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A precise interpretation of lithium-ion battery (LIB) heat generation is indispensable to the advancement and accomplishment of thermal management systems for different applications of LIB, including electric vehicles. The internal resistance of a lithium titanate oxide (LTO)-based LIB was determined at different state of charge (SOC) levels and current rates to understand the relationship between internal resistance and heat generation. Random and different pulse discharge current step durations were applied to consider the effect of different SOC interval levels on heat generation. The total generated heat was measured for different discharge rates and operating temperatures in a Netzsch IBC 284 calorimeter. It was seen that a 6.7% SOC decrease at high SOC levels corresponds to 0.377 Wh, 0.728 Wh, and 1.002 Wh heat generation for 26A, 52A, and 78A step discharge, both at 20 °C and 30 °C. However, a 1.85% SOC decrease at medium SOC levels corresponds already to 0.57 Wh, 0.76 Wh, and 0.62 Wh heat generation. It can be inferred that the impact of SOC level on heat generation for this cell is more prominent at a lower than at a higher SOC.

Power-to-methanol is seen as a key energy storage technology in contributing to reach climate targets and unleash the great potential for renewable electricity. This study conducted dynamic simulations that focuses on the feed gas composition effects and surrogate modeling by using the nonlinear autoregressive exogenous (NARX) model for the green methanol production. The modeling results showed obvious influences of feed gas composition on the process efficiency and CO2 conversion, which were predicted by the NARX model with promising accuracy.

This study investigates the effects of operatingparameters of different current density, temperature and pressure onthe performance of a proton exchange membrane (PEM) waterelectrolysis stack. A 7-cell PEM water electrolysis stack wasassembled and tested under different operation modules. The voltagechange and polarization curves under different test conditions, namelycurrent density, temperature and pressure, were recorded. Resultsshow that higher temperature has positive effect on overall stackperformance, where temperature of 80 ℃ improved the cellperformance greatly. However, the cathode pressure and currentdensity has little effect on stack performance.

De globale klimaudfordringer kræver, at vi alle tager et fælles ansvar, og at kommuner, uddannelsesinstitutioner, erhverv og borgere arbejder sammen på tværs for at opfylde de ambitiøse klimamål.I de kommende år vil der være fokus på en grøn omstilling af vores samfund, og her spiller især kommunerne og energi- og forsyningssektoren en afgørende rolle.I Aalborg Kommune har vi siden begyndelsen af 1990’-erne arbejdet med at nedbringe udledningen af drivhusgasser fra energiforsyningen og transport. Vi har gennem de seneste 10 år arbejdet målrettet med langsigtet og strategisk energi- og varmeplanlægning for at opnå Aalborg Kommunes overordnede mål om at være fossilfri senest i 2050.Vi har løbende arbejdet på at fremme den grønne omstilling, hvilket blev understreget af Aalborg Kommunes køb af Nordjyllandsværket og deraf følgende fokus på at få udfaset brugen af kul.De nye politiske målsætninger, den teknologiske udvikling på energiområdet og købet af Nordjyllandsværket har medført behov for at opdatere Aalborg Kommunes visioner og strategier på energiområdet.Formålet er at få et helhedsorienteret grundlag for de langsigtede beslutninger, der skal træffes i Aalborg Kommune, blandt andet for at opfylde lokale, nationale og internationale klima- og energimålsætninger.Derfor har Aalborg Kommune nu - sammen med Aalborg Universitet – udarbejdet Energivision for Aalborg Kommune 2050 - Smart Energy Aalborg. Energivisionen omfatter det samlede energiforbrug og tager udgangspunkt i, at vi vil være uafhængige af fossile brændsler og basere os på lokale vedvarende energikilder.Energivision 2050 viser, at et samlet energisystem med 100 pct. vedvarende energi senest i 2050 er muligt. Det kræver dog, at vi får skabt et sammenhængende integreret energisystem, hvor de forskellige teknologierarbejder sammen på tværs af forsyningsarter.

In this corrigendum, the authors would like to make a correction in the Section of Experimental, Single cell assembly, the second sentence: “The components of the MEA from anode to cathode are Ti felt (350 mm thick, porosity of 81%, fiber diameter of 20 mm) that was employed as the anode porous transport layer” should be corrected to “The components of the MEA from anode to cathode are Ti felt (350 μm thick, porosity of 81%, fiber diameter of 20 μm) that was employed as the anode porous transport layer”. The authors would like to apologise for any inconvenience caused.

Cooling of the lithium-Ion batteries is an important issue in electric vehicles industries. This paper introduces a simple analytical solution for the battery cooling by considering different parameters that affect the air and liquid cooling of lithium-Ion batteries. It was assumed that the cell dimension is 204mm*129mm.

Lithium-ion batteries are indispensable parts in electric vehicles, owing to their high energy density, discharge and charge efficiency. Therefore, it is essential to investigate their charging and discharging behavior at different current rates. The purpose of this investigation was to determine and analyses the discharge and charge behavior of a lithium-ion battery at different conditions. In addition, the relationship between cycle number, current and capacity during discharging and charging were analyzed. It was concluded that the extracted charge declined nonlinearly with the amount of the discharging current.

Lithium-ion batteries have many advantages in compare to other conventional batteries. Because of that, they have many applications in different sectors such as portable electronic devices, electric vehicles and other fields. To assure that the operation and performance of lithium-ion batteries are reliable, safe and economic, the approximation of state of charge, cycle life and other parameters for lithium-ion batteries are necessary. Equivalent circuit models are an important tool in the field of research in lithium-ion batteries. Several researcher have suggested a variety of equivalent circuit models. Some of these models are simple whereas some others are complicated. This paper presents a review of different equivalent circuit models and parameters identification methods in lithium-ion batteries for energy storage applications. These models include the internal resistance model, one time constant model, two time constants model, Thévenin model, PNGV (partnership for a new generation of vehicles) model, DP (dual polarization) model, improved PNGV model, tree seeds algorithm, electrochemical impedance spectroscopy method, and Randles’ model.

A single polymer electrolyte membrane (PEM) water electrolyzer cell is operated under cathode no flow, co flow and counter flow water recirculation configurations in this work. The polarization curve, electrochemical impedance spectrum (EIS) and current and temperature distribution of the PEM water electrolyzer cell are measured under different water recirculation configurations and different applied current. The experimental results show that the counter flow configuration brings about slightly better cell performance and lower polarization resistance. The current and temperature distribution pattern are similar under different water recirculation configurations and different applied current. However, the current and temperature distribution is more uniform under counter flow water recirculation, which could be related with smaller different between inlet and outlet water temperature under counter flow configuration.

In this study, a small PEM water electrolysis single cell set up is utilized to extract information about degradation mechanisms. The major parameter of interest is the operational condition, which is changed from constant to cycling current input signal throughout a period of just over 1000h. The cell shows a high reversible share of the voltage increase at constant operation, which builds up slowly and can be recovered through a short interruption of cell operation. Impedance measurements reveal a considerable change in ohmic contributions as well as electrochemical performance over time. The model supported IV curve analysis backs the impedance data and reveals an increase in contact resistances. At the same time, the electrochemical surface area on both electrodes is reduced. The results suggest that dynamic operation may be beneficial for cell performance and therefore operational cost, while a degradation rate of 164.1µV*h−1 was calculated.

The water balance of a proton exchange membrane fuel cell (PEMFC) can provide valuable insight into the state of the fuel cell. The most commonly applied method to measure the water balance is the knock-out method where the flaw gas of anode and/or cathode is cooled down and the condensed amount of water is weighed and compared to the amount of product water, while over the past years our group has developed a new method by applying hot wire anemometry at the anode outlet. In this work, a comparison between the knock-out and hot wire methods is experimentally demonstrated for 3.8 kW water-cooled PEMFC stack. The stack is run under wet conditions at different current densities and stoichiometric ratios. The hot-wire method has shown a higher sensitivity and an instant response for the measured water balance. Meanwhile, the knock-out method showed less sensitivity, much slower time response, and higher inaccuracies.