Rechargeable metal-based batteries play a pivotal part in electrochemical energy storage, but the formation of metal dendrite on the surface of anode causes serious safety concerns and limited cycle life. Recently, electrodeposition, an ancient fabrication technique, was used to annihilate the dendrite via an epitaxial nucleation in batteries.1 This innovation will accelerate the metal-based batteries from academia to industry.

Ammonia synthesis underpins modern life but carries a high energy and carbon cost. Recent electrochemical alternatives focus on ambient, aqueous systems with little current prospect for application. Here, Kyriakou et al.1 demonstrate a high-temperature and ambient pressure solid-state approach coupling methane steam reforming with ammonia synthesis to decrease energy usage.

The high-grade heat required for heavy industry—such as for the production of cement, steel, petrochemicals, and glass—accounts for nearly 10% of global CO2 emissions. The pathways to decarbonizing this sector are unclear. Friedmann and colleagues have recently examined the state of low-carbon heating approaches for heavy industry. Existing options are costly, inadequate, or both. Increased efforts to decarbonize this sector through policy instruments and technology innovation are urgently needed.

A microbial battery couples waste degradation to a specific enzymatic production process. This is enabled by the uncoupling of the waste oxidation process from the enzymatic bioproduction via redox cathodes. The approach can be attractive for small-scale, local production of chemicals from water and/or CO2.

Despite rising greenhouse gas emissions, the rapid diffusion of solar-PV, wind turbines, and light-emitting diodes (LEDs) is beginning to change the climate change discourse from one that focuses on collective action problems, free-riding concerns, and zero-sum games to one that focuses on economic opportunities, innovation races, and win-win solutions.1 In a rich and interesting article, titled “Recalibrating climate prospects,” Lovins et al.2 make three major contributions to this changing discourse.

The exploration of highly active, durable, and cost-effective electrocatalysts for the oxygen reduction reaction (ORR) is indispensable for several important energy conversion technologies. Significant achievements have been made with numerous efforts devoted by the academic and industrial researchers. In this review, from a more practical point of view, the tests and experiments at the membrane electrode assembly (MEA) level are accentuated due to the fact that the rotating disk electrode (RDE) level performance cannot be transformed directly into the MEA level. Four major categories of the current ORR electrocatalysts are discussed, namely, platinum group metal (PGM or noble) catalysts, non-PGM catalysts, carbon-based catalysts, and single-atom-based catalysts. The advantages and shortcomings, along with the performance achieved by the catalysts, are briefly reviewed, and the improvement in the rational design approaches is emphasized at the full-cell level. Finally, the present challenges and prospects are discussed for developing advanced ORR electrocatalysts.

Chibueze is currently an assistant professor at the Pritzker School of Molecular Engineering at the University of Chicago where his research group focuses on tackling the challenges (some of which are detailed here) related to electrolytes for energy storage and electrocatalysis. He obtained his PhD from the Massachusetts Institute of Technology (MIT), did his postdoctoral work at Stanford University, and was a visiting fellow at the University of Cambridge (UK). His PhD and postdoctoral work focused on understanding electrolyte instability and designing new electrolytes for lithium-air and lithium-metal batteries.

Hydrogen peroxide is the focus of growing attention for distributed manufacturing, reflecting its decentralized applications and shipping hazards. Two recent reports, one in Science by Wang and colleaugues and one in this issue of Joule by Surendranath, Hatton, and colleaugues, introduce innovative electrochemical methods to produce electrolyte-free aqueous solutions of hydrogen peroxide.

Benchmark solar to hydrogen conversion efficiency of 18.7% was achieved via photovoltaic cell–electrolyzer system without using well-known expensive III-V-based light absorber. Comparison with previous studies indicates that this efficiency bench is impressive for using less junction (2jn instead of 3∼4jn for III/V), relatively cheap perovskite and silicone solar cell, and high solar electricity to chemical efficiency (74.2%).

Decarbonizing the electricity sector is an urgent global energy challenge. Recently in Energy Research and Social Science, Barido et al. used data mining approaches on a large set of factors that influence decarbonization progress across 130 countries. Their findings led them to propose a new framework to determine an effective set of region-specific support mechanisms to sustain a long-term clean energy transition.

The United States electricity grid is undergoing rapid changes in response to the sustained low price of natural gas, the falling cost of electricity from variable renewable resources (which are increasingly being paired with Li-ion storage with durations up to ∼4 h at rated power), and state and local decarbonization policies. Although the majority of recent electricity storage system installations have a duration at rated power of up to ∼4 h, several trends and potential applications are identified that require electricity storage with longer durations of 10 to ∼100 h. Such a duration range lies between daily needs that can be satisfied with technologies with the cost structure of lithium-ion batteries and seasonal storage utilizing chemical storage in underground reservoirs. The economics of long-duration storage applications are considered, including contributions for both energy time shift and capacity payments and are shown to differ from the cost structure of applications well served by lithium-ion batteries. In particular, the capital cost for the energy subsystem must be substantially reduced to ∼3 $/kWh (for a duration of ∼100 h), ∼7 $/kWh (for a duration of ∼50 h), or ∼40 $/kWh (for a duration of ∼10 h) on a fully installed basis. Recent developments in major technology classes that may approach the targets of the long-duration electricity storage (LDES) cost framework, including electrochemical, thermal, and mechanical, are briefly reviewed. This perspective, which illustrates the importance of low-cost and high-energy-density storage media, motivates new concepts and approaches for how LDES systems could be economical and provide value to the electricity grid.

David Wood is a Senior Staff Scientist and University of Tennessee Bredesen Center Adjunct Faculty Member at Oak Ridge National Laboratory (ORNL), researching novel electrode architectures, mass transport phenomena, solid-liquid surface chemistry, advanced processing methods, manufacturing science, and materials characterization for low-temperature fuel cells, PEM electrolyzers, and lithium-ion batteries, and has been employed there since 2009. He is also the former ORNL Fuel Cell Technologies Program Manager (2011–2018), the former Roll-to-Roll Manufacturing Team and Group Leader (2015–2017), and a well-known energy conversion and storage researcher with an industrial and academic career that began in 1995. From 1997 to 2002, he was employed by General Motors Corporation and SGL Carbon Group, excelling at applied R&D related to automotive and stationary PEFC technology. Later work (2003–2009) at Los Alamos National Laboratory (LANL) and Cabot Corporation focused on elucidation of key chemical degradation mechanisms, development of accelerated testing methods, and component development. Dr. Wood received his BS in Chemical Engineering from North Carolina State University in 1994, his MS in Chemical Engineering from the University of Kansas in 1998, and his PhD in Electrochemical Engineering from the University of New Mexico in 2007. He was part of two LANL research teams that won the DOE Hydrogen Program R&D Award for outstanding achievement in 2005 and 2009. He was also part of the Cabot Corporation Direct Methanol Fuel Cell team, which won the Samuel W. Bodman Award for Excellence in 2008. Dr. Wood was also the 2011 winner of the ORNL Early Career Award for Engineering Accomplishment and led a team that won both a 2013 R&D 100 award and 2014 Federal Laboratory Consortium (FLC) award with Porous Power Technologies. He has received 19 patents and patent applications, authored 93 refereed journal articles and transactions papers, and authored 2 book chapters. Jianlin Li is a R&D Staff and University of Tennessee Bredesen Center Adjunct Faculty Member at Oak Ridge National Laboratory (ORNL). His research interest lies in materials synthesis, processing and characterization, electrode engineering, and manufacturing for energy storage and conversion. Dr. Li received his BS in Materials Chemistry and his MS in Materials Science from University of Science and Technology of China in 2001 and 2004, respectively, and his PhD in Materials Science and Engineering from the University of Florida in 2009. He is a recipient of several prestigious awards including two R&D 100 awards and one Federal Laboratory Consortium (FLC) award. He has received 14 patents and patent applications and authored 96 refereed journal articles and 3 book chapters. Seong Jin An is a Principal Engineer at Samsung Electronics leading rechargeable battery platforms for smartphone applications and has been employed there since late 2017. He had researched solid electrolyte interphase (SEI) in the lithium-ion battery as a guest at Oak Ridge National Laboratory (ORNL) (2014–2017). He worked at Samsung SDI in South Korea as a senior engineer developing PEM fuel cell stacks (2003–2011) and GS Fuel Cell in South Korea developing fuel processors for PEM fuel cell systems (2001–2003). He received his BS in Chemical Engineering from Seoul National University of Science and Technology in 1999, his MS in Chemical Engineering from Yonsei University, Seoul in 2001, his MS in Mechanical Engineering from Carnegie Mellon University, Pittsburgh in 2014, and his PhD in Energy Science & Engineering from University of Tennessee, Knoxville in 2017. He studied PEM fuel cells and lithium-ion batteries with fellowships during his MS and PhD programs. He has received over 200 patents and authored 21 refereed journal articles and transactions papers.

Ding Ma is a professor of Peking University. He is an advisory member for various journals, has been Associate Editor for the catalysis journal of RSC, Catalysis Science & Technology, since 2014, and was elected as a Fellow of the Royal Society of Chemistry in 2016. His research interests are heterogeneous catalysis, especially those related with energy issues, including C1 chemistry (methane, CO2, and syngas conversion), new reaction routes for sustainable chemistry, and the development of an in situ spectroscopic method that can be operated at working reaction conditions to study reaction mechanisms. Bingjun Xu is an Associate Professor in the Department of Chemical and Biomolecular Engineering at University of Delaware. He received his PhD in Physical Chemistry, advised by Prof. Friend, from Harvard University in 2011 and worked with Prof. Davis at Caltech as a postdoctoral researcher. The overarching goal of Xu research group is to develop innovative strategies to produce renewable electricity, fuels, and chemicals by the rational design of efficient thermo- and electro-catalytic processes. A special focus is placed on the mechanistic understanding of surface-mediated reactions by employing and developing state-of-the-art spectroscopic and kinetic techniques. Meng Wang is a Research Scientist in the College of Chemistry and Molecular Engineering at Peking University. He received his PhD in Chemistry from Technical University of Munich, advised by Prof. Lercher, in 2018 and worked in Pacific Northwest National Laboratory as a Research Associate from 2015 to 2019. Wang’s principal research task focuses on deciphering the kinetic and mechanistic pathways for catalytic reactions by combining reaction kinetics, isotopic experiments, and various in situ characterization methods. Mengtao Zhang is a PhD student in the College of Chemistry and Molecular Engineering at Peking University (Prof. Ding Ma). He received his BS (Chemistry) from Nanjing University in 2015. His research interests include water activation and hydrogen production, CO2 and other greenhouse gas conversion into desirable chemicals, design and development of new catalysts, and operando reaction mechanism and kinetics study.

Paul Joskow is the Elizabeth and James Killian Professor of Economics, Emeritus, at the Massachusetts Institute of Technology (MIT) where he joined the faculty in 1972. He has served as the Chairman of the Department of Economics and as the Director of the Center for Energy and Environmental Policy Research. From 2008 to 2017, he was the President of the Alfred P. Sloan Foundation. He is a Fellow of the American Academy of Arts and Sciences and the Econometric Society, and a Distinguished Fellow of the American Economic Association and of the Industrial Organization Society. He has published widely on topics in industrial organization, energy economics, electricity markets, and government regulation.

The cost of renewable energy generation has rapidly dropped over the last decade due to numerous factors, including widespread government subsidies. Now unsubsidized wind and solar photovoltaics are starting to be cost competitive in wholesale electricity markets. But will this continue? Recently in Nature Sustainability, Schmidt et al. reported that rising interest rates could stagnate or even reverse falling pricing trends of renewables.

Accurate prediction of battery failure, both online and offline, facilitates design of safer battery systems through informed-engineering and on-line adaption to unfavorable scenarios. With the wide range of batteries available and frequently evolving pack designs, accurate prediction of cell behavior under different conditions is very challenging and extremely time consuming. In this issue of Joule, Li et al.1 used data from a previously reported finite-element model to train machine learning algorithms to predict whether a cell will undergo an internal short circuit when exposed to a selection of mechanical abuse conditions. The presented approach aims to alleviate, and yet is still limited by, a common challenge facing data-driven prediction methods: access to robust, plentiful, high-quality, and relevant experimental data.

An electrolyte that conducts both oxygen ions and protons has the potential to enable a solid oxide fuel cell (SOFC) to operate at lower temperatures with a variety of fuels. Now a composite cathode conducting electrons, oxygen ions, and protons shows promise for high-performance SOFC at T < 600°C.

Stability of small area perovskite solar cells has been notably improved, but large area modules have not been proven stable. Recently in Joule, E. Bi and coworkers present a highly stable perovskite module that kept 90% of its initial efficiency after 1,000 h operation under illumination. The secret is an iodide diffusion blocking layer (DBL) added at the module interconnection. The DBL with 2D graphitic carbon nitride (g-C3N4) flakes can suppress iodide diffusion at the interconnection and prevent electrode corrosion.

Joonbaek Jang received his B.S. from Korea University in 2016. He then moved to the University of Pennsylvania where he obtained his M.S. working with Prof. Raymond J. Gorte. During his master’s degree, Joonbaek used atomic layer deposition to modify metal oxide catalysts for the improvement of industrial catalytic processes. In 2018, he joined the Morales-Guio Lab in the Department of Chemical and Biomolecular Engineering at UCLA. Joonbaek is currently working toward the understanding of electrode/electrolyte interfaces and mass transport effects in electrocatalytic processes for sustainable energy applications. Kangze Shen received his B.S. in Materials Chemistry from University of Science and Technology of China in 2018. His undergraduate research with Prof. Yitai Qian focused on the development of high-performance electrode materials for rechargeable Li-ion and Na-ion batteries. He then joined the Morales-Guio Lab in the Department of Chemical and Biomolecular Engineering at UCLA where he is working toward the understanding of electrocatalytic processes and electrochemical systems engineering in sustainable energy applications. Carlos G. Morales-Guio is an Assistant Professor of Chemical and Biomolecular Engineering at UCLA. The Morales-Guio Lab is interested in electrochemical catalysis, particularly with respect to energy and chemical transformations for sustainable energy applications. The lab is currently focused on understanding fundamentals of mass and charge transport coupled to electrochemical transformations that will guide the scale up of electrocatalytic reactors. Carlos received his B. Eng. degree from Osaka University in 2011 and his M.S. and Ph.D. in Chemistry and Chemical Engineering from EPFL in 2013 and 2016, respectively. Most recently, he was a postdoctoral research fellow at Stanford University before joining UCLA in 2018.

In a recent issue of the Journal of the Electrochemical Society, Dahn and coworkers set the standard not only for the performance level that batteries should strive to achieve but also for how batteries should be tested.

Lithium-ion batteries (LIBs) play a significant role in our highly electrified world and will continue to lead technology innovations. Millions of vehicles are equipped with or directly powered by LIBs, mitigating environmental pollution and reducing energy use. This rapidly increasing use of LIBs in vehicles will introduce a large quantity of spent LIBs within an 8–10-year span. Proper handling of end-of-life (EOL) vehicle LIBs is required, and multiple options should be considered. This paper demonstrates that the necessity for EOL recycling is underpinned by leveraging fluctuating material costs, uneven distribution and production, and the transport situation. From a life-cycle perspective, remanufacturing and repurposing extend the life of LIBs, and industrial demonstrations indicate that this is feasible. Recycling is the ultimate option for handling EOL LIBs, and recent advancements both in research and industry regarding pyrometallurgical, hydrometallurgical, and direct recycling are summarized. Currently, none of the current battery recycling technologies is ideal, and challenges must be overcome. This article is anticipated as a starting point for a more sophisticated study of recycling, and it suggests potential improvements in the process through mutual efforts from academia, industry, and governments.