosting the electrochemical performance of polyaniline based all-solid-state flexible supercapacitor using NiFe2O4 as adjuvant

Polyaniline (PANI) as supercapacitor electrode component has received increasing attention due to its high theoretical capacitance, ease of preparation and offers flexibility to fabricate device at low cost. However, PANI suffers from large volume change during doping-dedoping process, and the structural instability becomes more severe at high current and on repetitive cycling, which create challenges in replicating the theoretical capacitance in practical device form. Herein, we demonstrate the fabrication of a PANI based stable and high performance supercapacitor electrode by engineering PANI nano-architecture with NiFe2O4 (NF) nanoparticles. Notably, the optimized composite electrode showed outstanding stability over the pristine PANI electrode for a wide range of charge-discharge current density (1–10 mA/cm2). An all solid state flexible symmetric supercapacitor was fabricated using the optimized composite electrode, which showed high specific and areal capacitance of 334 F/g and 668 mF/cm2, respectively at 1 mA/cm2 current density. The device also showed excellent cyclic stability with only 1.07 ∗ 10−3% capacitance loss per cycle for tested >7000 cycles. Noteworthy, the fabricated device showed even higher capacitance when folded and under pressure applied, indicating its suitability to be used in flexible and bendable devices.

Nanostructure NiCo2S4 with different morphologies grown on Ni foam for high-performance supercapacitors

Cobalt–nickel sulfide (NiCo2S4) was directly grown on nickel foam by a facile hydrothermal method. The effect of four different sulfur sources, the composite step and RGO density on the morphology and electrochemical performance of NiCo2S4 electrode for supercapacitor were investigated in detail. The results exhibited that under the same conditions, using the thioacetamide as the sulfur source, the electrochemical properties of the electrode material was the best, which combined with 0.1 g/L RGO in the second step of hydrothermal. It showed the highest capacity and longest cycling life, demonstrating a specific capacitance of 1733 F/g at a charge–discharge current density of 1 A/g and 87% capacitor retention rate after 5000 cycles.

Preparation and properties of quaternized poly(phthalazinone ether ketone ketone) anion-exchange membrane for all-vanadium redox flow battery

As one of stationary energy storage device, all-vanadium redox flow battery (VRB) could effectively balance the relationship of electricity generation and demand side, in which interests are based on having features of high efficiency, flexible design, low cost and so on. Ion exchange membrane is one of the key components of VRB, separating redox-active ions and allowing the transfer of non-reaction species. Nafion series from Dupont company could ideally satisfy the requirements of high conductivity and good stability but facing the disadvantages of poor vanadium blocking ability in VRB. Modified Nafion membranes partially conquered the problem of poor ion selectivity but still suffering from high cost. Cationic exchange membranes prepared from non-fluorinated polymers have lower vanadium ion permeability and cost while cationic exchange groups hinder the further improvement of vanadium ion blocking. On the contrary, anionic exchange membranes (AEMs) exhibit low vanadium ion diffusion coefficient because of Donnan exclusive effection. It is much of importance to explore new AEMs. And the lifetime of the VRB cell depends on the selectivity and stability of the membranes to some degree. However, most of ion exchange membranes for VRB application showed low selectivity or stability. In order to improve the selectivity of ion exchange membranes, poly(phthalazinone ether ketone ketone) containing bromomethyl moieties (BPPEKK) with varied content of bromomethyl were dissolved to prepare BPPEKK base membranes using solution casting method. Quaternized poly(phthalazinone ether ketone ketone) (QBPPEKK) anion-exchange membranes were prepared from the amination of BPPEKK membranes in trimethylamine aqueous solutions. The measured ion exchange capacity (IEC) values of QBPPEKK membranes were in the range of 1.15–1.51 mmol/g, which were lower than the theoretical IEC (IECT) values. The result indicated the incomplete amination reaction of bromomethyl groups with trimethylamine. Properties of QBPPEKK membranes including water uptake, swelling ratio, area resistance and vanadium ion permeability were investigated. Water uptake and swelling ratio of QBPPEKK membranes increased with the increase in content of bromomethyl in BPPEKK, while area resistance and vanadium ion permeability decreased. The vanadium ion mass transfer coefficient of QBPPEKK membranes was in the range of 2.3×10-5 –5.0×10-5 cm/min, less than that of Nafion 117 membrane (11.9×10-5 cm/min). QBPPEKK membranes showed much lower vanadium ion permeability than Nafion 117. VRB with each QBPPEKK membrane showed higher columbic efficiency (CE) than the battery with Nafion117 membrane. QBPPEKK membrane with higher IEC exhibited higher voltage efficiency and energy efficiency (EE). When the content of bromomethyl reached 0.99, the VRB with QBPPEKK90 membrane had EE of 87.7% (current density: 40 mA/cm2), higher than that of Nafion117 membrane (86.0%). When the charge-discharge current density increased from 20 to 80 mA/cm2, the CE of VRB with QBPPEKK90 membrane increased from 97.1% to 99.0%, and EE of VRB cell with QBPPEKK90 decreased from 91.1% to 80.2%. After QBPPEKK membranes were immersed in VO2+ solution for 60 d, the tensile strength of the membranes was more than 36 MPa, which was lower than that of the original QBPPEKK90 membrane. There were no significant changes on microstructure of QBPPEKK membrane after the membrane had been immersed into 1.5 mol/L VO2+ solutions for 60 d. Compared with the original QBPPEKK90 membrane, CE changed slightly and EE decreased 1.4% at the charge-discharge current density ranging from 20 to 60 mA/cm2 after the membrane was immersed in VO2+ solution for 60 d. The results suggested that QBPPEKK membranes showed good chemical stability.

CoO nanorod arrays on carbon nanotube foams fabricated by reducing carbon dioxide as high-performance electrode materials for Li-ion batteries

We have successfully synthesized 3D carbon nanotube foams through a simple self-assembly method. Taking these carbon nanotube foams as substrates, we have fabricated a novel core-shell structure of CNTF@CoO through a simple heat treatment process. The electrochemical measurements suggest that the composite has excellent electrochemical performances. It shows excellent rate properties and long-term cycling stability with a reversible capacity of about 820 mAh g−1 at the charge-discharge current density of 100 mA g−1. The capacity is as large as 448 mAh g−1 after 1000 cycles at 5000 mA g−1. The excellent performance can be attributed to the high capacity of CoO, the porous structure, and high conductivity of the carbon materials that provides fast ion transport pathways and relieves the strain during charge-discharge process.

Porous core–shell CoMn2O4 microspheres as anode of lithium ion battery with excellent performances and their conversion reaction mechanism investigated by XAFS

Porous core-shell CoMn2O4 microspheres of ca. 3-5 μm in diameter were synthesized and served as anode of lithium ion battery. Results demonstrate that the as-synthesized CoMn2O4 materials exhibit excellent electrochemical properties. The CoMn2O4 anode can deliver a large capacity of 1070 mAh g-1 in the first discharge, a reversible capacity of 500 mAh g-1 after 100 cycles with a coulombic efficiency of 98.5% at a charge-discharge current density of 200 mA g-1, and a specific capacity of 385 mAh g-1 at a much higher charge-discharge current density of 1600 mA g-1. Synchrotron X-ray absorption fine structure (XAFS) techniques were applied to investigate the conversion reaction mechanism of the CoMn2O4 anode. The X-ray absorption near edge structure (XANES) spectra revealed that, in the first discharge-charge cycle, Co and Mn in CoMn2O4 were reduced to metallic Co and Mn when the electrode was discharged to 0.01 V, while they were oxidized respectively to CoO and MnO when the electrode was charged to 3.0 V. Experiments of both XANES and extended X-ray absorption fine structure (EXAFS) revealed that neither valence evolution nor phase transition of the porous core-shell CoMn2O4 microspheres could happen in the discharge plateau from 0.8 to 0.6 V, which demonstrates the formation of solid electrolyte interface (SEI) on the anode.

MnO2 nanowires-decorated carbon fiber cloth as electrodes for aqueous asymmetric supercapacitor

Manganese dioxide nanowires (MnO2 NWs) anchored on carbon fiber cloth (CFC) were fabricated through a simple hydrothermal reaction and used as integrated electrodes for supercapacitor. The morphology-dependent electrochemical performance of MnO2 NWs was confirmed, yielding good capacitance performance with a high specific capacitance of 3.88[Formula: see text][Formula: see text] at a charge–discharge current density of 5[Formula: see text][Formula: see text] and excellent stability of 91.5% capacitance retention after 3000 cycles. Moreover, the composite electrodes were used to fabricate supercapacitors, which showed a high specific capacitance of 194[Formula: see text][Formula: see text] at a charge–discharge current density of 2[Formula: see text][Formula: see text] and high energy density of 0.108[Formula: see text][Formula: see text] at power density of 2[Formula: see text][Formula: see text], foreboding its potential application for high-performance supercapacitor.

NiCo2S4 nanotube arrays grown on flexible carbon fibers as battery-type electrodes for asymmetric supercapacitors

NiCo2S4 nanotube arrays grown on carbon cloth are prepared successfully by a facile two-step method. The as-prepared tubular nanoarchitecture deliver a high specific capacity of 578 C/g at a galvanostatic charge-discharge current density of 0.5 A/g with good cycling stability in 3 M KOH aqueous solution. Furthermore, the all-solid-state asymmetric supercapacitor based NiCo2S4 nanotube arrays as the positive electrode shows a superior energy density of 24.78 Wh/kg at a power density of 1770.13 W/kg. The results reveal that the as-synthesized NiCo2S4 nanotube arrays might be promising electrode materials for electrochemical energy storage.

Insights into all-vanadium redox flow battery: A case study on components and operational conditions

This works reports the effect of operation conditions on the performance of a 25 cm2 vanadium redox flow cell (VRFC) featuring commercial carbon felt (CF) as electrode and different commercial membranes, namely electrolyte flow rate and charge-discharge current density. The effect of electrode compression and thermal treatment was also assessed.The battery performance was evaluated based on the charge-discharge curves and average efficiencies during 20 charge-discharge cycles; the capacity fading was evaluated after 20 cycles. The limiting current was obtained through polarization curves and the ohmic resistance of the battery was obtained by electrochemical impedance spectroscopy (EIS).The electrodes yielding the highest energy efficiency (EE), ca. 85%, at 40 mA cm−2 current density were thermally treated at 390 °C or 415 °C during 12 h under air. This result represents an improvement of more than 50% compared with the as-received electrodes. Additionally, energy efficiency increased ca. 10% when electrode compression rose from 8% to 25%. Increasing the flow rate from 37.5 cm3 min−1 to 150 cm3 min−1 EE was also enhanced from 76% to 84% at 40 mA cm−2. The type of membrane affects the performance: a comparison between a commercial anion exchange membrane (AEM) and Nafion® series cation exchange membranes (CEM) showed that AEM, generally, yields higher EE than all Nafion® membranes tested; however, the capacity fading of AEM is much higher than CEM.The information provided in this work shows that, by tuning operational conditions and using suitable components, it is possible to increase the performance of a VRFC without additional costs.

High-performance aqueous rechargeable sulfate- and sodium-ion battery based on polypyrrole-MWCNT core-shell nanowires and Na0.44MnO2 nanorods

Aqueous rechargeable sodium-ion batteries (ARSBs) have the potential for application in large-scale electric energy storage systems owing to the safety of the non-flammable aqueous electrolyte and the natural abundance of sodium resources. Herein, we demonstrate the high performance of an aqueous rechargeable sulfate- and sodium-ion battery based on a MWCNT-polypyrrole core–shell nanowire anode and a Na0.44MnO2 nanorod cathode in a 1 M aqueous Na2SO4 electrolyte. Because the charge-discharge process involves the simultaneous uptake and release of both sulfate anions and sodium cations, it offers a wider choice of electrode materials for use at high voltages. The MWCNT-polypyrrole core-shell nanowire//Na0.44MnO2 nanorod full cell delivered excellent discharge capacities of 99.2 mA h g−1 and 87.2 mA h g−1 with a high voltage of 1.6 V at the charge-discharge current densities of 100 mA g−1 and 3000 mA g−1, respectively. When compared with previous ARSBs, the aqueous rechargeable sulfate- and sodium-ion battery shows much better performance at relatively high charge–discharge rates, making it suitable for large-scale energy storage applications.

Novel corn cob-like Fe3O4@Ni3S2 as high-performance electrode for supercapacitors

Corn cob-like Fe3O4@Ni3S2 nanocomposites was synthesized through a facile two-step hydrothermal process. The precursor was obtained by a facile calcination of a Fe-MOF template, then, nickel sulfide coated on iron oxide composites were synthesized using a hydrothermal method. In addition, the fabricated Fe3O4@Ni3S2 electrode revealed a great electrical performances with a maximum specific capacitance of 1200[Formula: see text]F[Formula: see text]g[Formula: see text] at 1[Formula: see text]A[Formula: see text]g[Formula: see text], a capacitance retention of 83% could be observed after 1000 cycles at a great charge–discharge current density of 5[Formula: see text]A[Formula: see text]g[Formula: see text]. We believed that the excellent performance might be ascribed to the synergistic effect between the Fe3O4and Ni3S2. Thus, the results demonstrate the corn cob-like Fe3O4@Ni3S2 composite is prominent candidate in the field of supercapacitor applications.

Effect of Deposition Parameters on the Morphology and Electrochemical Behavior of Lead Dioxide

Lead dioxide thin films were electrodeposited on nickel substrate from acidic lead nitrate solution. Current efficiency and thickness measurements, cyclic voltammetry, AFM, SEM, and X-ray diffraction experiments were conducted on PbO2 surface to elucidate the effect of lead nitrate concentration, current density, temperature on the morphology, chemical behavior, and crystal structure. Experimental results showed that deposition efficiency was affected by the current density and solution concentration. The film thickness was independent of current density when deposition from high Pb(NO3)2 concentration, while it decreased for low concentration and high current density deposition. On the other hand, deposition temperature had negative effect on current efficiency more for lower current density deposition. Cyclic voltammetric study revealed that comparatively more β-PbO2 produced compact deposits when deposition was carried out from high Pb(NO3)2 concentration. Such compact films gave lower charge discharge current density during cycling. SEM and AFM studies showed that deposition of regular-size sharp-edge grains occurred for all deposition conditions. The grain size for high temperature and low concentration Pb(NO3)2 deposition was bigger than from low temperature and high concentration deposition conditions. While cycling converted all grains into loosely adhered flappy deposit with numerous pores. X-ray diffraction measurement indicates that high concentration, high temperature, and high current density favored β-PbO2 deposition while α-PbO2 converted to β-PbO2 together with some unconverted PbSO4 during cycling in H2SO4. Keywords: Lead dioxide, Electrodeposition, Current efficiency, Charge-discharge density, Charge efficiency