1,720,964 research outputs found
Dataset for Current distribution in a rectangular flow channel manufactured by 3D-printing
No full textThe characterization and improvement of a rectangular channel electrolyte flow compartment used in an iron-air flow battery was carried out by using an arrangement of copper electrodes to measure the current density distribution employing the limiting current technique. The present work addresses the hydrodynamics and mass transport distribution in the compartment and their improvement by an improved electrolyte compartment that results in a more uniform current distribution. The current distribution was evaluated as the ratio between the local and the averaged limiting current densities during the reduction of copper ions over a range of mean linear flow velocity across the electrode surface (2-30 cm s-1).
The initial compartment, showed larger differences between the minimum and maximum currents than the electrolyte compartment that resulted as part of the design process and showed a higher pressure drop at a given mean linear flow velocity.
This data supports the publication:
Figueredo Rodriguez, Horacio, Mckerracher, Rachel, Ponce De Leon Albarran, Carlos and Walsh, Frank (2016) Current distribution in a rectangular flow channel manufactured by 3D-printing. AIChE Journal , 1-35. (doi:10.1002/aic.15454).</span
Batteries – Battery Types – Iron Batteries | Iron-Air
No full textSecond Edition.--This is an update of M. Egashira, SECONDARY BATTERIES – METAL-AIR SYSTEMS | Iron–Air (Secondary and Primary), Editor(s): Jürgen Garche, Encyclopedia of Electrochemical Power Sources, Elsevier, 2009, Pages 372–375, ISBN 9780444527455, https://doi.org/10.1016/B978-044452745-5.00102-7.Iron–air batteries have been proposed and developed for use as rechargeable stationary power storage or as batteries for automotive applications. The iron-air system has a high theoretical specific energy close to 1200 Wh kg−1, because the air for the cathode can be extracted from the environment rather than being stored inside the battery. However, the achievable specific energy has been around an order of magnitude lower. This is mainly caused by parasitic reactions such as hydrogen evolution, and the large overpotentials at the air cathode caused by slow electrochemical reaction kinetics. In this article, the history of the iron-air battery is outlined, followed by a description of the construction of the battery, and the current state of research into its uses.Peer reviewe
Electrochemically treated TiO<sub>2</sub> for enhanced performance in aqueous Al-ion batteries
No full textThe potential for low cost, environmentally friendly and high rate energy storage has led to the study of anatase-TiO2 as an electrode material in aqueous Al3+ electrolytes. This paper describes the improved performance from an electrochemically treated composite TiO2 electrode for use in aqueous Al-ion batteries. After application of the cathodic electrochemical treatment in 1 mol/dm3 KOH, Mott-Schottky analysis showed the treated electrode as having an increased electron density and an altered open circuit potential, which remained stable throughout cycling. The cathodic treatment also resulted in a change in colour of TiO2. Treated-TiO2 demonstrated improved capacity, coulombic efficiency and stability when galvanostatically cycled in 1 mol·dm-3AlCl3/1 mol·dm-3 KCl. A treated-TiO2 electrode produced a capacity of 15.3 mA·h·g-1 with 99.95% coulombic efficiency at the high specific current of 10 A/g. Additionally, X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy were employed to elucidate the origin of this improved performance.</p
A review of the iron–air secondary battery for energy storage
No full textRecent interest in the iron–air flow battery, known since the 1970s, has been driven by incentives to develop low-cost, environmentally friendly and robust rechargeable batteries. With a predicted open-circuit potential of 1.28?V, specific charge capacity of <300?A?h?kg?1 and reported efficiencies of 96, 40 and 35?% for charge, voltage and energy, respectively, the iron–air system could be well suited for a range of applications, including automotive. A number of challenges still need to be resolved, including: efficient and moderate-cost bifunctional oxygen electrodes, low-cost iron electrodes able to decrease corrosion and hydrogen evolution, new cell designs using additive manufacturing technologies and mathematical models to improve battery performance. This Mini review considers the thermodynamics and kinetics aspects of the iron–air battery, the operational variables and cell components, thereby highlighting current challenges and assessing recent developments
Current distribution in a rectangular flow channel manufactured by 3D-printing
No full textThe characterization and improvement of a rectangular channel electrolyte flow compartment used in an iron-air flow battery was carried out by using an arrangement of copper electrodes to measure the current density distribution employing the limiting current technique. The present work addresses the hydrodynamics and mass transport distribution in the compartment and their improvement by an improved electrolyte compartment that results in a more uniform current distribution. The current distribution was evaluated as the ratio between the local and the averaged limiting current densities during the reduction of copper ions over a range of mean linear flow velocity across the electrode surface (2-30 cm s-1). The initial compartment, showed larger differences between the minimum and maximum currents than the electrolyte compartment that resulted as part of the design process and showed a higher pressure drop at a given mean linear flow velocity
Advances in prevention of thermal runaway in lithium-ion batteries
No full textThe prevention of thermal runaway (TR) in lithium‐ion batteries is vital as the technology is pushed to its limit of power and energy delivery in applications such as electric vehicles. TR and the resulting fire and explosion have been responsible for several high‐profile accidents and product recalls over the past decade. Herein, the causes of TR are described and novel preventative methods are examined, approaching the problem from different angles by altering the internal structure of the battery to undergo thermal shutdown or developing the battery and thermal management systems so that they can detect and prevent TR. Ultimately, a variety of different technologies is needed to address the emerging market of highly specialized lithium‐ion batteries. Key innovations discussed include positive temperature coefficient (PTC) materials, self‐healing polymer electrolytes, and hybrid liquid–solid‐state electrolytes. Mist cooling achieves a highly uniform temperature inside the battery pack without the need for pumps to circulate a coolant. The development of battery management systems (BMSs) which model the internal temperature of the cell from real‐time data and prevent the cell reaching a critical temperature is an essential area for further research
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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