An All-Solid-State Coaxial Structural Battery Using Sodium-Based Electrolyte

The transition to a sustainable society is paramount and requires the electrification of vehicles, the grid, industry, data banks, wearables, and IoT. Here, we show an all-solid-state structural battery where a Na+-based ferroelectric glass electrolyte is combined with metallic electrodes/current collectors (no traditional cathode present at fabrication) and thin-ply carbon-fiber laminates to obtain a coaxial multifunctional beam. This new concept aims to optimize the volume of any hollow beam-like structure by integrating an electrochemical system capable of both harvesting thermal and storing electrical energy while improving its mechanical performance. The coaxial cell is a coaxial cable where the dielectric is ferroelectric. The electrochemical results demonstrated the capability of performing three-minute charges to one-day discharges (70 cycles) and long-lasting discharges (>40 days at 1 mA) showing an energy density of 56.2 Wh center dot L-1 and specific energy of 38.0 Wh center dot kg(-1), including the whole volume and weight of the structural cell. This is the highest specific energy among safe structural cells, while no Na+-based structural cells were found in the literature. The mechanical tests, instead, highlighted the coaxial cell capabilities to withstand severe inelastic deformation without compromising its functionalities, while increasing the flexural strength of the hosting structure. Moreover, the absence of alkali metals and liquid electrolytes together with its enhanced thermal properties makes this coaxial structural battery a valid and safe alternative as an energy reservoir for all the applications where traditional lithium-ion batteries are not suitable

A graphical user interface for the Fastcomp software

FastComp is a computational tool used in mechanical engineering for the determination of the forces that a composite bolted joint subjected to multiaxial loads supports until fracture occurs. The main intention of the present work was the development of a graphical user interface (GUI) for the referred software that allows its parameterization and the visualization of its results.Using VTK, a computational library for graphical objects, visualization and image processing; C#, an object-oriented programming language; and the design principles of a good human/computer interaction, a graphical interface was developed as an efficient and effective means of interaction with the FastComp software

The Latest Trends in Electric Vehicles Batteries

Global energy demand is rapidly increasing due to population and economic growth, especially in large emerging countries, which will account for 90% of energy demand growth to 2035. Electric vehicles (EVs) play a paramount role in the electrification revolution towards the reduction of the carbon footprint. Here, we review all the major trends in Li-ion batteries technologies used in EVs. We conclude that only five types of cathodes are used and that most of the EV companies use Nickel Manganese Cobalt oxide (NMC). Most of the Li-ion batteries anodes are graphite-based. Positive and negative electrodes are reviewed in detail as well as future trends such as the effort to reduce the Cobalt content. The electrolyte is a liquid/gel flammable solvent usually containing a LiFeP6 salt. The electrolyte makes the battery and battery pack unsafe, which drives the research and development to replace the flammable liquid by a solid electrolyte

Application of numerical methods to the strength prediction of mechanically fastened joints in composite laminates.

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Comando de um manipulador electro-hidráulico : relatório final

Relatório de estágio PRODEP III - Medida 4.3 - Acção de Formação n.º 4Estágio realizado no INEGIRelatório de estágio curricular da LEM 1992/1993A informação relativa à instituição de acolhimento de estágio foi fornecida pelo SR

Application of numerical methods to the strength of mechanically fastened joints in composite laminates

Dissertation submitted for the degree of Doctor of Philosophy of the University of London and for the Diploma of Imperial College of Science, Technology and Medicine with the supervision of Dr. Frank Matthew

Aplicação do efeito termoelástico à análise experimental de tensões

Dissertação apresentada para obtenção do grau de Mestre em Engenharia Mecânica, na Faculdade de Engenharia da Universidade do Porto, sob a orientação do Prof. Doutor Paulo Tavares de Castr

Cohesive Elements for Shells

A cohesive element for shell analysis is presented. The element can be used to simulate the initiation and growth of delaminations between stacked, non-coincident layers of shell elements. The procedure to construct the element accounts for the thickness offset by applying the kinematic relations of shell deformation to transform the stiffness and internal force of a zero-thickness cohesive element such that interfacial continuity between the layers is enforced. The procedure is demonstrated by simulating the response and failure of the Mixed Mode Bending test and a skin-stiffener debond specimen. In addition, it is shown that stacks of shell elements can be used to create effective models to predict the inplane and delamination failure modes of thick components. The results indicate that simple shell models can retain many of the necessary predictive attributes of much more complex 3D models while providing the computational efficiency that is necessary for desig

A Micromechanics-Based Damage Model for [± θ / 90n ]s Composite Laminates

A new damage model based on a micromechanical analysis of cracked [± θ / 90n ]s laminates subjected to multiaxial loads is proposed. The model predicts the onset and accumulation of transverse matrix cracks in uniformly stressed laminates, the effect of matrix cracks on the stiffness of the laminate, as well as the ultimate failure of the laminate. The model also accounts for the effect of the ply thickness on the ply strength. Predictions relating the elastic properties of several laminates and multiaxial loads are presentedNASA/TM-2006-21428

Simulation of Delamination Propagation in Composites Under High-Cycle Fatigue by Means of Cohesive-Zone Models

A damage model for the simulation of delamination propagation under high-cycle fatigue loading is proposed. The basis for the formulation is a cohesive law that links fracture and damage mechanics to establish the evolution of the damage variable in terms of the crack growth rate dA/dN. The damage state is obtained as a function of the loading conditions as well as the experimentally-determined coefficients of the Paris Law crack propagation rates for the material. It is shown that by using the constitutive fatigue damage model in a structural analysis, experimental results can be reproduced without the need of additional model-specific curve-fitting parameter