Charging a Li–O2 battery using a redox mediator
TL;DR: This work shows that incorporation of a redox mediator, tetrathiafulvalene (TTF), enables recharging at rates that are impossible for the cell in the absence of the mediator.
Abstract: The non-aqueous Li-air (O2) battery is receiving intense interest because its theoretical specific energy exceeds that of Li-ion batteries. Recharging the Li-O2 battery depends on oxidizing solid lithium peroxide (Li2O2), which is formed on discharge within the porous cathode. However, transporting charge between Li2O2 particles and the solid electrode surface is at best very difficult and leads to voltage polarization on charging, even at modest rates. This is a significant problem facing the non-aqueous Li-O2 battery. Here we show that incorporation of a redox mediator, tetrathiafulvalene (TTF), enables recharging at rates that are impossible for the cell in the absence of the mediator. On charging, TTF is oxidized to TTF(+) at the cathode surface; TTF(+) in turn oxidizes the solid Li2O2, which results in the regeneration of TTF. The mediator acts as an electron-hole transfer agent that permits efficient oxidation of solid Li2O2. The cell with the mediator demonstrated 100 charge/discharge cycles.
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3,536 citations
TL;DR: A review of post-lithium-ion batteries is presented in this paper with a focus on their operating principles, advantages and the challenges that they face, and the volumetric energy density of each battery is examined using a commercial pouch-cell configuration.
Abstract: Energy density is the main property of rechargeable batteries that has driven the entire technology forward in past decades. Lithium-ion batteries (LIBs) now surpass other, previously competitive battery types (for example, lead–acid and nickel metal hydride) but still require extensive further improvement to, in particular, extend the operation hours of mobile IT devices and the driving mileages of all-electric vehicles. In this Review, we present a critical overview of a wide range of post-LIB materials and systems that could have a pivotal role in meeting such demands. We divide battery systems into two categories: near-term and long-term technologies. To provide a realistic and balanced perspective, we describe the operating principles and remaining issues of each post-LIB technology, and also evaluate these materials under commercial cell configurations. Post-lithium-ion batteries are reviewed with a focus on their operating principles, advantages and the challenges that they face. The volumetric energy density of each battery is examined using a commercial pouch-cell configuration to evaluate its practical significance and identify appropriate research directions.
3,314 citations
TL;DR: Various application of ILs are reviewed by focusing on their use as electrolyte materials for Li/Na ion batteries, Li-sulfur batteries,Li-oxygen batteries, and nonhumidifiedfuel cells and as carbon precursors for electrode catalysts of fuel cells and electrode materials for batteries and supercapacitors.
Abstract: Ionic liquids (ILs) are liquids consisting entirely of ions and can be further defined as molten salts having melting points lower than 100 °C. One of the most important research areas for IL utilization is undoubtedly their energy application, especially for energy storage and conversion materials and devices, because there is a continuously increasing demand for clean and sustainable energy. In this article, various application of ILs are reviewed by focusing on their use as electrolyte materials for Li/Na ion batteries, Li-sulfur batteries, Li-oxygen batteries, and nonhumidified fuel cells and as carbon precursors for electrode catalysts of fuel cells and electrode materials for batteries and supercapacitors. Due to their characteristic properties such as nonvolatility, high thermal stability, and high ionic conductivity, ILs appear to meet the rigorous demands/criteria of these various applications. However, for further development, specific applications for which these characteristic properties becom...
1,096 citations
TL;DR: A review of recent advances in understanding the chemistry and electrochemistry that govern the operation of the lithium-air battery, especially the reactions at the cathode, is presented in this paper.
Abstract: The rechargeable lithium–air battery has the highest theoretical specific energy of any rechargeable battery and could transform energy storage if a practical device could be realized. At the fundamental level, little was known about the reactions and processes that take place in the battery, representing a significant barrier to progress. Here, we review recent advances in understanding the chemistry and electrochemistry that govern the operation of the lithium–air battery, especially the reactions at the cathode. The mechanisms of O2 reduction to Li2O2 on discharge and the reverse process on charge are discussed in detail, as are their consequences for the rate and capacity of the battery. The various parasitic reactions involving the cathode and electrolyte during discharge and charge are also considered. We also provide views on understanding the stability of the cathode and electrolyte and examine design principles for better lithium–air batteries. Lithium–air batteries offer great promise for high-energy storage capability but also pose tremendous challenges for their realization. This Review surveys recent advances in understanding the fundamental science that governs lithium–air battery operation, focusing on the reactions at the oxygen electrode.
962 citations
TL;DR: Li−O2 Batteries Jun Lu,† Li Li,‡ Jin-Bum Park, Yang-Kook Sun,* Feng Wu,*,‡ and Khalil Amine*,†,∥Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439.
Abstract: Li−O2 Batteries Jun Lu,† Li Li,‡ Jin-Bum Park, Yang-Kook Sun,* Feng Wu,*,‡ and Khalil Amine*,†,∥ †Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States ‡Beijing Key Laboratory of Environmental Science and Engineering, School of Chemical Engineering and the Environment, Beijing Institute of Technology, Beijing 100081, China Department of Energy Engineering, Hanyang University, Seoul 133-791, South Korea Chemistry Department, Faculty of Science, King Abdulaziz University, 80203 Jeddah, Saudi Arabia
941 citations
References
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01 Jan 1980
TL;DR: In this paper, the authors present a comprehensive overview of electrode processes and their application in the field of chemical simulation, including potential sweep and potential sweep methods, coupled homogeneous chemical reactions, double-layer structure and adsorption.
Abstract: Major Symbols. Standard Abbreviations. Introduction and Overview of Electrode Processes. Potentials and Thermodynamics of Cells. Kinetics of Electrode Reactions. Mass Transfer by Migration and Diffusion. Basic Potential Step Methods. Potential Sweep Methods. Polarography and Pulse Voltammetry. Controlled--Current Techniques. Method Involving Forced Convention--Hydrodynamic Methods. Techniques Based on Concepts of Impedance. Bulk Electrolysis Methods. Electrode Reactions with Coupled Homogeneous Chemical Reactions. Double--Layer Structure and Adsorption. Electroactive Layers and Modified Electrodes. Electrochemical Instrumentation. Scanning Probe Techniques. Spectroelectrochemistry and Other Coupled Characterization Methods. Photoelectrochemistry and Electrogenerated Chemiluminescence. Appendix A: Mathematical Methods. Appendix B: Digital Simulations of Electrochemical Problems. Appendix C: Reference Tables. Index.
20,533 citations
TL;DR: The energy that can be stored in Li-air and Li-S cells is compared with Li-ion; the operation of the cells is discussed, as are the significant hurdles that will have to be overcome if such batteries are to succeed.
Abstract: Li-ion batteries have transformed portable electronics and will play a key role in the electrification of transport. However, the highest energy storage possible for Li-ion batteries is insufficient for the long-term needs of society, for example, extended-range electric vehicles. To go beyond the horizon of Li-ion batteries is a formidable challenge; there are few options. Here we consider two: Li-air (O(2)) and Li-S. The energy that can be stored in Li-air (based on aqueous or non-aqueous electrolytes) and Li-S cells is compared with Li-ion; the operation of the cells is discussed, as are the significant hurdles that will have to be overcome if such batteries are to succeed. Fundamental scientific advances in understanding the reactions occurring in the cells as well as new materials are key to overcoming these obstacles. The potential benefits of Li-air and Li-S justify the continued research effort that will be needed.
7,895 citations
TL;DR: Li-ion battery technology has become very important in recent years as these batteries show great promise as power sources that can lead us to the electric vehicle (EV) revolution as mentioned in this paper.
Abstract: Li-ion battery technology has become very important in recent years as these batteries show great promise as power sources that can lead us to the electric vehicle (EV) revolution. The development of new materials for Li-ion batteries is the focus of research in prominent groups in the field of materials science throughout the world. Li-ion batteries can be considered to be the most impressive success story of modern electrochemistry in the last two decades. They power most of today's portable devices, and seem to overcome the psychological barriers against the use of such high energy density devices on a larger scale for more demanding applications, such as EV. Since this field is advancing rapidly and attracting an increasing number of researchers, it is important to provide current and timely updates of this constantly changing technology. In this review, we describe the key aspects of Li-ion batteries: the basic science behind their operation, the most relevant components, anodes, cathodes, electrolyte solutions, as well as important future directions for R&D of advanced Li-ion batteries for demanding use, such as EV and load-leveling applications.
5,531 citations
TL;DR: The Review will consider some of the current scientific issues underpinning lithium batteries and electric double-layer capacitors.
Abstract: Energy-storage technologies, including electrical double-layer capacitors and rechargeable batteries, have attracted significant attention for applications in portable electronic devices, electric vehicles, bulk electricity storage at power stations, and “load leveling” of renewable sources, such as solar energy and wind power. Transforming lithium batteries and electric double-layer capacitors requires a step change in the science underpinning these devices, including the discovery of new materials, new electrochemistry, and an increased understanding of the processes on which the devices depend. The Review will consider some of the current scientific issues underpinning lithium batteries and electric double-layer capacitors.
2,412 citations
IBM1
TL;DR: In this article, the authors summarized the promise and challenges facing development of practical Li−air batteries and the current understanding of its chemistry, and showed that the fundamental battery chemistry during discharge is the electrochemical oxidation of lithium metal at the anode and reduction of oxygen from air at the cathode.
Abstract: The lithium−air system captured worldwide attention in 2009 as a possible battery for electric vehicle propulsion applications. If successfully developed, this battery could provide an energy source for electric vehicles rivaling that of gasoline in terms of usable energy density. However, there are numerous scientific and technical challenges that must be overcome if this alluring promise is to turn into reality. The fundamental battery chemistry during discharge is thought to be the electrochemical oxidation of lithium metal at the anode and reduction of oxygen from air at the cathode. With aprotic electrolytes, as used in Li-ion batteries, there is some evidence that the process can be reversed by applying an external potential, i.e., that such a battery can be electrically recharged. This paper summarizes the authors’ view of the promise and challenges facing development of practical Li−air batteries and the current understanding of its chemistry. However, it must be appreciated that this perspective ...
2,308 citations