Second-Annual Scialog: Advanced Energy Storage
The second-annual Scialog: Advanced Energy Storage conference held in Tucson, AZ, Nov. 8-11 drew 58 Scialog Fellows and eight senior advisors, along with several observers to the innovative process of open dialog and the formation of competitive teams.
“Scialog’s over-arching purpose is to help solve real-world problems of global significance by catalyzing innovative, basic research leading to fundamental discoveries,” RCSA President Daniel Linzer told the participants. “Our focus is on scientists in the early years of their independent careers. Through the unique Scialog process, we seek to lay the foundation for an ongoing, highly creative, cross-disciplinary community of energy scientists that will prove adept at identifying exciting areas for research advances.”
Jointly sponsored by Research Corporation and the Alfred P. Sloan Foundation, the conference featured Sarbajit Banerjee, Texas A&M, delivering the conference keynote speech on the subject of “Defining Conduction Pathways in Cathode Materials: Resolving Logjams through Atomistic Design and Mesoscale Structuring.“
Banerjee said the deficiencies of electrochemical energy storage are a major constraint in many areas of technological design. Using a canonical intercalation host, V2O5, as a model system, he discussed the structural and electronic origins of diffusion barriers in cathode materials, adding that the stabilization of metastable phases provide frustrated coordination environments and enable the relatively facile diffusion of polarons.
“This approach has led to the discovery of several promising intercalation hosts for Mg- and Ca-ion batteries,” he said, focusing further discussion on a tunnel-structured ζ-V2O5 polymorph that “provides an unprecedented combination of high voltage, excellent cyclability, and good capacity.” He then discussed further elaboration of this concept to other polymorphs of V2O5.
“A promising advantage of switching to Mg-based batteries derives from the many reports which claim that Mg is inherently non-dendrite forming,” Banerjee noted before examining the issue of whether Mg is truly impervious to dendritic growth.
Facilitators for scientific discussions central to the Scialog conference included Banerjee as well as Mookie Baik, Korea Advanced Institute of Science and Technology; George Crabtree, Argonne National Laboratory; Prashant Kamat, University of Notre Dame; Karl Mueller, Pacific Northwest National Laboratory; Amy Prieto, Colorado State University; Stan Whittingham, Binghampton University; and Yiying Wu, The Ohio State University.
Discussion sessions during the four-day conference covered the following topics:
Anion Redox: Strategies for designing hosts and electrolytes for anions, underlying reaction mechanisms, developing experimental methods for identifying which species is contributing toward the observed redox activity, prospects and pitfalls.
Conversion Chemistries: Prospects and Bottlenecks: Design principles for conversion reactions, bottlenecks to realization of full potential of Li/S and Na/S chemistries, delineation of reaction mechanisms, operando measurements, avoiding dead-ends, mesostructure design.
Coupling Theory and Experiment: Identifying disconnects, bridging scales, modeling of rare events, and away-from-equilibrium phenomena, integrating different theoretical tools to model events over a range of time and length scales.
Defects and Disorder: Understanding role of defects in mediating ion transport, the dynamical evolution of defects, incorporation of defects by design, elucidation of electrochemical processes at defect sites, and defects as sinks to mitigate degradation phenomena.
Electrocatalysis in Energy Storage: Interfacing with photochemical processes, design principles, biomimetic approaches, single-atom catalysis, using catalytic processes to resolve bottlenecks in conversion chemistries.
Electrolyte Interfaces: Understanding electrochemical reactions at interfaces, reaction design at interfaces, characterization of interfacial structure and its dynamical evolution, surface modification as a means of altering interfacial reaction pathways, challenges with developing meaningful theoretical descriptions of interfaces, predicting cycle life.
Energy Dense Aqueous Chemistries: Delineating design principle and pushing limits of aqueous chemistries, pseudocapacitative mechanisms in aqueous media, design, synthesis and fabrication of new materials and electrode architectures to facilitate aqueous energy storage systems.
Fast Charging in Redox Systems: Fundamental bottlenecks to rapid kinetics of ion insertion/extraction, materials solutions, mesoscale design, electrode and full cell architectures, engineering controlled porosity.
High Energy Density Cathodes: Design of high energy density cathode materials, chemical storage reactions beyond intercalation, challenges and prospects for accessing multi-redox chemistry, quantum batteries, stability considerations.
Machine Learning for Energy Storage: Curation and generation of data sets for machine learning, robotic experimentation, high-throughput approaches, achieving the meaningful fusion of experimental data from disparate sources with computed data.
Mesoporous Frameworks for Energy Storage: Design of metal-organic frameworks as intercalation hosts and solid-state electrolytes, electrodes with controlled porosity
Metal Anodes: Li Metal and Beyond: Li Metal and Beyond: The fundamental behavior of metal anodes, mechanistic understanding of electrodeposition reactions, challenges with electrolyte compatibility and low current densities, design of reversible plating reactions.
Multivalent Batteries: Cathodes: Understanding design principles, overcoming limitations of computational materials design, operando characterization of multivalent intercalation hosts.
Operando Characterization of Electrochemical Processes: Pushing limits of spatial and temporal resolution, examining buried interfaces, evolution of surfaces under reaction conditions, translating learnings from model systems to real cells, understanding and predicting degradation mechanisms, and connecting experiments to simulations.
Organic Redox Materials: Elucidation of structure—function correlations in organic redox materials, commonalities and distinctions in needs for flow batteries and solid-state organic systems, understanding electrode reactions, increasing charge capacity of redox-active, organic molecules while maintaining solubility and atom economy.
Solid-State Electrolytes: Theoretical limits to the performance of solid-state electrolytes, understanding design principles, operando studies of diffusion mechanisms, challenges with studying buried interfaces, use of novel electrolytes to enhance cell safety, and strategies to mitigate dendrite formation.
Sustainable Design: Development of sustainable and earth-abundant materials as well as sustainable manufacturing processes, recycling of battery materials, understanding the environmental impact of battery materials and manufacturing processes.
Synthesis Pathways and Metastable Compounds: Elucidation of synthetic pathways through in situ methods, mining of metastable phase space, opportunities and pitfalls for electrochemical energy storage, the search for synthetic approaches to prepare targets identified by computational materials design.
Formal and informal discussions culminated Sunday morning in the Scialog Fellows’ competitive presentations of 24 research proposals for possible funding. RCSA Senior Program Director Richard Wiener said the Scialog Advisory Committee will be making funding recommendations in the next few weeks for projects which will start in early 2019.
“Research Corporation chose to focus on advanced energy storage because we believe this critical area of science requires major breakthroughs in fundamental understanding of electrochemical and physical processes that will lead to a new era of technological advance,” Wiener noted. “Just as firmly, we believe these breakthroughs can be accelerated by chemists, engineers, material scientists and physicists working collaboratively on novel, high-risk projects, particularly with theorists and experimentalists combining efforts.”
