scholarly journals Numerical Modeling and Analysis of the Performance of an Aluminum-Air Battery with Alkaline Electrolyte

Processes ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 658
Author(s):  
Jiadong Xie ◽  
Pan He ◽  
Ruijie Zhao ◽  
Jianhong Yang

A numerical model is created to simulate the discharge performance of aluminum-air batteries (AABs) with alkaline electrolyte. The discharge voltage and power density, as a function of the discharge current density, are predicted for the modeled AAB and compared with experimental measurements. A good agreement between model and experiment is found. The effect of various model parameters on the battery performance is studied by adjusting the parameters within a suitable range. The results show that electrolyte thickness is a key factor that can strongly increase the power density and the corresponding current density as the electrolyte thickness decreases. The peak of power density is increased by a factor of two if the electrolyte thickness is reduced from 7 mm to 3 mm. The alkaline concentration is also an important factor, since both the voltage and power density curves are significantly raised as the NaOH concentration is increased from 1 to 4 mol/L. The partial oxygen pressure plays a secondary role in performance improvement. The peak of power density is increased by 35% using pure oxygen in the air electrode. In addition, the active specific surface area of the catalyst layer also affects the discharge capability of the AAB system.

2010 ◽  
Vol 177 ◽  
pp. 407-410
Author(s):  
Xi Bao Li ◽  
Jian Wang ◽  
Xiao Hua Yu ◽  
Hong Xing Gu ◽  
Gang Qin Shao

NiO-YSZ (NiO-yttria stabilized zirconia, 3:2, wt.%) and samaria doped ceria (SDC) tapes were prepared by aqueous tape casting. NiO-YSZ anode-supported SDC film electrolyte half-cell was fabricated by laminating and co-sintering at 1400°C for 2 h. The single cell was prepared after LSCF-SDC (lanthanum strontium cobalt ferrite-SDC, 1:1, wt.%) cathode was coated on the electrolyte surface and sintered at 1300 °C for 2 h. The discharge performance of the single cell was tested from 500 °C to 800 °C at different H2 flow rate. Results showed that the relationship between current (I) of and H2 flow rate (ν) was I = 8 × 106 ν. Before reaching the threshold value of H2 flow rate, the current density of single cell increased with the increasing of H2 flow rate. However, the current density did not change with increasing of H2 flow rate over the threshold value. The open circuit voltage (OCV) of single cell at 500°C, 600°C, 700°C, 800°C was 0.978, 0.921, 0.861, 0.803 V, respectively. The maximum power density reached 93.03 mW/cm2 at 800°C. The resistance of interface layer between Ni-YSZ anode and SDC electrolyte was the key impact on the power density.


Author(s):  
Utku Gulan ◽  
Hasmet Turkoglu ◽  
Irfan Ar

In this study, the fluid flow and cell performance in cathode side of a proton exchange membrane (PEM) fuel cell were numerically analyzed. The problem domain consists of cathode gas channel, cathode gas diffusion layer, and cathode catalyst layer. The equations governing the motion of air, concentration of oxygen, and electrochemical reactions were numerically solved. A computer program was developed based on control volume method and SIMPLE algorithm. The mathematical model and program developed were tested by comparing the results of numerical simulations with the results from literature. Simulations were performed for different values of inlet Reynolds number and inlet oxygen mole fraction at different operation temperatures. Using the results of these simulations, the effects of these parameters on the flow, oxygen concentration distribution, current density and power density were analyzed. The simulations showed that the oxygen concentration in the catalyst layer increases with increasing Reynolds number and hence the current density and power density of the PEM fuel cell also increases. Analysis of the data obtained from simulations also shows that current density and power density of the PEM fuel cell increases with increasing operation temperature. It is also observed that increasing the inlet oxygen mole fraction increases the current density and power density.


2013 ◽  
Vol 10 (2) ◽  
pp. 462-471
Author(s):  
Baghdad Science Journal

In this work the design and construction of optical pumping system was presented. The parameters of the pumping source to obtain discharge current density sufficient to shift the flash lamp spectrum towards uv portion of spectrum were measured.The current density was supplied to the flash lamp must be greater than 4000Amp./cm2 to obtain the spectral range wavelength lies between 0.2 and 0.35?m. The current density was obtained by a capacitor 50?F, at 7KV discharge voltage. The applied electrical energy to the flash lamp was more than 1200 J, and the current density was around 5000 Amp./cm2.The electrical parameters of the flash lamp were calculated. The impedance parameters(K0) from the voltage and the peak current pulse was measured in range equal to 57, while the damping factor(?) was 1.3. The energy of the flash lamp was around 75% from the input electrical energy. The external trigger circuit was limited the increase the applied voltage, which is responsible for the damping factor.


2012 ◽  
Vol 519 ◽  
pp. 160-163 ◽  
Author(s):  
Fang Wang ◽  
Da Liang Xu ◽  
Chun Sheng Liang ◽  
Hong Yuan Sun ◽  
Zhong Kuan Luo

Lithium–oxygen coin cells without catalyst were assembled in argon atmosphere and tested in pure oxygen. Results showed that the first discharge performance of the batteries was strongly affected by the carbon loading, electrolyte amount and current density. At the carbon loading (0.4 mg/cm2), the electrolyte amount (160 μL/cell) and the current density (0.05 mA/cm2), a high capacity of 4586.5 mAh/g was obtained. The capacity decreased when the carbon loading or current density was increased. And the capacity would have a decrease when the amount of electrolyte was decreased. The highest capacity of 6010.2 mAh/g was obtained by optimizing the combination of carbon loading and electrolyte amount at current density of 0.01mA/cm2. However, the discharge capacity sharply decreased from the second cycle. It may be partly due to the fact that the pores of cathode surface were blocked by discharge products at the end of discharge.


2020 ◽  
Vol 44 (5) ◽  
pp. 1227-1243
Author(s):  
Hande UNGAN ◽  
Ayşe BAYRAKÇEKEN YURTCAN

Water management is one of the obstacles in the development and commercialization of proton exchange membrane fuel cells (PEMFCs). Sufficient humidification of the membrane directly affects the PEM fuel cell performance. Therefore, 2 different hydrophobic polymers, polydimethylsiloxane (PDMS) and (3-Aminopropyl) triethoxysilane (APTES), were tested at different percentages (5, 10, and 20 wt.%) in the catalyst layer. The solution was loaded onto the surface of a 25 BC gas diffusion layer (GDL) via the spraying method. The performance of the obtained fuel cells was compared with the performance of the commercial catalyst. Characterizations of each surface, including different amounts of PDMS and APTES, were performed via scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analyses. Molecular bond characterization was examined via Fourier transform infrared spectroscopy (FTIR) analysis and surface hydrophobicity was measured via contact angle measurements. The performance of the fuel cells was evaluated at the PEM fuel cell test station and the 2 hydrophobic polymers were compared. Surfaces containing APTES were found to be more hydrophobic. Fuel cells with PDMS performed better when compared to those with APTES. Fuel cells with 5wt.% APTES with a current density of 321.31 mA/cm2and power density of 0.191 W/cm2, and 10wt.% PDMS with a current density of 344.52 mA/cm2and power density of 0.205 W/cm2 were the best performing fuel cells at 0.6V.


Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 931
Author(s):  
Cristina Reche ◽  
Carmen Rosselló ◽  
Mónica M. Umaña ◽  
Valeria Eim ◽  
Susana Simal

Valorization of an artichoke by-product, rich in bioactive compounds, by ultrasound-assisted extraction, is proposed. The extraction yield curves of total phenolic content (TPC) and chlorogenic acid content (CAC) in 20% ethanol (v/v) with agitation (100 rpm) and ultrasound (200 and 335 W/L) were determined at 25, 40, and 60 °C. A mathematical model considering simultaneous diffusion and convection is proposed to simulate the extraction curves and to quantify both temperature and ultrasound power density effects in terms of the model parameters variation. The effective diffusion coefficient exhibited temperature dependence (72% increase for TPC from 25 °C to 60 °C), whereas the external mass transfer coefficient and the equilibrium extraction yield depended on both temperature (72% and 90% increases for TPC from 25 to 60 °C) and ultrasound power density (26 and 51% increases for TPC from 0 (agitation) to 335 W/L). The model allowed the accurate curves simulation, the average mean relative error being 5.3 ± 2.6%. Thus, the need of considering two resistances in series to satisfactorily simulate the extraction yield curves could be related to the diffusion of the bioactive compound from inside the vegetable cells toward the intercellular volume and from there, to the liquid phase.


1995 ◽  
Vol 18 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Sui-Yang Huang ◽  
Ladislav Kavan ◽  
Andreas Kay ◽  
Michael Grätzel ◽  
Ivan Exnar

Nanocrystalline TiO2films were explored for the first time as electrode material for a rechargeable lithium intercalation cell, i.e., Li/LiCF3SO3+ PC/TiO2. Two kinds of nanocrystalline films, TiO2F387 (Degussa) and TiO2colloid-240, were investigated. These films exhibited excellent performance renderings them a promising choice for secondary battery applications. At a current density of 0.01 mA/cm2, two voltage plateaus at 1.78 and 1.89 V were observed for TiO2F387 films during charge and discharge, respectively. The TiO2electrode charge capacity per unit weight rose with decreasing current density. The highest capacity, obtained at a current density of 0.005 mA/cm2and a final discharge voltage of 1.4 V, was 265 mAh/g corresponding to a lithium insertion ratio ofx= 0.8. Nanocrystalline TiO2colloid-240 films showed a similar performance. The cycle life of a TiO2colloid-240 cell at a high current density was found to be excellent; a capacity loss lower than 14% has been observed over 100 charge/discharge cycles.


Author(s):  
Feng Zhou ◽  
Jianxin (Roger) Jiao

Traditional user experience (UX) models are mostly qualitative in terms of its measurement and structure. This paper proposes a quantitative UX model based on cumulative prospect theory. It takes a decision making perspective between two alternative design profiles. However, affective elements are well-known to have influence on human decision making, the prevailing computational models for analyzing and simulating human perception on UX are mainly cognition-based models. In order to incorporate both affective and cognitive factors in the decision making process, we manipulate the parameters involved in the cumulative prospect model to show the affective influence. Specifically, three different affective states are induced to shape the model parameters. A hierarchical Bayesian model with a technique called Markov chain Monte Carlo is used to estimate the parameters. A case study of aircraft cabin interior design is illustrated to show the proposed methodology.


2012 ◽  
Vol 576 ◽  
pp. 484-487
Author(s):  
Raihan Othman ◽  
Farouq Ahmat ◽  
Muhd Amlie Ibrahim ◽  
Assayidatul Laila Nor Hairin ◽  
Hanafi Ani Mohd

Zinc anode is electrodeposited from a 2-M zinc chloride electrolytic bath with varying ammonium chloride supporting electrolyte concentrations (0-5 M) and plating current density (0.1 – 0.6 A cm-2). The total charge quantity supplied during electrodeposition is fixed at 150 mAh. Alkaline zinc-air cell is fabricated using the electrodeposited zinc anode and characterized according to its discharge capacity at constant load current of 20 mA. The effect of various qualities of zinc electrodeposits on the cell discharge performance is discussed. It is found that zinc electrodeposits prepared from electrolytic bath of 5-M ammonium chloride and 0.5 A cm-2 plating current density produced zinc-air cell with the highest output energy i.e. 24 mWh. We observe that the influence of plating current density is more prominent than the plating bath formulation on the zinc anode performance in the cell.


Sign in / Sign up

Export Citation Format

Share Document