This paper reports the use of the electrospinning technique for the synthesis of nanocomposite micro/nanofibers by combining a polymeric precursor with hydrophobic behavior like polyvinyl chloride (PVC) with nanoparticles of a corrosion inhibitor like ZnO. These electrospun fibers were deposited on substrates of the aluminum alloy 6061T6 until forming a coating around 100 μm. The effect of varying the different electrospinning deposition parameters (mostly applied voltage and flow-rate) was exhaustively analyzed in order to optimize the coating properties. Several microscopy and analysis techniques have been employed, including optical microscopy (OM), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Water contact angle (WCA) measurements have been carried out in order to corroborate the coating hydrophobicity. Finally, their corrosion behavior has been evaluated by electrochemical tests (Tafel curves and pitting potential measurements), showing a relevant improvement in the resultant corrosion resistance of the coated aluminum alloys.

In this work, polymeric fibers of polystyrene (PS) with incorporated ZnO nanoparticles have been deposited onto an aluminum alloy substrate (6061T6) by using the electrospinning technique. In order to optimize the deposition process, the applied voltage and flow rate have been evaluated in order to obtain micrometric electrospun fibers with a high average roughness and superhydrophobic behavior. Thermogravimetric analysis (TGA) has also been employed in order to corroborate the amount of ZnO incorporated into the electrospun fibers, whereas differential scanning calorimetry (DSC) has been performed in order to determine the glass transition temperature (T g ) of the polymeric electrospun fibers. In addition, a specific thermal treatment (T g + 20 • C) of the synthesized electrospun fibers has been evaluated in the resultant corrosion resistance. A comparative study with previously reported results corresponding to polyvinyl chloride (PVC) fibers is carried out along this paper to show the changes in behavior due to the different compositions and fiber diameters. The coating has produced an important reduction of the corrosion current of the aluminum substrate in two orders of magnitude, showing also an important enhancement against pitting corrosion resistance. Finally, this deposition technique can be used as an innovative way for the design of both superhydrophobic and anticorrosive surfaces in one unique step over metallic substrates with arbitrary geometry.

In this paper a dynamic model for the simulation of pressurized alkaline water electrolyzers is presented. The model has been developed following a multiphysics approach, integrating electrochemical, thermodynamic, heat transfer and gas evolution processes in order to faithfully reproduce the complete dynamical behavior of these systems. The model has been implemented on MATLAB/Simulink and validated through experimental data from a 1 Nm 3 h -1 commercial alkaline water electrolyzer, and the simulated results have been found to be consistent with the real measured values. This model has a great potential to predict the behavior of alkaline water electrolyzers coupled with renewable energy sources, making it a very useful tool for designing efficient green hydrogen production systems.

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This contribution presents a methodology for the integration of Li-ion batteries discarded from electric vehicle into a collective self-consumption installation, showing the technical feasibility of such battery second use. In this regard, the state of charge (SOC) estimation is a relevant issue for the energy management of the second-life battery. Therefore, a SOC estimator is proposed in this contribution and tested in field. Moreover, the revealed costs analysis allows an economic comparison between the integration of a discarded battery pack in a second-life application or a remanufacture of these packs, thereby selecting the most suitable cells to build second-life batteries. This is a crucial issue for companies focused on the development of second-life batteries. The results obtained after testing the second-life battery pack in a real installation make it possible to extol the benefits of including this type of batteries in a self-consumption system, reaching a self-consumption ratio of 69 % and reducing by 36 % the maximum power peak demanded from the grid.

In this work, the electrospinning technique is used for the synthesis of micro/nanofibers using a polymeric precursor with hydrophobic (even superhydrophobic) behaviour such as polystyrene (PS). These electrospun fibers are deposited onto aluminum substrates (6061T6). The effect of varying the different electrospinning deposition parameters (mostly applied voltage and flowrate) will be exhaustively analyzed in order to optimize the resultant electrospun coatings. Several fiber characterization tests have been performed, including Field Emission Scanning Electron Microscopy (FE-SEM), Atomic Force Microscopy (AFM), Termogravimetric analysis (TGA), Optical Microscopy (OM) and Water Contact Angle (WCA) measurements. Furthermore, the anticorrosion properties of these electrospun coatings can be enhanced by the addition of metal oxide nanoparticles (ZnO) which act as corrosion inhibitors. Finally, electrochemical corrosion tests (Tafel and pitting tests) have been perfomed, showing an improvement in the resultant corrosion resistance of the aluminum alloys coated by the combination of both polymeric film with metal oxide inorganic nanoparticles.

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