Chemisorption as the essential step in electrochemical energy conversion

Growing world population and energy demands have placed energy conversion and storage into the very centre of modern research. Electrochemical energy conversion systems including batteries, fuel cells, and supercapacitors, are widely considered as the next generation power sources. Even though they rely on different mechanisms of energy conversion and storage, fundamentally these are all electrochemical cells, operating through processes taking place at the solid/liquid interfaces, i.e. electrodes. Considering the interfacial nature of electrodes, it is clear that adsorption phenomena cannot be neglected when considering electrochemical systems. More than that, they are of crucial importance for electrochemical processes and represent an essential step in electrochemical energy conversion. In this contribution we give an overview of the phenomena underlying the operation of sustainable metal-ion batteries, fuel cells and supercapacitors, ranging from electrocatalytic reactions and pseudo-faradaic processes to purely adsorptive processes, emphasizing the types, roles and significance of chemisorption. We review experimental and theoretical methods which can provide information about chemisorption in the mentioned systems, stressing the importance of combining both approaches

Assessment of commercially available and experimental hydrogen electrodes

NASA Lewis Research Center is currently involved in advanced cell component development for nickel-hydrogen cells and batteries. Long life, high energy density, improved performance and reliability are required for energy storage systems in future space missions. Commercially available as well as experimental hydrogen electrodes were assessed and copared to the state-of-the-art hydrogen electrode that is currently being used in nickel-hydrogen batteries. These electrodes were evaluated by scanning electron microscopy and standard electrochemical polarization measurements. Production variables such as Teflon content and platinum catalyst loading were considered in order to assess various hydrogen electrods with regard to the different electrode manufacturing processes

Recent advances in carbon-based nanomaterials for multivalent-ion hybrid capacitors: a review

Hybrid capacitors are emerging because of their ability to store large amounts of energy, cycle through charges quickly, and maintain stability even in harsh environments or at extreme temperatures. Hybrid capacitors with monovalent cations such as Li+, Na+, and K+ have been extensively studied. However, the flammable nature of organic electrolytes and the reactive alkali metallic electrodes have raised safety concerns. This has prompted the development of novel aqueous multivalent cation storage systems, which can provide several benefits, including high capacity and energy density, rapid charge transfer, and low cost. With these advantages and the energy storage properties, multivalent cations such as Zn2+, Mg2+, Ca2+, and Al3+ have been applied to multivalent-ion hybrid capacitors (MIHCs), and the latest developments and design ideas for these have been recently reviewed. However, an overview from the perspective of materials with unique advantages and experimental designs remains limited. Carbon-based nanomaterials are leading candidates for next-generation energy storage devices due to their outstanding properties in MIHCs. The use of carbon-based nanomaterials is attractive because these materials are inexpensive, scalable, safe, and non-toxic. They are also bioactive at the anode interface, allowing them to promote electrochemical reactions with redox species that would otherwise not take place. This paper reviews recent advances in MIHCs and related carbon-based materials and discusses the utilization of carbon materials in MIHCs and ideas for material design, electrochemical behavior, energy storage mechanisms, electrode design, and future research prospects. Based on the integration of related challenges and development, we aim to provide insights and commercialization reference for laboratory research. For the first time, combined with global intellectual property analysis, this paper summarizes the current main research institutions and enterprises of various hybrid capacitors, and provides important technical competition information and development trends for researchers and practitioners in the field of energy storage. Simultaneously, we provide a perspective for the development of MIHCs, a description of the existing research, and guidelines for the design, production, commercialization, and advancement of unique high-performance electrochemical energy storage devices

Smart LiFePO4 battery modules in a fast charge application for local public transportation

This paper describes the research effort jointly carried out by the University of Pisa and ENEA on electrochemical energy storage systems based on Lithium-ion batteries, particularly the Lithium-Iron-Phosphate cells. In more detail, the paper first illustrates the design and experimental characterization of a family of 12 V modules, each of them provided with an electronic management system, to be used for electric traction. Then, the sizing of the energy storage system for an electric bus providing a service with 'fast and frequent' charge phases is described

Investigation of the Electrochemical Properties of CoAl-Layered Double Hydroxide/Ni(OH)2

Layered double hydroxides (LDH) as active electrode materials have become the focus of research in energy storage applications. The manufacturing of excellent electrochemical performance of the LDH electrode is still a challenge. In this paper, the production of CoAl-LDH@Ni(OH)2 is carried out in two steps, including hydrothermal and electrodeposition techniques. The prominent features of this electrode material are shown in the structural and morphological aspects, and the electrochemical properties are investigated by improving the conductivity and cycle stability. The core of this experimental study is to investigate the properties of the materials by depositing different amounts of nickel hydroxide and changing the loading of the active materials. The experimental results show that the specific capacity is 1810.5F·g−1 at 2 A/g current density and the cycle stability remained at 76% at 30 A g−1 for 3000 cycles. Moreover, a solid-state asymmetric supercapacitor with CoAl-LDH@Ni(OH)2 as the positive electrode and multi-walled carbon nanotube coated on the nickel foam as the negative electrode delivers high energy density (16.72 Wh kg−1 at the power density of 350.01 W kg−1). This study indicates the advantages of the design and synthesis of layered double hydroxides, a composite with excellent electrochemical properties that has potential applications in energy storage

Electrochemical Cell Design and Experimental Setup for Passive Two-Phase Cooling

The goal for the three credit-hour independent study in the Nanoscale Energy and Interfacial Transport laboratory was to familiarize myself with research methodology, energy storage on the micrometer scale, passive cooling for advanced electronics, and provide general aid in setting up the new laboratory space. Dr. Damena Agonafer, the principal investigator, assigned two projects to undergraduate researchers from the months of January 2017 to May 2017: novel methods for increased nanocapacitor performance, and passive two-phase cooling for microelectronics. Initial work consisted of background research into hybrid nanocapacitors, including materials, ordered quasi 2-D structures, and synthesis methods. This project was cancelled in progress in favor of the cooling project. After transitioning projects, work primarily consisted of designing and prototyping an electrolyte cell for synthesizing the required micro-structures, modeling experimental setups in 3-D CAD software, and continuing to construct the laboratory. The outcomes of this independent study include a deep understanding of electrochemical energy storage and transfer and research methodology, a functional design for an electrochemical cell for synthesis of a copper inverse-opal structure, and a nearly complete physical laboratory space

The Joint Center for Energy Storage Research: A New Paradigm for Battery Research and Development

The Joint Center for Energy Storage Research (JCESR) seeks transformational change in transportation and the electricity grid driven by next generation high performance, low cost electricity storage. To pursue this transformative vision JCESR introduces a new paradigm for battery research: integrating discovery science, battery design, research prototyping and manufacturing collaboration in a single highly interactive organization. This new paradigm will accelerate the pace of discovery and innovation and reduce the time from conceptualization to commercialization. JCESR applies its new paradigm exclusively to beyond-lithium-ion batteries, a vast, rich and largely unexplored frontier. This review presents JCESR's motivation, vision, mission, intended outcomes or legacies and first year accomplishments.Comment: 17 pages, 14 figures, 96 reference

Bidirectional Boost/Buck Quadratic Converter for Distributed Generation Systems with Electrochemical Storage Systems

Trabalho apresentado no 5th IEEE International Conference on Renewable Energy Research and Applications, 20-23 de novembro 2016, Birmingham, Reino UnidoThe increasing number of distributed generation systems using renewable and non-conventional energy sources show the trend of future generation systems. Most of these systems require power electronic converters as an interface between the DC voltage buses and electrochemical storage systems. Such storage systems, like batteries or supercapacitors, usually need bidirectional DC-DC converters to allow their charge or discharge according with necessary operation conditions. In this paper, a non-isolated bidirectional Buck-Boost converter with high voltage gain for electrochemical storage devices used in distributed generation systems is presented. To achieve high voltage gain ratios, the proposed topology presents quadratic characteristics in both step-down (Buck) and step-up (Boost) operation modes. In addition to the wide conversion range, it presents continuous input and output current, reduced charging/discharging ripple and simple control circuitry. All these features allow the energy exchange smoothly and continuously resulting in a longer durability of storage devices. The principle of the operation of the proposed converter in both operation modes, as well as their theoretical analysis will be discussed. The performance of this bidirectional power converter is confirmed through simulation and experimental results.N/