The Experts below are selected from a list of 120 Experts worldwide ranked by ideXlab platform
Lanceros-méndez S. - One of the best experts on this subject based on the ideXlab platform.
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Advances in cathode nanomaterials for lithium-ion batteries
Springer, 2022Co-Authors: Costa, Carlos Miguel Silva, Gonçalves, Renato Ferreira, Lanceros-méndez S.Abstract:Energy resources, consumption, and management are among the most important issues of this century. Our dependence on fossil fuels should be changed by eco-friendlier renewable energies. Further, the generated Electrical Energy should be stored for improving mobile applications, being batteries the most used system for this purpose. Lithium-ion batteries are the most promising battery type and are composed of three main elements: cathode, anode, and separator/electrolyte. The active material of the cathode is primarily responsible for the battery capacity, and for that reason, different cathode materials have been developed and explored for lithium-ion batteries. In the present work, the most relevant cathode materials are presented, their main properties and characteristics described, and their advantage and disadvantage analyzed, allowing to understand to which extent those materials are suitable for specific applications in this field.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013 project PTDC/CTM-ENE/5387/2014, project no. PTDC/FISMAC/28157/2017, and grant SFRH/BPD/112547/2015 (C.M.C.). The authors thank the Basque Government Industry Department under the ELKARTEK and HAZITEK Programs for its financial support
Mustafa Mohammed Kadhim - One of the best experts on this subject based on the ideXlab platform.
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Manufacturing a Refrigerator with Heat Recovery Unit
Journal of University of Babylon, 2018Co-Authors: Mustafa Mohammed KadhimAbstract:This study aims to exploite the rejected heating Energy from condenser and benefit from it to reheat the foods and other materials. It can also be employed to improve the coefficient of performance of a refrigerator at the same time by using approximately the same consumption Electrical Energy used to operate the compressor and refrigerator in general. This idea has been implemented by manufacturing of a refrigerator with using additional part has the same metal and condenser pipe diameters but its surface area does not exceed 40% from total surface area of the condenser and its design as an insulated cabinet from all sides to prevent heat leakage through it and located between the compressor and the condenser. Small Electrical fan has been added inside this cabinet to provide a suitable air circulation and a homogenous temperature distribution inside the cabinet space. It is expected that the super heating Energy of refrigerant (R134a) which comes out of the compressor would be removed inside this cabinet and this insist to condensate the refrigerant (cooling fluid) with a rate higher than that used in the normal refrigerator only. Three magnetic valves have been used in order to control the refrigerant flow in state of operation the refrigerator only or to gather with heating cabinet. To measure the temperatures at each process of the simple vapor compression refrigeration cycle, nine temperature sensors at input and output of each compressor, condenser and an evaporator in additional to input of cabinet and inside it and on evaporator surface have been provided. Five pressure gages have been used to measure the value of pressure and compare it for the two states of operation. The consumption of Electrical Energy can be calculated by adding an ammeter and a voltmeter and compare between the consumption Energy of both states. The obtained results show that there is an improvement in the coeffecient of performance in state of operation the refrigerator with heat recovery cabinet by 20% more than that of the operation of refrigerator only. This improvement is due to the reduction in the condenser exit temperature by 4 to 6 C˚, and the super heat removing process in reheating cabinet. The temperature of the cabinet reachs to 60 C˚ which is a sufficient for the food heating. A small amount of refrigerant pressure reduction due to these additions, and its effect on the preformace of the refrigerator may be not considerable.
Kim Jaewoo - One of the best experts on this subject based on the ideXlab platform.
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Flexible Thin Film Lithium Ion Rechargeable Battery
1Co-Authors: Kim JaewooAbstract:The purpose of this project is to fabricate a micro-size lithium ion battery for bio-integrated devices. The battery is to be integrated into an animal’s heart so that when the piezoelectric device converts the mechanical Energy of heart into Electrical Energy, the battery can store it for later use. The project mainly focuses on the fabrication of a lithium ion battery with better performance (higher capacity and longer life cycle) on flexible substrates. Two methods of fabrication are currently in progress. One is to build a battery on Kapton film with a solid electrolyte, Lithium Phosphorus Oxynitride (LiPON) and the second method uses a flexible aluminum pouch substrate with liquid electrolyte inside. Once the fabrication conditions are optimized and the performance of the battery is achieved, it will be redesigned into micro-size for bio integration purposes. A number of challenges exist, such as oxidation of lithium along the fabrication process, deformation of the flexible substrate during the post annealing process which causes the degradation of the battery performance, and leakage of a liquid electrolyte in an aluminum pouch cell.unpublishednot peer reviewedU of I OnlyUndergraduate senior thesis not recommended for open acces
Ma Shengxiang - One of the best experts on this subject based on the ideXlab platform.
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A Class of Solid-like Electrolytes for Rechargeable Batteries Based on Metal-Organic Frameworks Infiltrated with Liquid Electrolytes
eScholarship University of California, 2020Co-Authors: Ma ShengxiangAbstract:Energy storage and conversion are key technologies in modern society, and they are becoming more and more important. This is mainly due to the severe future impact of fossil fuels on the world’s economy and ecology. So, there is an urgent need for alternative Energy sources to address the depletion of fossil fuels and the environmental impact of their continued use. However, the large-scale development of renewable Energy resources such as wind, solar, geothermal, biomass and hydropower, that are unpredictable and intermittent. Thus, these technologies require highly reliable Electrical Energy storage (EES) devices, which can store the excess produced electricity and release it on demand. Rechargeable batteries such as lithium-ion batteries, store Energy through electrochemical reactions that typically occur throughout the bulk active materials, allowing comparatively large amount of Energy to be stored compared with electric capacitors. The last decade has witnessed a tremendous growth in lithium-ion batteries for applications such as microelectronics and electric vehicles. However, the development of battery Energy density has seriously lagged behind the demand growth of Li-ion batteries. Thus, high Energy density electrode materials are extremely demanded in next-generation cutting-edge electronic devices. Parallel to this development, rechargeable batteries based on Na+, K+, Mg2+ and Al3+ ions have also attracted great interests due to their abundance and low cost.Such batteries generally employ flammable liquid electrolytes, which bring severe safety concerns. In this case, solid electrolytes are believed to be able to suppress Li dendrite growth because of their high mechanical strength and high Li+ transference number. In order to allow the implementation of high-specific-Energy Li-metal batteries, both inorganic and organic solid electrolytes have been explored. Inorganic electrolytes may exhibit high ionic conductivity (e.g., > 10–4 S cm–1), whereas scale fabrication of solid batteries remains challenging. Polymeric electrolytes are less difficult to be integrated, whereas their ionic conductivity remains low at ambient temperature (e.g., < 10–5 S cm–1). Solid-like electrolytes, which are generally made by encapsulating liquid electrolytes within solid porous scaffolds, represent another direction with the merits of both liquid electrolyte and solid electrolyte. In this dissertation, we developed a novel family of solid-like electrolytes, which are made by infiltrating MIL-100(Al), a MOF with high porosity and excellent thermal, chemical and electrochemical stabilities, with a series of liquid electrolytes that contain cations from the 3rd period (Na+, Mg2+ and Al3+) and the 1st group (Li+, Na+, K+ and Cs+). Particularly, the Mg2+ solid-like electrolyte exhibits superionic conductivity (>10–3 S cm–1) with a low activation Energy of 0.20 eV. From Li+, Na+, K+ to Cs+ with reducing Stokes radii and ionic solvation shell thickness, both the liquid electrolytes and solid-like electrolytes show a similar trend of increasing conductivity. This work investigates the ion-conduction mechanism of MOFs based solid-like electrolytes, providing reliable principles to the design of fast-conducting solid-like electrolytes for alkali or multivalent metal ions. Furthermore, we successfully employed MOF-based solid-like electrolytes in Na-metal batteries. Both MOF/polymer composite electrolytes on GF served as functional separator or directly as gel polymer electrolytes show advantages compared with commercial separators. The cell using solid-like electrolyte notably surpasses the cell using liquid electrolyte in terms of cycle stability and Coulombic efficiency. This work expands the application of MOF-based solid-like electrolytes from Li to Na metal batteries, offering the possibility for further applications in high Energy density rechargeable batteries
Van Cutsem, Olivier Valenti Henri - One of the best experts on this subject based on the ideXlab platform.
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On Smart-Buildings and their Integration into the Smart-Grid
Lausanne EPFL, 2020Co-Authors: Van Cutsem, Olivier Valenti HenriAbstract:Today's Electrical grid is undergoing deep changes, resulting from the large integration of distributed Renewable Energy Sources (RES) in an effort to decarbonize the generation of Electrical Energy. In addition to the emergence of this volatile electricity production, the worldwide demand for electricity increases due to a growing population and the intensified electrification of buildings. Smart-buildings represent promising assets for supporting the Electrical grid in balancing demand with a supply based on non-dispatchable RES. A smart-building denotes a building equipped with sensor/actuator hardware connected to a federating Building Data Management System (BDMS) which enables high-level applications and services. Tapping into the flexibility inherent to its various entities (load, storage, and generation), a smart-building can provide Demand Response (DR) functionality through the optimization of its Energy profile in response to varying electricity prices or commands from the grid.This PhD thesis provides a set of tools, algorithms, and frameworks, revolving around the notion of smart-buildings that foster an enhanced Building-to-Grid (BtG) integration. The tools developed here aim to fill the gap encountered in the literature created by the recent rollout of BDMSs and the ubiquitous Internet of Things (IoT). Furthermore, the mismatch between current DR and the future RES-based smart-grid opens the way to the development of innovative algorithms and frameworks to manage the flexibility offered by smart-buildings for grid-side agents. Built upon BDMSs, two open-source tools have been developed. Firstly, an integrated high-speed emulation and simulation software, dubbed Virtualization Engine (vEngine), allows the simulation of non-existing components of a building directly on-site. The multi-threaded, light architecture of vEngine permits efficient simulations, in a modular environment conceived for developers. Secondly, we describe Open Energy Management System (OpenEMS), a platform that seamlessly connects to any existing BDMS and provides its users with an environment to create their own Energy management algorithms, with a focus on Model Predictive Control (MPC). Simulations using a realistic Swiss residential building model demonstrate the effectiveness and modularity of both tools. Additionally, we propose a multi-state load profile identification algorithm tailored to Non-Intrusive Load Monitoring (NILM). Applied to Energy disaggregation, it shows promising results for enhanced Energy feedbacks to the occupants. To attain daily Energy balance within the smart-grid, we propose several algorithms and Energy management frameworks, using smart-buildings. An incremental MPC formulation is derived to better balance monthly costs associated to Energy and peak demand of large commercial buildings. Simulations data show substantial benefits, for both the building's owner and the grid. Furthermore, we present a decentralized framework for autonomously managing the Energy in a community of smart-buildings, with RES. Based on blockchain technology and smart-contracts, the framework optimizes an objective common to the whole community without the need for a central agent. Finally, we suggest a unified BtG model that could benefit grid-side aggregators in both microgrids and electricity markets
