Relevant bibliographies by topics / Electrodes positives

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Academic literature on the topic 'Electrodes positives'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Electrodes positives"

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Straka, Malgorzata, Benjamin Shafer, Srikanth Vasudevan, Cristin Welle, and Loren Rieth. "Characterizing Longitudinal Changes in the Impedance Spectra of In-Vivo Peripheral Nerve Electrodes." Micromachines 9, no. 11 (November 12, 2018): 587. http://dx.doi.org/10.3390/mi9110587.

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Characterizing the aging processes of electrodes in vivo is essential in order to elucidate the changes of the electrode–tissue interface and the device. However, commonly used impedance measurements at 1 kHz are insufficient for determining electrode viability, with measurements being prone to false positives. We implanted cohorts of five iridium oxide (IrOx) and six platinum (Pt) Utah arrays into the sciatic nerve of rats, and collected the electrochemical impedance spectroscopy (EIS) up to 12 weeks or until array failure. We developed a method to classify the shapes of the magnitude and phase spectra, and correlated the classifications to circuit models and electrochemical processes at the interface likely responsible. We found categories of EIS characteristic of iridium oxide tip metallization, platinum tip metallization, tip metal degradation, encapsulation degradation, and wire breakage in the lead. We also fitted the impedance spectra as features to a fine-Gaussian support vector machine (SVM) algorithm for both IrOx and Pt tipped arrays, with a prediction accuracy for categories of 95% and 99%, respectively. Together, this suggests that these simple and computationally efficient algorithms are sufficient to explain the majority of variance across a wide range of EIS data describing Utah arrays. These categories were assessed over time, providing insights into the degradation and failure mechanisms for both the electrode–tissue interface and wire bundle. Methods developed in this study will allow for a better understanding of how EIS can characterize the physical changes to electrodes in vivo.
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Martins, Beatriz R., Yanne O. Barbosa, Cristhianne M. R. Andrade, Loren Q. Pereira, Guilherme F. Simão, Carlo J. de Oliveira, Dalmo Correia, et al. "Development of an Electrochemical Immunosensor for Specific Detection of Visceral Leishmaniasis Using Gold-Modified Screen-Printed Carbon Electrodes." Biosensors 10, no. 8 (July 23, 2020): 81. http://dx.doi.org/10.3390/bios10080081.

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Visceral leishmaniasis is a reemerging neglected tropical disease with limitations for its diagnosis, including low concentration of antibodies in the serum of asymptomatic patients and cross-reactions. In this context, this work proposes an electrochemical immunosensor for the diagnosis of visceral leishmaniasis in a more sensitive way that is capable of avoiding cross-reaction with Chagas disease (CD). Crude Leishmania infantum antigens tested in the enzyme-linked immunosorbent assay (ELISA) were methodologically standardized to best engage to the sensor. The antibodies anti-Trypanosoma cruzi and anti-Leishmania sp. Present in serum from patients with diverse types of CD or leishmaniasis were chosen. A screen-printed carbon electrode modified with gold nanoparticles was the best platform to guarantee effective adsorption of all antigens so that the epitope of specific recognition for leishmaniasis occurred efficiently and without cross-reaction with the evaluated CD. The current peaks reduced linearly after the recognition, and still were able to notice the discrimination between different kinds of diseases (digestive, cardiac, undetermined Chagas/acute and visceral chronic leishmaniasis). Comparative analyses with ELISA were performed with the same groups, and a low specificity (44%) was verified due to cross-reactions (high number of false positives) on ELISA tests, while the proposed immunosensor presented high selectivity and specificity (100%) without any false positives or false negatives for the serum samples from isolated patients with different types of CD and visceral leishmaniasis. Furthermore, the biosensor was stable for 5 days and presented a detection limit of 200 ng mL−1.
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Elvira, María, Eduardo Iáñez, Vicente Quiles, Mario Ortiz, and José M. Azorín. "Pseudo-Online BMI Based on EEG to Detect the Appearance of Sudden Obstacles during Walking." Sensors 19, no. 24 (December 10, 2019): 5444. http://dx.doi.org/10.3390/s19245444.

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The aim of this paper is to describe new methods for detecting the appearance of unexpected obstacles during normal gait from EEG signals, improving the accuracy and reducing the false positive rate obtained in previous studies. This way, an exoskeleton for rehabilitation or assistance of people with motor limitations commanded by a Brain-Machine Interface (BMI) could be stopped in case that an obstacle suddenly appears during walking. The EEG data of nine healthy subjects were collected during their normal gait while an obstacle appearance was simulated by the projection of a laser line in a random pattern. Different approaches were considered for selecting the parameters of the BMI: subsets of electrodes, time windows and classifier probabilities, which were based on a linear discriminant analysis (LDA). The pseudo-online results of the BMI for detecting the appearance of obstacles, with an average percentage of 63.9% of accuracy and 2.6 false positives per minute, showed a significant improvement over previous studies.
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Tsai, Shan-Ho, Ying-Ru Chen, Yi-Lin Tsou, Tseng-Lung Chang, Hong-Zheng Lai, and Chi-Young Lee. "Applications of Long-Length Carbon Nano-Tube (L-CNT) as Conductive Materials in High Energy Density Pouch Type Lithium Ion Batteries." Polymers 12, no. 7 (June 30, 2020): 1471. http://dx.doi.org/10.3390/polym12071471.

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Lots of lithium ion battery (LIB) products contain lithium metal oxide LiNi5Co2Mn3O2 (LNCM) as the positive electrode’s active material. The stable surface of this oxide results in high resistivity in the battery. For this reason, conductive carbon-based materials, including acetylene black and carbon black, become necessary components in electrodes. Recently, carbon nano-tube (CNT) has appeared as a popular choice for the conductive carbon in LIB. However, a large quantity of the conductive carbon, which cannot provide capacity as the active material, will decrease the energy density of batteries. The ultra-high cost of CNT, compared to conventional carbon black, is also a problem. In this work, we are going to introduce long-length carbon nano-tube s(L-CNT) into electrodes in order to design a reduced-amount conductive carbon electrode. The whole experiment will be done in a 1Ah commercial type pouch LIB. By decreasing conductive carbon as well as increasing the active material in the positive electrode, the energy density of the LNCM-based 1Ah pouch type LIB, with only 0.16% of L-CNT inside the LNCM positive electrode, could reach 224 Wh/kg and 549 Wh/L, in weight and volume energy density, respectively. Further, this high energy density LIB with L-CNT offers stable cyclability, which may constitute valuable progress in portable devices and electric vehicle (EV) applications.
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Mittmann, Philipp, Ingo Todt, Arneborg Ernst, Grit Rademacher, Sven Mutze, Sophia Göricke, Marc Schlamann, Stephan Lang, Diana Arweiler-Harbeck, and Florian Christov. "Radiological and NRT-Ratio–Based Estimation of Slim Straight Cochlear Implant Electrode Positions." Annals of Otology, Rhinology & Laryngology 126, no. 1 (October 25, 2016): 73–78. http://dx.doi.org/10.1177/0003489416675355.

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Objectives: An intraoperative neural response telemetry-ratio (NRT-ratio) was established, which can provide information about the intraoperative intracochlear electrode array position for perimodiolar electrodes. Methods: In a retrospective controlled study in 2 tertiary referral centers, the electrophysiological data sets of 50 patients with measured intraoperative auto-NRTs and postoperative radiological examinations were evaluated. All patients were implanted with Nucleus slim straight electrodes. The NRT-ratio was calculated by dividing the average auto-NRT data from electrodes 16 to 18 with the average from electrodes 5 to 7. Using a flat panel tomography system or a computed tomography, the position of the electrode array was certified radiological. Results: Radiologically, 2 out of 50 patients were identified with an electrode translocated from the scala tympani into the scala vestibuli. The radiologically estimated electrodes indicating a scalar change showed a regular NRT-ratio but nonspecific NRT-level changes at the localization of translocation.
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Santos, V. E. O., V. G. Celante, M. F. F. Lelis, and M. B. J. G. Freitas. "Chemical and electrochemical recycling of the nickel, cobalt, zinc and manganese from the positives electrodes of spent Ni–MH batteries from mobile phones." Journal of Power Sources 218 (November 2012): 435–44. http://dx.doi.org/10.1016/j.jpowsour.2012.07.024.

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Wu, Jian Bo, Yong Feng Yuan, and Wei Ping Chen. "CNT-CoO Complex Conductive Agent for the Positive Electrodes of MH/Ni Batteries." Materials Science Forum 610-613 (January 2009): 488–91. http://dx.doi.org/10.4028/www.scientific.net/msf.610-613.488.

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CoO was usually added to the positive electrodes of MH/Ni batteries as the conductive agent. In this paper, well crystallized multi-walled carbon nanotubes (CNTs) with diameter about 10 nm were added to the positive electrodes of MH/Ni batteries together with CoO. During the process of transformation from CoO to CoOOH, a complex conductive network was created with CNTs as the frame. Because of the high conductivity and the excellent tension characteristics of CNTs, the charge-transfer capability of the electrode was improved and the integrality of the complex conductive network was enhanced. The electrochemical measurements indicated that the impedance of the electrode with CNT-CoO complex conductive agent was lessened compared to the electrode with simple CoO agent. Performance tests of the sealed batteries showed that the positive electrodes with CNT-CoO complex conductive agent exhibited higher discharge voltage, improved capacity, modified discharge stability and prolonged lifespan, especially at high current rates.
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Zheng, H. Z., Y. J. Zhu, Z. J. Zhang, X. R. Lin, Z. J. Zhou, X. C. Ye, and S. G. Wu. "The Effect of Electrodes’ Making Methods on the Electrochemical Performance of Nano-Ni(OH)2." Applied Mechanics and Materials 79 (July 2011): 123–27. http://dx.doi.org/10.4028/www.scientific.net/amm.79.123.

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Nano-Ni(OH)2 doped with special elements were prepared by supersonic co-precipitation method. Complex electrodes were prepared by immersion method and handwork method by mixing 8wt.% nickel hydroxides with commercial micro-size spherical nickel as the positive material of Ni-MH battery. The electrochemical performance and cyclic character affected by different electrodes’ making methods were characterized in this article. The result indicates that the discharge capacities of IM electrodes (IM electrodes mean electrodes made by handwork method) are higher than that of HM electrodes (HM electrodes mean electrodes made by handwork method). Furthermore, IM electrodes have better reversibility and higher charge efficiency than HM electrode, and lower charge potential and higher discharge plateau were also observed for IM electrodes. It's worth noting that the phenomenon is more obvious at high charge/discharge rate. When the discharge rate is 0.5C，the discharge capacity of IM electrode is higher 67.1 mAh•g -1 than that of HM electrode.
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Eliseeva, Svetlana N., Mikhail A. Kamenskii, Elena G. Tolstopyatova, and Veniamin V. Kondratiev. "Effect of Combined Conductive Polymer Binder on the Electrochemical Performance of Electrode Materials for Lithium-Ion Batteries." Energies 13, no. 9 (May 1, 2020): 2163. http://dx.doi.org/10.3390/en13092163.

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The electrodes of lithium-ion batteries (LIBs) are multicomponent systems and their electrochemical properties are influenced by each component, therefore the composition of electrodes should be properly balanced. At the beginning of lithium-ion battery research, most attention was paid to the nature, size, and morphology peculiarities of inorganic active components as the main components which determine the functional properties of electrode materials. Over the past decade, considerable attention has been paid to development of new binders, as the binders have shown great effect on the electrochemical performance of electrodes in LIBs. The study of new conductive binders, in particular water-based binders with enhanced electronic and ionic conductivity, has become a trend in the development of new electrode materials, especially the conversion/alloying-type anodes. This mini-review provides a summary on the progress of current research of the effects of binders on the electrochemical properties of intercalation electrodes, with particular attention to the mechanisms of binder effects. The comparative analysis of effects of three different binders (PEDOT:PSS/CMC, CMC, and PVDF) for a number of oxide-based and phosphate-based positive and negative electrodes for lithium-ion batteries was performed based on literature and our own published research data. It reveals that the combined PEDOT:PSS/CMC binder can be considered as a versatile component of lithium-ion battery electrode materials (for both positive and negative electrodes), effective in the wide range of electrode potentials.
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Lim, Jong-Min, and Chung-Seog Choi. "Study on the Analysis of Restrike Pattern and Radial Spectrum of AC Arc Discharge based on the Electrode Material." Fire Science and Engineering 35, no. 4 (August 31, 2021): 58–64. http://dx.doi.org/10.7731/kifse.2c23dfaa.

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In this study, we designed and fabricated a system based on IEC-62606 and UL-1699 such that stable arc discharge could be produced. AC arc discharge was performed to interpret the restrike pattern and radiation spectrum according to the electrode material. In the voltage waveform analysis of flat copper electrodes, it was analyzed that the accompaniment cycle of the negative waveform was more unstable than the half cycle of the positive waveform. We observed that the radiation spectrum of copper electrodes occurred in the ultraviolet and visible light regions. Moreover, the voltage waveform of the carbon electrode was found to be similar to the pattern produced by the copper electrode. However, we observed that the restrike generated at the half cycle of the negative waveform was produced relatively faster. The radio spectra were strongest near 589 nm, 671 nm, and 766 nm. AC arc discharges using copper electrodes and carbon electrodes were found to be between the arc-discharge patterns of copper electrodes and carbon electrodes. It has been proven that depending on the material of the electrode, there are differences in voltage list like, current patterns, and radiated spectra bands.
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Dissertations / Theses on the topic "Electrodes positives"

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Van, Staen Guilherme. "Electrodes positives à base de cuivre pour accumulateurs Li-ion." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066165/document.

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Les accumulateurs Li-ion sont des systèmes de stockage électrochimique de l’énergie composés de deux électrodes, dans lesquelles les ions Li+ vont venir s’insérer réversiblement lors des cycles de charge et de décharge. Afin d’intégrer le domaine des véhicules électriques, leur densité d’énergie doit être augmentée pour apporter l’autonomie demandée. Ceci peut être réalisé en augmentant la d.d.p. entre les deux électrodes. Nous visons ici la synthèse de nouveaux matériaux polyanioniques d’électrode positive dans lesquels le lithium pourrait venir s’insérer à haut potentiel en faisant intervenir le couple Cu3+/Cu2+ (5,3 V vs Li+/Li). Parmi les phosphates de cuivre synthétisés, Li2CuP2O7 présente une oxydation non réversible à haut potentiel (> 5 V). Sa synthèse à basse température permet d’exacerber les réactions, en raison de la faible taille des particules obtenues ainsi que de la présence de carbone conducteur à leur surface, mais la phase s’avère instable à haut potentiel.En ce qui concerne les composés de type sulfate, une nouvelle phase Li4Cu4O2(SO4)4 est isolée, montrant une insertion réversible du lithium à une valeur moyenne de 4,7 V. Cependant, la capacité de ce matériau est très faible (15 mAh.g-1) et plusieurs substitutions chimiques avec du fluor, du magnésium ou du sodium sont étudiées dans le but d’augmenter la mobilité du lithium
Li-ion batteries (LIBs) are energy storing electrochemical devices composed of two electrodes, in which Li+ ions are reversibly inserted during charge and discharge cycles. Their use in electric vehicles relies on the increase of their energy density, to provide enough autonomy. This can be reached by increasing the cell d.d.p. We thus aim the synthesis of new positive electrode polyanionic materials, in which lithium could be inserted at high potential, using the Cu3+/Cu2+ couple’s activity (5,3 V vs Li+/Li). Among the synthesized copper phosphates, Li2CuP2O7 presents a non-reversible oxidation at high potential (>5 V). Its low temperature synthesis intensifies the reaction, due to the smaller particle size achieved as well as the presence of a conductive carbon coating, but the phase is instable at high potential. Concerning sulfate-type compounds, a new phase Li4Cu4O2(SO4)4 is isolated, showing a reversible lithium insertion at an average value of 4.7 V. Nevertheless, its capacity is very low (15 mAh.g-1) and various chemical substitutions with fluorine, magnesium or sodium are attempted to increase lithium’s mobility
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Dubois, Vincent. "Electrodes positives lithiées d’oxysulfures de titane pour microbatteries Li-ion." Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR14858/document.

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Le développement à grande échelle des microbatteries pour des applications diverses comme l’alimentation de secours de certains composants électroniques dans les téléphones portables nécessite une compatibilité avec le procédé de solder-reflow employé dans le domaine de la microélectronique. Dans ce contexte, cette étude porte sur la mise au point d’un nouveau procédé de réalisation de couches minces d’oxysulfures de titane lithiés (LixTiOySz) pour une utilisation en tant qu’électrode positive dans une microbatterie Li-ion. Tout d’abord ce travail a débuté par la synthèse et la caractérisation de plusieurs compositions de sulfures de titane lithiés à l’état massif par réaction en solution de TiS2 ou TiS3 avec le n-butyllithium mais aussi par réaction à l’état solide à haute température entre les précurseurs TiS2, Li2S et Ti. Par la suite, des couches minces de LixTiOySz ont été déposées par pulvérisation cathodique radiofréquence à effet magnétron de cibles réalisées à partir des matériaux lithiés à l’état massif. La composition chimique de ces dépôts dépend de celle de la cible utilisée ce qui permet d’obtenir des couches plus ou moins riches en lithium et en soufre. En revanche, elles sont toutes très mal cristallisées, denses et elles ne présentent pas de structuration particulière. Enfin, les caractérisations électrochimiques des dépôts de LixTiOySz, à la fois en électrolyte liquide et solide, ont permis de mettre en évidence une corrélation entre leur composition chimique et leur comportement électrochimique. Globalement, ces dernières sont performantes, compatibles avec le solder-reflow et donc tout à fait intéressante pour l’application
Large-scale development of microbatteries for various applications such as back-up power sources for cell phone electronic components needs suitability with reflowing process that is often used in microelectronic. Here we report on the development of a new realization process to produce lithiated titanium oxysulfides (LixTiOySz) thin films for use as positive electrode in Li-ion microbatteries. First of all, this work began with synthesis and characterization of several lithiated titanium sulfides compounds prepared by reaction between TiS2 or TiS3 with n-butyllithium but also by solid state reaction at high temperature between TiS2, Li2S and Ti. Then, LixTiOySz thin films were sputtered by magnetron effect radio-frequency sputtering from targets made of lithiated materials previously synthesized. The chemical composition of those films depends on the target one and allows obtaining thin films with different lithium and sulfur contents. In contrast, they are all amorphous, dense and they don’t have a morphological structuration. Finally, electrochemical characterizations of thin films, both in liquid and solid electrolyte, have highlighted a correlation between their chemical composition and their electrochemical behavior. Taken as a whole, LixTiOySz thin films are powerful, suitable with reflowing process and thus very interesting for the application
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ZANINOTTO, FRANCK. "Etude des mecanismes de vieillissement des electrodes positives des accumulateurs plomb-acide." Paris 6, 1998. http://www.theses.fr/1998PA066370.

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Les accumulateurs plomb-acide possedent des applications tres diverses. Leur faible cout de fabrication, leur recyclage aise en font de bons candidats comme moyens de stockage d'energie sur vehicule electrique. Toutefois, les accelerations, les freinages et les pauses repetitives generent des contraintes qui tendent a reduire la duree de vie des accumulateurs en alterant la matiere active des electrodes positives. L'objectif de l'etude presentee dans ce memoire est de comprendre les mecanismes de vieillissement du pbo 2 de l'electrode positive et de rechercher des solutions permettant de retarder cette degradation dans le cadre d'une utilisation intensive sur vehicule electrique. Pour ce faire, nous avons elabore des cellules de cyclage specifiques permettant d'accelerer la degradation de l'electrode positive. L'influence du type de cyclage sur la perte de capacite a ete etudiee. Nous nous sommes interesse plus particulierement a l'evolution texturale de la matiere positive pendant le cyclage : les resultats experimentaux mettent en evidence une croissance continue de la microstructure du pbo 2. De la meme maniere, ces travaux ont permis d'etablir le lien direct entre la croissance nanotexturale du pbo 2 et la decohesion de la matiere active positive. Ce vieillissement textural a pu etre modelise a l'aide d'un modele mathematique assimilant les cristaux de pbo 2 a un reseau de spheres jointives. Des essais complementaires montrent que l'ajout d'acide orthophosphorique joue un role favorable dans le maintien des performances des cellules au cours du cyclage en maintenant la stabilite texturale de la matiere active. D'autres tests montrent que l'utilisation d'un traitement electrique specifique permet de restaurer ponctuellement la capacite des accumulateurs grace a une regeneration texturale partielle de la masse active.
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Franger, Sylvain. "Synthese, caracterisation et etude des proprietes electrochimiques de nouveaux oxydes de manganese pour electrodes positives d'accumulateurs au lithium." Paris 6, 2001. http://www.theses.fr/2001PA066094.

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Apres avoir reexamine en detail, dans une premiere partie, l'ensemble des caracteristiques electrochimiques de la birnessite sol-gel, mno 1 , 8 4. 0,6 h 2o, en particulier grace a une etude detaillee de la cinetique de transport du lithium dans le materiau, une reponse appropriee a ete apporte a la baisse constante de capacite en cyclage grace a un dopage de la structure birnessite par le cobalt. Des capacites specifiques stables en cyclage sont alors obtenues avec 170 ah/kg au bout du quarantieme cycle a c/20. Les variations structurales fortement amoindries, dans le cas du compose au cobalt, sont responsables de l'amelioration constatee. En effet, dans le domaine d'utilisation de 4,2 v a 2v, la transition hexagonale monoclinique qui a lieu au cours du processus d'intercalation dans la birnessite sol-gel n'est jamais observee dans le cas du compose au cobalt. Dans une seconde partie, nous avons synthetise toute une famille de composes lamellaires de formule li ymn 1 xm xo 2 +. Prepares par echange d'ions a reflux a 100\c en milieu aqueux a partir de na 0 , 7mno 2 +. Les composes li ymn 1 xm xo 2 +. Obtenus apres traitement thermique a 200 et a 300\c presentent des courbes de decharge - charge uniforme, mais d'un point de vue structurale sont constituees majoritairement d'une phase lamellaire hexagonale et tres minoritairement d'une phase spinelle. L'etude chronopotentiometrique de ces composes a demontre que le comportement le plus performant etait obtenu pour le compose dope au cobalt avec un taux optimum de x = 0,15. Ce materiau s'est revele remarquable de par ses caracteristiques electrochimiques avec 190 ah/kg recuperes au bout du quarantieme cycle contre 170 ah/kg pour le compose non dope. De telles valeurs stables sont parmi les plus elevees jamais obtenues dans le cas des oxydes de manganese lamellaires. Nous avons pu montrer en outre que la cinetique de transport du lithium etait superieure de 1 a 2 ordres de grandeur a celles obtenues dans les birnessites sol-gel.
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Rougier, Aline. "Relation entre la structure et le comportement electrochimique des phases LixNi1-yMyO2 (M = Al, Fe, Co). Materiaux d' electrodes positives pour batteries au lithium." Phd thesis, Université Sciences et Technologies - Bordeaux I, 1995. http://tel.archives-ouvertes.fr/tel-00145612.

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Le nickelate de lithium "LiNiO2" est actuellement l'un des matériaux d'électrode positive pour batteries au lithium les plus etudies. Cependant, "LiNiO2" stoechiométrique n'existe pas, la formule réelle est Li1-zNi1+zO2. La présence de ces (z) ions nickel excédentaires entraine une diminution significative des performances électrochimiques. Une étude structurale fine (méthode de Rietveld), couplée à une étude magnétique, a permis de quantifier de façon précise l'écart a la stoechiométrie (z). L'influence de divers substituants sur les propriétés structurales, physiques et électrochimiques a également été étudiée.
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Storck-Gantois, Fanny. "Effet de la compression et de l’ajout d’additifs sur l’amélioration des performances d’un accumulateur au plomb." Paris 6, 2008. http://www.theses.fr/2008PA066370.

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Les travaux de cette thèse visent le développement d’un accumulateur au plomb-acide aux propriétés améliorées en combinant l’utilisation d’additifs et la mise en compression des cellules. L’utilisation d’additifs poreux vise à favoriser la diffusion de l’électrolyte au sein de la matière active positive et l’utilisation d’additifs de conductivité tend à optimiser le réseau de conduction des matériaux actifs. Le maintien de la cohésion des matières en cyclage est assuré par la mise en compression des électrodes. Dans cet objectif, un protocole de fabrication d’électrodes positives a été développé au laboratoire. Un comportement de référence a ensuite été définit en déterminant les performances électriques et les caractéristiques des électrodes témoins soumises à des pressions allant de 0 à 1bar. Puis les effets des additifs ont été évalués lors d’applications en compression. Notre but étant également une meilleure compréhension du système plomb-acide et du mode de fonctionnement des additifs, des mécanismes pour expliquer l’évolution texturale des matériaux actifs positifs en compression et l’interaction entre les additifs et l’application d’une pression ont été proposés
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Soudan, Patrick. "Etude des proprietes electrochimiques de nouveaux oxydes et bronzes de type m yv 2o 5 prepares par voie sol-gel et utilisables comme electrodes positives d'accumulateurs au lithium." Paris 6, 1998. http://www.theses.fr/1998PA066625.

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Ce travail se situe dans le cadre de l'amelioration des performances des materiaux cathodiques pour accumulateurs au lithium. La synthese sol-gel est utilisee ici pour obtenir des composes de type m yv 2o 5 : un bronze hexagonal cs 0. 3 5v 2o 5 et des oxydes mixtes orthorhombiques m 0. 1 6v 2o 5. 1 6 (m 2 + = mg 2 +, mn 2 +, ni 2 +) et m 0. 1 1v 2o 5. 1 6 (m 3 + = al 3 +, cr 3 +, fe 3 +, ga 3 +, la 3 +). Leurs proprietes electrochimiques et structurales sont etudiees vis a vis de l'insertion du lithium. Dans une premiere partie sont mises en evidence les differences majeures entre v 2o 5 et les oxydes mixtes. La presence de cations divalents limite les deformations structurales qui se produisent pour x > 1 dans li xv 2o 5, alors que les ions trivalents al 3 +, cr 3 +, ga 3 + et la 3 + les empechent totalement. Le gain de capacite en cyclage par rapport a v 2o 5 sol-gel est de 10% pour le groupe m 0. 1 6v 2o 5. 1 6 et de 25% pour le groupe m 0. 1 1v 2o 5. 1 6. La deuxieme partie est consacree a l'oxyde mixte cr 0. 1 1v 2o 5. 1 6 qui est le plus performant. L'etude structurale sur electrodes des materiaux li xcr 0. 1 1v 2o 5. 1 6 pour 0x2 revele un comportement de type monophase, qui se distingue de l'apparition successive des phases , , et du systeme li xv 2o 5. Les mesures cinetiques indiquent un changement important de morphologie pour x > 1, avec une diminution d'un facteur 10 de la longueur du chemin de diffusion. L'obtention d'un materiau reduit par traitement sous ar/h 2 constitue une nouvelle voie de synthese par rapport au compose vo 2(b) nanocristallin mentionne dans la litterature, et offre une capacite specifique aussi elevee. Dans la troisieme partie est etudiee l'insertion electrochimique du lithium dans le bronze cs 0. 3 5v 2o 5. La premiere etape correspond au remplissage des 0. 65 sites 2c et 4e vacants et la deuxieme acheve la reduction du vanadium v. Une mise en forme du materiau est observee en cours de cyclage entre 1. 8 v et 4. 2 v, conduisant a une augmentation de la capacite specifique de 25%.
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Blidberg, Andreas. "Iron Based Materials for Positive Electrodes in Li-ion Batteries : Electrode Dynamics, Electronic Changes, Structural Transformations." Doctoral thesis, Uppsala universitet, Strukturkemi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-317014.

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Li-ion battery technology is currently the most efficient form of electrochemical energy storage. The commercialization of Li-ion batteries in the early 1990’s revolutionized the portable electronics market, but further improvements are necessary for applications in electric vehicles and load levelling of the electric grid. In this thesis, three new iron based electrode materials for positive electrodes in Li-ion batteries were investigated. Utilizing the redox activity of iron is beneficial over other transition metals due to its abundance in the Earth’s crust. The condensed phosphate Li2FeP2O7 together with two different LiFeSO4F crystal structures that were studied herein each have their own advantageous, challenges, and scientific questions, and the combined insights gained from the different materials expand the current understanding of Li-ion battery electrodes. The surface reaction kinetics of all three compounds was evaluated by coating them with a conductive polymer layer consisting of poly(3,4-ethylenedioxythiophene), PEDOT. Both LiFeSO4F polymorphs showed reduced polarization and increased charge storage capacity upon PEDOT coating, showing the importance of controlling the surface kinetics for this class of compounds. In contrast, the electrochemical performance of PEDOT coated Li2FeP2O7 was at best unchanged. The differences highlight that different rate limiting steps prevail for different Li-ion insertion materials. In addition to the electrochemical properties of the new iron based energy storage materials, also their underlying material properties were investigated. For tavorite LiFeSO4F, different reaction pathways were identified by in operando XRD evaluation during charge and discharge. Furthermore, ligand involvement in the redox process was evaluated, and although most of the charge compensation was centered on the iron sites, the sulfate group also played a role in the oxidation of tavorite LiFeSO4F. In triplite LiFeSO4F and Li2FeP2O7, a redistribution of lithium and iron atoms was observed in the crystal structure during electrochemical cycling. For Li2FeP2O7, and increased randomization of metal ions occurred, which is similar to what has been reported for other iron phosphates and silicates. In contrast, triplite LiFeSO4F showed an increased ordering of lithium and iron atoms. An electrochemically induced ordering has previously not been reported upon electrochemical cycling for iron based Li-ion insertion materials, and was beneficial for the charge storage capacity of the material.
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El, Khalifi Mohammed. "Étude théorique des matériaux d'électrode positive négative pour batteries Li-ion." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20200.

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Ce mémoire est consacré à l'étude théorique des matériaux de cathode pour batteries Li-ion de structure olivine LiMPO4 (M=Mn, Fe, Co, Ni), des phases délithiées MPO4 et des phases mixtes LiFexMn1-xPO4, FexMn1-xPO4 et LiFexCo1-xPO4. La stabilité des phases magnétiques et les paramètres de maille théoriques ont été déterminés par la méthode des pseudopotentiels et comparés aux données expérimentales. Les structures électroniques ont été calculées par une méthode « tout électron » et analysées en termes d'hybridation des orbitales atomiques Ces résultats ont permis d'interpréter les spectres de photoélectrons X et d'absorption des rayons X, en particulier les modifications réversibles associées aux cycles de lithiation/délithiation. Les effets de la polarisation de spin et de la corrélation électronique ont été discutés. Enfin, le calcul des paramètres Mössbauer du 57Fe a montré qu'un accord quantitatif entre les résultats théoriques et les données expérimentales nécessitait la prise en compte de ces deux effets. Ce type de calcul a permis de prédire et d'expliquer que la transformation LiFePO4FePO4 s'accompagnait de la variation du gradient de champ électrique Vzz d'une extrémité à l'autre de l'échelle Mössbauer pour 57Fe
This thesis is devoted to the theoretical study of the cathode materials for Li-ion batteries with olivine structure LiMPO4 (M=Mn, Fe, Co, Ni), the delithiated phases MPO4 and the mixed phases LiFexMn1-xPO4, FexMn1-xPO4 and LiFexCo1-xPO4. The magnetic phase stability and lattice parameters were theoretically determined from pseudopotential calculations and the results have been compared with experiments. Electronic structures were obtained from all electron calculations and analyzed in terms of orbital hybridization. The results have been used for the interpretation of X-ray photoemission and X-ray absorption spectra, especially changes due to lithiation/delithiation cycles. Effects of spin polarization and electronic correlation on the electronic structures have been also discussed. It has been shown that ab initio calculations of the 57Fe Mössbauer parameters also require these two effects in order to obtain a quantitative agreement with experiments. Finally, it was found that LiFePO4FePO4 transformation involves a dramatic change of the electric field gradient VZZ from one end to the other of the 57Fe Mössbauer scale
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Webster, Simon. "An electrochemical study of lead acid battery positive electrodes." Thesis, Loughborough University, 1986. https://dspace.lboro.ac.uk/2134/13873.

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The thesis describes an electrochemical investigation into the properties of various lead alloys used in the manufacture of leadacid battery positive electrodes. The electrochemical results have been discussed in terms of current nucleation and growth theories. The morphological aspects of the discharge reaction have been investigated and theories are presented describing some of the important influences of various alloying ingredients. It has been found possible to suggest trends important in the optimisation of alloy composition for modern lead-acid battery grids. This aspect is especially relevant to the development of maintenance free technology.
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Books on the topic "Electrodes positives"

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McCalla, Eric. Consequences of Combinatorial Studies of Positive Electrodes for Li-ion Batteries. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05849-8.

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McCalla, Eric. Consequences of Combinatorial Studies of Positive Electrodes for Li-ion Batteries. Springer, 2016.

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Close, Frank. 1. The fly in the cathedral. Oxford University Press, 2015. http://dx.doi.org/10.1093/actrade/9780198718635.003.0001.

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‘The fly in the cathedral’ charts the discovery of the nuclear atom and the start of modern atomic and nuclear physics. It began in 1895 with the discovery of X-rays by Wilhelm Roentgen and radioactivity by Henri Becquerel. In 1897, J.J. Thomson discovered the electron and realised they were common to all atoms, which implied that atoms have an internal structure. Negatively-charged electrons are bound to positively-charged entities within the atom, but what carries this positive charge and how is it distributed? It was Ernest Rutherford, in 1911, who announced his solution: all of an atom’s positive charge and most of its mass are contained in a compact nucleus at the centre.
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Levin, Frank S. The Nuclear Atom. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198808275.003.0006.

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Chapter 5 describes how the concept of quantization (discretization) was first applied to atoms. This was done in 1913 by Niels Bohr, using Ernest Rutherford’s paradigm-changing, solar-system model of atomic structure, wherein the positively charged nucleus occupies a tiny central space, much smaller than the known sizes of atoms. Bohr, postulating a quantized version of this model for hydrogen, was able to explain previously inexplicable experimental features of that atom. He did so via an ad hoc quantization procedure that discretized the single electron’s energy, its angular momentum, and the radii of the orbits it could be in around the nucleus, formulas forwhich are presented, along with a diagram displaying the quantized energies. Despite this success, Bohr’s model failed not only for helium, with its two electrons, but for all other neutral atoms. It left some physicists hopeful, ready for whatever the next step might be.
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Appropriate electrode sites and electrical characteristics for TENS. Oxford University Press, 2014. http://dx.doi.org/10.1093/med/9780199673278.003.0004.

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The success of TENS treatment depends on the use of safe and appropriate TENS technique. Uncertainty about optimal TENS technique is due in part to the variety of possible electrode positions and electrical characteristics that can be chosen for treatment. Conventional TENS uses low-intensity, high-frequency currents to activate low-threshold afferent nerve fibres in the skin. AL-TENS uses high-intensity, low-frequency currents to generate non-painful phasic muscle contractions (twitching). The purpose of this chapter is to discuss the principles that underpin the use of safe and appropriate electrode sites and electrical characteristics during TENS. The chapter covers how to choose between conventional and AL-TENS, the appropriate electrode positioning for conventional TENS and AL-TENS including instances where AL-TENS may be more beneficial than conventional TENS, appropriate choice of electrical characteristics for stimulation, and biological, psychological, and social factors influencing response to TENS
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Publishing, Physics. Stay Positive Avoid Electrons: Dotted Bullet Notebook ~ Simple Physics Notebook for Daily Journal, Diary, and Gift. Independently Published, 2020.

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Pitt, Matthew. Results of the clinical application of SPACE in suspected disorders of the neuromuscular junction. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780198754596.003.0011.

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Findings in a large cohort of children with disorders of the neuromuscular junction are presented along with those in non-primary neuromuscular junction abnormalities. From these results it is possible to derive test parameters for stimulated potential analysis using concentric needle electrodes (SPACE) including sensitivity and specificity, along with positive and negative predictive values. The differences between performing stimulation techniques to determine jitter in children and adults are highlighted as are technical aspects and the effects of the differential diagnosis on interpretation of results. An investigative strategy is outlined to be used with SPACE. The chapter concludes with discussion of the occurrence of normal jitter measurements with SPACE in proven cases of myasthenia as well as the phenomenon of delayed diagnosis of myasthenia and its relationship to the availability of neurophysiological testing.
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Lo, Meng-chen, Marie-France Marin, Alik S. Widge, and Mohammed R. Milad. Device-Based Treatment for PTSD. Edited by Frederick J. Stoddard, David M. Benedek, Mohammed R. Milad, and Robert J. Ursano. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190457136.003.0025.

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Device-based neuromodulation is an emerging tool with great potential for significant scientific and clinical implications for a number of mental disorders. Neuromodulation techniques deliver electro-magnetic pulses into the brain via invasive or noninvasive electrodes, with various timing and stimulation parameters. The stimulation is thought to work as a “brain pacemaker” that either activates or inactivates targeted brain regions to restore normal homeostasis. There have been significant recent efforts to explore the clinical utility of device-based approaches for the treatment of mood, anxiety disorders, and to a limited extent posttraumatic stress disorder (PTSD). This chapter outlines the scientific underpinnings and rationale for various device-based treatments of PTSD, highlights positive results of studies in other mental disorders, and summarizes the limited clinical data related specifically to the treatment of PTSD and other trauma- and stressor-related disorders to date.
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Fowler, Clare J., and Jalesh N. Panicker. Urinary retention in women. Edited by Christopher R. Chapple. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199659579.003.0044.

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If a young woman in complete urinary retention is investigated and all urological and neurological investigations are found to be normal, the commonest diagnosis then made is Fowler’s syndrome (FS). Described by Fowler et al. in 1987, the original syndrome comprised of complete urinary retention with the finding of a particular pattern of electromyographic (EMG) activity recorded with a concentric needle electrode from the striated urethral sphincter, in a young woman with clinical features of polycystic ovaries. Prior to that, description medical opinion was that urinary retention in young women was due to ‘hysteria’; more had been written about ‘psychogenic urinary retention in women’ than any other possible causes. Twenty-five years on, the situation now seems to be that if neither the urologist or urologist can discover an underlying abnormality, the woman may be told she has FS without any positive identification of that condition.
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Schomer, Donald L., Charles M. Epstein, Susan T. Herman, Douglas Maus, and Bruce J. Fisch. Recording Principles. Edited by Donald L. Schomer and Fernando H. Lopes da Silva. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190228484.003.0005.

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This chapter reviews the technical aspects of recording and reviewing clinical electroencephalograms (EEGs) and related biopotentials. While advances in engineering technology have revolutionized EEG machines, the basic principles underlying accurate representation of brain activity are largely unchanged. The first section reviews the analog EEG components, and the second section discusses analog-to-digital conversion, digital filters, and display and storage parameters. Digital EEG machines are now less expensive and their capabilities far surpass those of analog machines. The third section reviews how electrode positions and systems of signal display (montages) can be used to determine the polarity and field of EEG signals. The final section describes how other biopotentials are acquired and displayed. Polygraphy can provide crucial information on other physiological processes that can impact EEG activity and can help identify potential artifactual signals. We highlight recent advances that allow the recording of a broader range of EEG frequencies and spatial distribution.
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Book chapters on the topic "Electrodes positives"

1

Monconduit, Laure, Laurence Croguennec, and Rémi Dedryvère. "Positive Electrodes." In Electrodes for Li-Ion Batteries, 29–62. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2015. http://dx.doi.org/10.1002/9781119007364.ch2.

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Huggins, Robert A. "Positive Electrodes in Lithium Systems." In Energy Storage, 391–426. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-21239-5_21.

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Huggins, Robert A. "Positive Electrodes in Lithium Systems." In Energy Storage, 319–53. Boston, MA: Springer US, 2010. http://dx.doi.org/10.1007/978-1-4419-1024-0_19.

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Machida, Nobuya, and Akitoshi Hayashi. "Sulfur and Sulfide Positive Electrode." In Next Generation Batteries, 125–35. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-6668-8_12.

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Huggins, Robert A. "Positive Electrodes in Other Aqueous Systems." In Energy Storage, 339–60. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-21239-5_19.

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Huggins, Robert A. "Positive Electrodes in Other Aqueous Systems." In Energy Storage, 267–89. Boston, MA: Springer US, 2010. http://dx.doi.org/10.1007/978-1-4419-1024-0_17.

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Yamamoto*, Haruhisa, and Hidekazu Mori. "SBR Binder (for Negative Electrode) and ACM Binder (for Positive Electrode)." In Lithium-Ion Batteries, 1–17. New York, NY: Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-34445-4_7.

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Tatsumi, Kuniaki. "Nano Aspects of Advanced Positive Electrodes for Lithium-Ion Batteries." In Nanoscale Technology for Advanced Lithium Batteries, 23–30. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-8675-6_3.

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Fuhrmann, Jürgen, Leo Nick, and Günter H. Scherer. "Deformation Induced Emission of Electrons and Positive Ions." In Integration of Fundamental Polymer Science and Technology—3, 367–80. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-1115-4_47.

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Imai, Hiroaki. "Synthesis of Structured Spinel Oxide Positive Electrodes to Improve Electrochemical Performance." In Next Generation Batteries, 515–20. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-6668-8_45.

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Conference papers on the topic "Electrodes positives"

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Miller, Tiffany E., and Eniko T. Enikov. "Electric Field-Assisted Assembly of Type-I Collagen for Applications in Biomedical Micro-Systems." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-82930.

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In the field of nanotechnology and applied engineering, an area that has received a great deal of attention is that of nanoassembly. The objective of this study was to demonstrate nanoassembly of type-I collagen on specified surfaces in response to an electric field. Two, otherwise identical, collagen solutions were prepared and adjusted to pHs of 5.5 and 8. The isoelectric fosusing point of collagen occurs at pH=6.7 which implies that the suspended collagen fibers in the aforementioned solutions possessed a net positive or negative charge, respectively. In each collagen solution, one volt was applied through a set of submerged electrodes for one minute. Atomic force microscopy was used to detect if and where assembly had occurred on the electrodes. The positively charged fibrils (pH=5.5) assembled on the negative electrode, but not on the positive electrode. The negatively charged fibrils (pH=8) assembled only on the positive electrode, but not on the negative electrode. In both cases, assembly occurred on the electrode of opposite charge of the suspended collagen fibrils, which was anticipated. The assembly of the positively charged fibrils (pH=5.5) on the cathode produced larger fibers than the fibers that were produced by the negatively charged fibrils (pH=8) on the anode. This indicated the more favorable environment for nanoassembly was the positively charged fibril solution (pH=5.5).
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Boyer, Richard B., Pramode Chiruvolu, Arun Jose, Joshua Liu, Adam Sifuentes, Allison Connolly, Britni Crocker, and Peter Stempriewica. "Enhancing SVT Discrimination in Implantable Cardioverter Defibrillators Using MEMS Accelerometers." In ASME 2007 2nd Frontiers in Biomedical Devices Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/biomed2007-38056.

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Sudden cardiac death (SCD) accounts for over 325,000 deaths in the United States per year. Implantable cardioverter defibrillators (ICDs), about 100,000 of which are implanted each year, are used to diagnose and treat cardiac arrhythmias in patients that are at risk for sudden cardiac death due to ventricular fibrillation. Upon detection of an arrhythmia, the ICD has several treatment options, all of which deliver varied amounts of electric current to the myocardium. Detection of ventricular tachycardia (VT) or ventricular fibrillation (VF) prompts the ICD to administer high-energy defibrillation shocks, which can exceed 30J. The current method for sensing arrhythmias is the use of electrodes implanted in the myocardium which are capable of detecting electric potentials. The extensively studied algorithms that analyze electrogram sensor data have allowed ICD’s to achieve a 0% false negative rate for detection of fibrillation. The drawback, however, is the high false positive rate of over 22%. False positives result in inappropriate shocks which have detrimental effects on patient health and quality of life [1].
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Chen, Yun, and Souran Manoochehri. "Optimal Design of Electrode Structure and Microfluidics Channel for Effective Particle Separations." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-63346.

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This paper presents the optimal design of electrode structure and microfluidics channel for effective particle separations. The purpose of the microfluidics chip is to generate the DEP (dielectrophoresis) force within the micro channel to separate both negative DEP (nDEP) and positive DEP (pDEP) particles of same sizes. The particles will experience DEP force when passing through the electric field created by electrode arrays located in different positions within the channel. The channel contains several electrode arrays where the pDEP particles are moved away from the electrodes and the nDEP particles are attracted towards them. In some existing microfluidics chips, because of the high intensity of the electric field around the electrodes, which results in a very high DEP force near the electrodes, most of the positive DEP particles are captured in the space between electrodes without being guided to the target outlet. Moreover, the effective area of DEP force is limited to a small region near the corner of the electrodes, therefore only those particles very close to the electrodes will experience sufficient attractive forces to be guided towards the target locations. This will decrease the efficiency of the particle separation. In this study, we developed an optimization methodology for design of electrode configurations using numerical modeling. The optimized electrode structure can provide much more evenly distributed DEP field. The design of the channel, the number and position of the electrode arrays were optimized in order to improve the efficiency of the particle separation. Finally, the optimized electrode structure and microfluidics channel were modeled and tested using multiphysics simulation software and the results show that this optimized design of microfluidics channel can provide high throughput and more effectiveness for particle separation compared to many existing microfluidics devices.
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Banerjee, Soumik, Sohail Murad, and Ishwar K. Puri. "Carbon Nanotubes as Nano-Pumps: A Molecular Dynamics Investigation." In ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2006. http://dx.doi.org/10.1115/icnmm2006-96206.

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This paper focuses on the use of carbon nanotubes (CNT) for ion separation and encapsulation from a solution containing both positive and negatively charged ions. Metal ion separation from drinking water or during material processing applications can be an important issue. We use molecular dynamics simulations to demonstrate that a pair of carbon nanotubes with patterned positive and negative charges can form the basis of an effective device for the separation or encapsulation of ions. We consider three different charge patterns: i) Electrodes, where all the atoms of a CNT are charged with a finite surface charge density; ii) Alternate axial bands of positive and negative charges on each electrode; and iii) Alternate circumferential rings of positive and negative charges on the electrodes. The charge pattern determines the preferential intake of water and/or ions by a nanotube. As conventional electrodes they adsorb ions, but with an alternate band or ring charge pattern they adsorb the water molecules. Our simulations show that a charged CNT can be used as a nano-pump that provides purified water or ions from an impure solution.
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Li, Lei, Xiaoli Xiang, Lin Gu, and Wansheng Zhao. "Rapid-Tooling of Bunched Electrode for EDM." In ASME 2011 International Manufacturing Science and Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/msec2011-50105.

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A bunched electrode for Electrical Discharge Machining (EDM) is formed by bunching numerous cell electrodes as a whole and allows better flushing to facilitate removal of more heat and debris produced during machining. This paper proposes a rapid tooling method for preparing bunched electrodes with desired end-face. A specially designed apparatus, which sits on an XY worktable of a CNC machine tool, is employed to hold the pre-bunched with flat end-face. By using a protrusion pin which is fixed on Z-axis, the heights of each cell electrode are protruded one after another according to a CNC program, which is generated by CAD/CAM software. The end-face of the bunched electrode approximates the ideal end-face of the designed 3D model by adjusting the Z positions of each cell electrode. By using this method the cost and time for electrode preparation are dramatically reduced as compared to that made by traditional cutting method. An investigation on 3D cavity machining of bunched electrode was conducted. The result gives a solid verification of the feasibility of using bunched electrode into roughing process of EDM.
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K. Mohammadian, Shahabeddin, and Yuwen Zhang. "Flowing Electrolyte As Coolant Inside the Microgrooves Embedded in the Electrodes: A Novel Thermal Management of Li-Ion Batteries." In ASME 2019 Heat Transfer Summer Conference collocated with the ASME 2019 13th International Conference on Energy Sustainability. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/ht2019-3664.

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Abstract One way to enhance thermal performance of the Li-ion batteries is embedding microgrooves inside the porous electrodes and flowing the electrolyte through these microgrooves. A 2D thermal Lattice Boltzmann Method (LBM) was employed to predict electrolyte flow, heat transfer, and internal heat generation inside the positive porous electrode. Size and number of the microgrooves were investigated, and it was found that embedding microgrooves inside the porous electrode improved the thermal performance of the Li-ion battery by keeping the electrode in lower temperatures and improving its temperature uniformity. Furthermore, increasing the number of microgrooves (in a constant ratio between total size of the microgrooves to size of the porous electrode) kept the porous electrode in lower temperatures and enhanced temperature uniformity.
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Lynch, Corey M., Mehdi Khodayari, Alex A. Volinsky, and Nathan B. Crane. "Demonstration of Continuous Electrowetting Actuation." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-40060.

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Electrowetting is the change in apparent surface energy of a liquid in an applied electric field. It has shown great promise in diverse applications including lab-on-a-chip and electronic displays. The electrowetting response is typically considered independent of the actuation voltage polarity. This paper describes a new approach that achiees actuation in different directions for positive and negative voltage polarities using the electrochemical characteristics of aluminum electrodes. This paper presents a concept for continuous actuation of a droplet using a single electrode and DC voltage based on this effect. Initial experiments demonstrate that droplet motion is possible. Measurements of voltage drop across aluminum electrodes confirms the polarity-dependent response of the electrodes.
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Uehara, Satoshi, Naoya Yukimoto, Hirofumi Shintaku, and Satoyuki Kawano. "Experimental Study on Flow Control of λDNA in Electrode-Embedded Microchannel." In ASME-JSME-KSME 2011 Joint Fluids Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajk2011-36039.

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In this paper, we report the experimental study on novel DNA separation using electrode-embedded microchannel. A microchannel with an interdigitated electrode on the wall was developed for investigation. The experiment was carried out with flowing solution including λDNA by pressure driven flow. DC voltage of ∼2 V was applied to the interdigitated electrode. Under the ideal condition, λDNA is trapped on electrode and released from it stochastically. From the observation, it was found that the velocity of λDNA was decreased by the electric field when it approached to a positive electrode. Furthermore, we theoretically estimated the trajectory of flowing λDNA in the microchannel. Comparing the experimental and theoretical results, it was found that the electric field by the interdigitated electrodes was shielded by electrolyte in the solution.
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Chen, Yun, and Souran Manoochehri. "Optimization of Electrode Structure for Effective Particle Separation in a Micro-Fluidic Chip." In ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/detc2013-13288.

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This paper presents the optimization of electrode structure for effective particle separation in a micro fluidic chip. The purpose of electrodes in the micro fluidic chip is to generate the DEP (dielectrophoresis) force that is perpendicular to the micro channel direction to separate both nDEP and pDEP particles of the same sizes. The particles will experience DEP force when passing through the electric field which is created by electrode arrays located in different positions in the channel. In this study, we optimize the electrode structure by investigating different shapes and dimensions using numerical simulation and modeling. The optimized electrode structure can provide better separation effect due to larger effective area of DEP force and relative small variation of electric field gradient as demonstrated in this study.
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Jang, Jaesung, Demir Akin, Kwan Seop Lim, Michael R. Ladisch, and Rashid Bashir. "Electrostatic Capture of Airborne Nanoparticles in Swirling Flows for Bio-MEMS Applications." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-15411.

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Abstract:
Motivated by capture and detection of airborne biological agents in real time, we present the electrostatic capture of 100nm diameter polystyrene nanoparticles as a model system under swirling gas flows in a homemade particle collector having the forward outlet. The particle collector has five small positive electrodes on the bottom and one large grounded electrode on the top. The particles coming into the collector are slowed down during their swirling and stay in the collector before leaving. Particles captured on the center electrode of this collector were much less than those on the surrounding four electrodes and 10 - 25% of the particles with negative charges entering this collector were captured on the bottom electrodes at a flow rate of 1.1 l/min and an applied potential of 2 kV. Using a commercial CFD code FLUENT, we simulated the effects of the different types of collector outlet configurations and flow rates on the particles' trajectories, velocities, and travel times inside the collector. We also present the highest particle capture position inside the collector in those different configurations. The forward outlet configuration is the most favorable to particle capture among the tested configurations in terms of particles' minimum achievable velocities and their travel times at a flow rate of 1.1 l/min. This collector is well adaptable to integration with micro resonator devices and can be used for real-time monitoring of bioaerosols.
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Reports on the topic "Electrodes positives"

1

Hudak, Nicholas S. Rechargeable aluminum batteries with conducting polymers as positive electrodes. Office of Scientific and Technical Information (OSTI), December 2013. http://dx.doi.org/10.2172/1121960.

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2

Zimmerman, Albert H. Nickel Hydrogen Cell Positive-Electrode Studies: Cobalt Segregation in Reducing Environments,. Fort Belvoir, VA: Defense Technical Information Center, May 1987. http://dx.doi.org/10.21236/ada193025.

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3

Wilcox, James Douglas. Studies on two classes of positive electrode materials for lithium-ion batteries. Office of Scientific and Technical Information (OSTI), December 2008. http://dx.doi.org/10.2172/983034.

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4

Alexeff, Igor. Millimeter Microwave Emission by Use of Plasma Produced Electrons Orbiting a Positively-Charged Wire. Fort Belvoir, VA: Defense Technical Information Center, March 1986. http://dx.doi.org/10.21236/ada196005.

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