In this work we have investigated the charge storage mechanism of MnO2 electrodes in ionic liquid electrolytes. We show that by using an ionic liquid with a cation that has the ability to form hydrogen bonds with the active material (MnO2) on the surface of the electrode, a clear faradaic contribution is obtained. This situation is found for ionic liquids with cations that have a low pKa, i.e. protic

Molten carbonate direct carbon fuel cells (MC-DCFCs) are one of the most promising technologies for clean and efficient energy conversion from solid carbon. However, the low power density of carbon fuel cells has been one of the challenging bottlenecks limiting their application. In this study, a novel anode structure is designed and fabricated for an MC-DCFC to improve the mixing uniformity between

In this study, electrolyte-supported (Cell A) and anode-supported (Cell B) micro-tubular solid oxide fuel cells (SOFCs) based on the La9.8Si5.7Mg0.3O26±δ (LSMO) electrolyte is built through an extrusion and dip-coating processes. The formulations and process conditions for these cells are established and optimized. Both cell configurations show no visible delamination or cracking, and reaction zones

For a lithium battery, a gated recurrent unit recurrent neural network (GRU-RNN) based momentum gradient method is investigated to estimate its state of charge (SOC). In the momentum gradient method, the current weight change direction takes a compromise of the gradient direction at current instant and at historical time to prevent the oscillation of the weight change and to improve the SOC estimation

Retired lithium-ion batteries from electric vehicles provide considerable social, economic and environmental benefits in second-use applications especially for energy storage. However, the effective capacity estimation is a key technique and difficulty for second-life of large-scale retired cells. To address the issue, this paper provides a fast novel capacity estimation method from a new perspective

In practical applications, the batteries are usually subjecting to short-term high-temperature storage (e.g., 80 °C for several days), which is quite different from long-term storage with temperature lower than 60 °C. Herein, the effect of such a short-term high-temperature storage on the performance of LiNi0.5Co0.2Mn0.3O2/graphite battery under normal cycling (under 1C at 25 °C) is studied by electrochemical

Industrial water electrolyzers apply direct current in kiloampere ranges. Therefore, rectifiers are typically based on thyristors despite the high amplitude current fluctuation excited by the rectifier. This paper studies the effect of thyristor rectifiers on the power quality of the electrolyzer stack and the supplying AC grid. The thyristor bridge excites high current and power fluctuation causing

In this work, abundant oxygen vacancies are introduced into NdBaCo2O5+δ (NBCO) by partial substitution of cobalt to facilitate the electrochemical activity of ORR. The oxygen vacancy concentration of NdBaCo1.8Sc0.2O5+δ (NBCSc-2) is more than twice as that of NdBaCo2O5+δ. The increased oxygen surface exchange, bulk diffusion coefficients and adequate conductivity for NBCSc-2 can be responsible for the

A triple junction (3J) solar cell having 33% efficiency at one Sun condition is integrated with an electrolyzer containing Pt wire electrodes to study the effect of pH, temperature and low flux solar light on H2 production from water. Results indicate that electrolyte conduction affects the rate of reaction mostly due to the large voltage at maximum power (Vmpp) of the PV-cell. Measurements are performed

Sulfur dioxide is a common air pollutant that has an adverse impact on proton exchange membrane fuel cells (PEMFCs). The present study reports the spatial performance and degradation of low-Pt PEMFCs exposed to trace concentrations of SO2 in a cathode feed stream. PEMFCs exposed to 2 ppm SO2 resulted in a performance loss of 240 and 345 mV for constant current holds of 0.2 and 0.8 A cm−2. However,

Layer-structured transition-metal disulfides are considered as promising anode materials for sodium ion batteries (SIBs). However, large volume change over charge-discharge cycles is behind a major problem for mechanical failure, leading to low capacity, poor rate and cycling performance. In this work, we devise a one-step solvothermal method to construct reduced graphene oxide (RGO) aerogel containing

Cheap, high-rate and long-life batteries are urgently needed for grid-scale storage of renewable energy. Rechargeable zinc (Zn) batteries are potential candidates due to the high volumetric energy density and low cost of Zn anode. However, conventional Zn batteries employing metal oxide cathodes usually suffer from poor rate capabilities caused by the high migration barrier of Zn2+ in the metal oxide

Reactant distribution and water management are critically important to the performance of proton exchange membrane fuel cell (PEMFC). The application of baffle plate is an effective way to improve reactant transport and water removal in the porous electrode of PEMFC. In this study, a three-dimensional multiphase PEMFC model is developed with Forchheimer's inertial effect in the porous electrode to

Here we report selective separation of high-purity H2 from a mixture of 50%H2-50%N2 at reduced temperatures using novel ceramic hydrogen pumps that feature thin dense BaZr0·1Ce0·7Y0·2O3−δ (BZCY) electrolytes symmetrically sandwiched between two identical NiO-BZCY electrodes. Scanning electron microscopy observations show nanoporous nickel catalysts in the cermets as produced from in situ slow reduction

The lithiation of silicon (Si) involves the evolution of reaction front, self-limiting lithiation, and visco-plastic deformation. During the lithiation of crystalline Si, solid-state amorphization occurs to lower Gibbs free energy, and lithiated Si-electrode in lithium-ion battery is mainly present in amorphous phase. In this work, we develop a viscoplastic constitutive relationship for the lithiation-induced

A two-dimensional multi-physical model was applied for analyzing the performance of a vanadium redox flow battery under variable operating strategies. The study indicated that for constant flow rate and current, it is inconsistent to give consideration to both the capacity and efficiency of the battery. In contrast, variable flow rate strategy can enhance the overall battery performance. Considering

Fuel cell technologies are applied to the propulsion systems on aircraft to save fuel and reduce emissions. A novel hybrid engine with low specific fuel consumption by integrating solid oxide fuel cells and turbine engines is proposed in our previous papers. However, the real performance potential of the engine and the interrelation among the components have not illustrated. To demonstrate the irreversibility

There is a growing interest in the development of high energy on-chip capacitive energy storage units for application in microelectronic devices. Lithium-ion capacitor (LIC) typically comprising battery-type and capacitor-type electrodes offer the opportunity for an improved energy density in capacitive energy storage. In this work, an aqueous on-chip LIC was fabricated using carbon microelectromechanical

Electromechanical structural integrity and thermal stability dictate the safety performance of lithium-ion batteries. Progressive deformation and failure across microscopic and macroscopic lengths scales that are responsible for internal short circuit (ISC) in lithium-ion cells under mechanical abuse conditions remains elusive. In this study, a series of indentation tests were conducted on lithium-ion