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Li-ion cells are one of the core components for the actual and future electric mobility. Differently from other types of applications and due to the high charge/discharge rates, the thermal-related issues in batteries for mobility are drastically relevant and can affect the reliability, the safety and the performance of the system. Indeed, limited temperature differences within a battery pack have a significant impact on its efficiency, thus it is important to predict and control the cell and battery pack temperature distribution. In the proposed study, a CFD analysis has been carried out to quantify the temperature and heat distribution on a single li-ion pouch cell. The main objective of this work is to determine the temperature imbalance on the cell and the required cooling load in order to be able to correctly design the cooling system and the best module architecture. The internal heat generation occurs as a result of electrochemical reactions taking place during charge and discharge of batteries. An electric model of the cell allows to assess the thermal power generation; the model parameters are changed according to the operative conditions to improve the accuracy, specifically to take into account varying temperature conditions and C-rates. The high accuracy of the model with respect to experimental data shows the potentiality of the proposed approach to support the optimization of Li-ion modules cooling systems and architecture design.

Small-scale hybrid energy systems are often composed by different power production technologies and adopted in mini-grids. In this work, a Mixed Integer Linear Programming optimization algorithm has been developed to compute the optimal scheduling of a micro-grid constituted by Internal Combustion Generators (ICGs) and a Storage System that can be either a conventional battery storage system or a Pumping Hydro energy Storage (PHES) based on Pump-as-Turbines. The algorithm computes the optimal energy generation scheduling of the micro-grid, minimizing a multi-objective fitness function constituted by the total costs of the energy system and the total CO2 and NOx emissions. In particular, the emissions are modelled with varying trends depending on the ICG load and not with constant values, which represents a simplification that is often adopted but that can induce misleading results. Furthermore, the algorithm takes into account all the physical constraints related to the generators and the storage system, such as maximum and minimum power generation, ramp-up and ramp-down limits and minimum up and down-time. The two energy storage technologies are compared and results show that a management strategy based on this algorithm can reduce significantly the total emissions of the system.

The aim of this article is the evaluation of the topical application of a solution of hydrogen peroxide (H2O2) 8% and dimethyl sulphoxide (DMSO) 50% in order to reduce ischaemic failure in random skin flaps. This study was performed using a rabbit model. Two parallel, cephalad-based para-midline random cutaneous flap (10 cm × 2.5 cm) were elevated and resutured in place on the dorsum of 40 New Zealand rabbits. The 80 flaps thus obtained were then randomly divided into one control group and three experimental groups of 20 flaps each. Flaps from the control group (group A) were topically treated with saline, while flaps from experimental group B were treated with H2O2 8%, flaps from experimental group C with DMSO 50%, and flaps from experimental group D with a solution of 50% DMSO + 8% H2O2. Each solution was topically applied, 20 cc per three times a day, on the flaps for seven days, starting on the immediate postoperative period. Transcutaneous oxygen tension (Ptc O2) measurements were carried out in all flaps, 72 h after flap elevation. The percentage of surviving skin area of each flap was determined by planimetry 7 days after flap elevation. The mean surviving area of the group A (control) flaps was 71%. The mean surviving area of the group B (H2O2-treated) flaps was 72%. The mean surviving area of the group C (DMSO-treated) flaps was 76%, and that of the group D (DMSO + H2O2-treated) flaps was 92%. While no statistically significant differences were found between the survival rates of both the flaps treated with H2O2 or DMSO alone and that of the control group, the mean surviving rate of the DMSO + H2O2 treated flaps (+ 20%) was statistically higher than that of the control flaps. Similarly, a statistically significant difference has been found between the mean Ptc O2 values of the DMSO + H2O2 flaps and those of the other three groups of flaps. [ABSTRACT FROM AUTHOR]