Following Whittingham’s first reversible intercalation electrode (1976) and Goodenough’s identification of oxides as more viable materials (1980), it took a decade for the modern lithium-ion batteries (LIBs) to be invented (Sony 1990 and Sanyo 1994). It would take another decade for LIB to revolutionize our life. Due to the thermodynamic limits imposed by the intercalation chemistry nature, LIBs cannot meet the expectations of most emerging applications. The call for a better battery chemistry is never so urgent. In this talk I will review the key historical events that led to the invention of LIB, and discuss the possibilities of designing the next generation batteries with the aid of the contemporary AI revolution.

Over the past decade or so there has been immense interest in flow batteries for large scale energy storage, especially for 8+ hour storage applications.  Conventional approaches take advantage of metal and non-metal redox species in aqueous and non-aqueous organic solvents.  In our approach we are exploring structured electrolytes that have a high degree of tailoring ability to optimize energy density, enhance power density, and create safe and environmentally benign energy storage devices.  In this presentation I will discuss two approaches we are taking in the DOE EFEC Breakthrough Electrolytes for Energy Storage.  In the first approach we are exploring the nanostructure concentrate hydrogen bonded electrolytes (CoHBES). Fundamental studies have been carried out on understanding structure of model systems such as deep eutectic solvents (DESs) and how these structures relate to dynamics of transport and solvation properties of the electrolyte.  The second approach are meso-scale structured electrolytes based on microemulsions.  Again, the key findings of a model system will be described.   The presentation will also talk about how we are moving from model system studies towards discovery of new compositions and understanding of these systems.  
Finally, the presentation will include a discussion of a slurry electrolyte (micro-scale structure). In this case we describe the path from understanding mechanism of current distribution to particles through developing and commercializing an energy storage device based on an all-iron chemistry.

We demonstrate that crucial electrolyte properties such as viscosity and ionic conductivity can be accurately predicted from first principles using a charge-aware machine learning force field. By training on small clusters of a few molecules and scaling up to accurate simulations of liquid solutions, we provide a dramatic demonstration of the nearsightedness of electronic matter.

Transmission electron microscopy (TEM) has been instrumental in elucidating nano- and atomic-scale characteristics of the morphology, microstructure, and chemical properties of electrode materials used in battery systems. Furthermore, advancements in its in situ capabilities present a valuable opportunity to observe dynamic changes occurring in electrodes under external stimuli, facilitating a deeper understanding of material behavior under varying conditions. In my presentation, I will discuss insights gained from TEM observations related to the thermal degradation of charged cathode materials, phase transformations of electrodes during lithiation, and the structural characteristics of the solid electrolyte interphase. Additionally, I will highlight emerging electron microscopy capabilities at the Center for Functional Nanomaterials, aiming to foster collaborative efforts toward scientific discoveries.

Zinc ion batteries are a niche alternative for battery applications. Their implementation is however afflicted by several factors, one of which is the need for more efficient electrolytes. Deep eutectic solvent (DES) electrolytes based on zinc salts offer many attributes including improved stability and reduced dendrite formation. In this work we will present a molecular level understanding of the ion dynamics in electrolyte mixtures based on the ZnCl2 and ZnBr2 salts combined with various hydrogen bond donor solvents. Focus is on the ion dynamics as interrogated by multi-nuclear NMR relaxometry and diffusometry, combined with bulk ionic conductivity, viscosity and density measurements.

The development of technologies capable of capturing and storing carbon dioxide emissions, either from the air or directly at emission sources, is driven by the urgent need to combat climate change. Electrochemically driven carbon capture and release at ambient temperature and pressure, through the formation of complexes with organic redox-active molecules [1,2] or via pH swings induced by proton-coupled electron transfer during redox reactions [3,4], has demonstrated significant potential in terms of energy efficiency, scalability, and safety, surpassing conventional amine scrubbing technologies [5].
One of the promising electrochemical carbon capture systems relies on quinone chemistry. Quinones offer two distinct mechanisms for CO₂ capture: (a) Upon electrochemical reduction, the carbonyl groups serve as sites for the nucleophilic addition of carbon dioxide, leading to the formation of a quinone-CO₂ adduct (CO₂ reversibly bound by quinones). (b) Depending on the quinone’s pKa and the local pH, electrochemical reduction may also be proton-coupled, generating hydroxide, which captures CO₂ in the form of carbonate or bicarbonate. Thus, in an aqueous solvent, both pH-swing and nucleophilic-swing mechanisms may contribute to CO₂ capture across a range of operational conditions.
Traditional methods for measuring the total amount of CO₂ captured or released only report the combined contribution of these two mechanisms; the relative contributions remain unknown. Understanding the dominance of one mechanism over the other affects critical performance metrics of the final engineered electrochemical cell, including capture capacity, energy efficiency, stability, kinetic and reaction rates, and material selection, necessitating specific molecular engineering considerations in the material discovery cycle. In this work, we introduce in situ electrochemical characterization and in situ fluorescence microscopy to independently measure these two pathways for CO₂ capture. These non-invasive in situ techniques enable real-time distinction, with sub-second resolution, between oxidized, reduced, and adduct species based on their electrochemical and fluorescence profiles. The findings of this study provide deeper insights into the dual contributions of the quinone-CO₂ adduct and pH-swing mechanisms in carbon capture and release, while also presenting advanced non-invasive methods for investigating similar systems.
¹X. Li, X. Zhao, Y. Liu, T.A. Hatton, and Y. Liu, "Redox-tunable lewis bases for electrochemical carbon dioxide capture", Nature Energy7, 1065 (2022).
²Y. Liu, H.Z. Ye, K.M. Diederichsen, T. Van Voorhis, and T.A. Hatton, "Electrochemically mediated carbon dioxide separation with quinone chemistry in salt-concentrated aqueous media", Nat Commun11, 2278 (2020).
³S. Jin, M. Wu, Y. Jing, R.G. Gordon, and M.J. Aziz, "Low energy carbon capture via electrochemically induced pH swing with electrochemical rebalancing", Nat Commun13, 2140 (2022).
⁴S. Jin, M. Wu, R.G. Gordon, M.J. Aziz, and D.G. Kwabi, "pH swing cycle for CO2 capture electrochemically driven through proton-coupled electron transfer", Energy & Environmental Science13, 3706 (2020).
⁵G.T. Rochelle, "Amine scrubbing for CO2 capture", Science325, 1652.

Solid oxide cells (SOCs) with bidirectional operation have advantages over other types of energy storage systems since they may be deployed in time-shifting, long-duration, and seasonal storage applications while having lower life cycle environmental impacts and can be manufactured from readily abundant elements and materials. Several developers are upscaling this technology to MW scales. This presentation examines the technical and economic viability of grid-scale energy storage systems based on high-temperature, stand-alone reversible solid oxide electrochemical systems at the 1 MW (8 MWh) scale using H2-H2O chemistry. A multi-scale modeling approach is employed that moves from one-dimensional cell-level models for stack performance estimation to full-scale systems with balance-of-plant models and equipment cost equations. Because of thermal management challenges associated with maintaining ReSOC stack operating conditions in either the highly endothermic or exothermic operating modes, approaches for integration of various thermal energy storage (TES) technologies are investigated towards improving the system RTE while trying to limit increases in LCOS. Both low- and high-temperature sensible and latent TES approaches are examined. The results show that a ReSOC combined with a steam accumulator which stores low-grade thermal energy (<150°C) during exothermic fuel cell operation achieves the highest system RTE (57%), representing a 6.6% point improvement over scenarios without TES. Despite the addition of new system components, the LCOS remains largely unchanged when compared to the base case. Technology attribute comparisons with conventional EES technologies are made. Lastly, the impact of mode-switching on the thermal dynamics of ReSOCs is evaluated under various inlet flow configurations.

Today, as the Energy Transition accelerates the grid towards renewable energy sources, the significance of energy storage becomes increasingly evident. Energy Storage paves the way to a net zero energy system.
Energy storage is crucial for balancing supply and demand, mitigating the intermittency of renewable energy sources, and ensuring the stability and optimization of the grid. And while investments in energy storage are projected to grow significantly over the next decade to meet clean energy objectives, these efforts are primarily driven by the need to integrate renewable resources onto the grid to ensure resource adequacy. Proactive distribution investments will also be necessary to support grid flexibility necessary to accommodate the increasing complexity of customer demand and variability of energy supply and demand. 
As more sectors of the economy and daily life become reliant on the grid, and the grid shifts to a more dynamic and mature operational state, it is critical to enhance its reliability to support society for generations to come. Robust Utility integrated storage aimed at effective grid management and optimization combined with market storage that will provide market services and balance wholesale system needs will be essential to help underpin the grid and energy system of the future.

While global energy transition is underway in various forms of decarbonization, there is little solution available for heavy industry & heavy-duty transportation. Amogy offers ammonia-based, emission-free, high-energy-density power solutions to decarbonize transportation for a sustainable future, accelerating the global journey towards Net Zero 2050. To date, Amogy’s scalable ammonia-powered, zero-emissions energy system has been demonstrated with success in a drone, heavy duty tractor, class 8 semi-truck. Amogy is currently retrofitting a 1 MW tugboat to demonstrate the world’s first ammonia-powered vessel. In this talk, Amogy's vision of decarbonization as well as technology focusing on catalyst, reactor, and system layout will be discussed.

The transition from fossil-fueled vehicles to electric transportation requires advancements in battery technology to meet the demands of rapid charging, enhanced energy density, and longevity. To address these challenges, it is critical to understand the intricate chemical processes that occur within batteries. This presentation delves into the potential of Magnetic Resonance techniques, specifically Nuclear Magnetic Resonance (NMR) and Electron Paramagnetic Resonance (EPR), to probe these mechanisms at the molecular level, providing unmatched insights into the chemical processes of battery systems.
NMR and EPR offer unique advantages in elucidating the structure, dynamics, and interactions of battery components under operational conditions. In this talk, we will discuss how these techniques can be applied to investigate electrolytes, electrodes and interfaces. We will explore how Magnetic Resonance can shed light on key issues like capacity fade, dendrite formation, and thermal runaway, as well as exploring new materials for next-generation batteries.
By providing a deeper chemical understanding, Magnetic Resonance can guide the development of safer, more efficient, and longer-lasting batteries. This presentation will provide a comprehensive overview of current research applications and future directions, highlighting the potential of NMR and EPR in both academic and industrial battery R&D settings.

With the severity in cases of fire accidents involving electric vehicles utilizing high energy density battery materials, the present research deals in enhancing the proposed thermal explosion theory for lithium-ion batteries to acknowledge the thermal runaway (TR) characteristics under non-linear passive and active air-cooling conditions. In our earlier theory, a constant value of heat transfer coefficient (h) was utilized for Newton’s law of cooling (Heat Loss Term) and evaluation of equilibrium (TE) and maximum (TM) temperature was achieved stating that TR occurs when TE>TM. The present model identifies a cut-off Reynolds number (Re) under forced convection beyond which TR is inevitable. Samples of high-capacity Li-ion battery with 91% Nickel-content were prepared, utilizing Argon glove-box to avoid contamination. Heat generated during thermal decomposition of battery cell using differential scanning calorimetry (DSC) is compared with the heat loss conditions (Re=4~388) to highlight the necessary cooling condition to avoid TR and ensure battery safety. For practical operational conditions, the state of charge (SOC) and heating rate are varied. The results suggest that Re<4~40 have lower h than realistic non-linear natural-convection by around 30% at 100% SOC. For Re>234, TE exceeds TM leading to TR although the cooling effect is increased for 100% SOC at 10 oC/min heating rate. A cut-off Re shows a quadratic correlation with heating rate for a particular SOC. The present work suggests that beyond cut-off Reynolds number, the cooling effect can also become a factor resulting in battery fire and explosion incidents.

Achieving the net-zero emissions goal requires a significant increase in electricity production from renewable technologies and widespread electrification of the transportation sector. These pressing challenges highlight a substantial gap between growing manufacturing demand and current production capacity, necessitating innovative solutions to secure resource supplies and enhance manufacturing capabilities. Ions, as the simplest unit for separation and synthesis, are critical to control to enable transformative technologies. In this talk, I will introduce our group’s research in understanding and manipulating ions at electrified interfaces for separation and manufacturing. Specifically, I will introduce electrochemical intercalation as a platform method for lithium (Li) extraction. By studying the complex behavior of two model hosts—olivine-type and layered oxides—during the co-intercalation of competing ions, we have developed several strategies to enhance Li selectivity. Our understanding of ion behavior also provides important insights for enabling predictive ion-exchange-based synthesis.

Moving toward substantive decarbonization will require energy storage. Not just batteries, but this age-old technology will play a key role, especially if the battery components are more sustainable. That means aqueous electrolytes and active materials composed of low supply–risk elements (i.e., not cobalt). Our team at the Naval Research Laboratory designs pore–solid nanoarchitectures that capture all of the requisite transport functions for high performance in electrochemical energy storage, molecular mass transport, ionic/electronic/thermal conductivity, and electron-transfer kinetics. The lessons we learned from 20 years of fundamental research into the operational and design characteristics of energy-relevant nanoarchitectures led us to the sponge form factor. Zinc sponges are monolithic, scalable objects that lower and distribute the current density within the porous electrode interior during charge–discharge cycling in alkaline batteries such that cell-shorting dendrite-formation cannot occur. With this breakthrough, we are protyping the family of zinc-based rechargeable alkaline batteries: nickel–3D zinc (electrified multi-wheeled vehicles), silver–3D zinc (time for electric trains!), MnO₂–3D zinc (grid storage), and even rechargeable 3D zinc–air.  

Water electrolyzers are today of worldwide strategic importance for the deployment of green hydrogen as an energy carrier, and the ultimate integration of stochastic renewable energies into the electrical grid at scale. Targets for the total cost of ownership of hydrogen have been constantly revised, but values around $2 per kilogram of H2 are generally accepted to reach parity with other energy conversion and storage strategies. However, further advancement of electrolyzers while maintaining durability and robustness of its cell/stack components is still needed. This can only be accomplished through focused research and development efforts that address efficiency, degradation, and cost aspects of the technology.

There are numerous new battery chemistries under development for both transportation and grid applications, including solid-state Li metal batteries, Na-based batteries, and numerous others. A challenge for the evaluation and development of these new chemistries is that battery safety is typically only assessed once a multi-Ah cell in a commercial format is developed, which often takes many years and investments to achieve. This talk will discuss approaches to assess the safety of new battery chemistries at an early, materials-scale stage, helping to spur understanding and innovations in the safety of new battery chemistries even before a commercial prototype is available.

When is a short bad, and when is it really bad? Let’s discuss.

We report a zero-waste, continuous flow electrosynthesis process to produce a high-performance, long lifetime organic flow battery negolyte at the ton scale. The yield and purity are even higher than the equivalent chemical process and no further purification or downstream processing is required, which greatly simplifies scaleup, permitting, and implementation. Moreover, the as-produced material can be immediately cycled as a drop-in replacement for vanadium in conventional flow battery hardware with minimal modification. Together, the low cost and rapid scalability of the organic electrolyte represents a practical way for the flow battery industry to break below the cost floor imposed by vanadium and stay competitive with lithium-ion batteries.

Sodium-ion batteries are a rapidly maturing technology, addressing a critical need for safe, sustainable energy storage. Here, we discuss current industry trends and explore the possibility for sodium-ion technologies to change how battery systems are manufactured and deployed.

Zinc-air batteries (ZABs) have recently attracted considerable attention due to their high energy density and safety, low noise, and environmental friendliness. However, the capacity of mechanically rechargeable ZABs was limited by the zinc anode, which can be cumbersome to replace after each full discharge, while electrically rechargeable ZABs suffer from issues such as low depth of discharge, zinc dendrite and dead zinc formation, as well as sluggish oxygen evolution reaction, etc. To address these issues, we report a hybrid redox-mediated zinc-air fuel cell (HRM-ZAFC) that utilizes a phenazine derivative, 7,8-dihydroxyphenazine-2-sulfonic acid (DHPS), as the redox mediator in the anolyte. With the redox-targeting reaction between DHPS and zinc loaded in a fuel tank, the reaction of zinc is shifted from the electrode surface to a separate fuel tank, enabling decoupled fuel feeding and electricity generation. As a result, the system provides great operation flexibility and scalability for large-scale power generation applications. The DHPS-mediated ZAFC showed a superior peak power density of 0.51 W/cm² and a continuous discharge capacity of 48.82 Ah with ZnO as the discharge product in the tank, highlighting its potential as a useful power generation system. Detailed mechanistic studies of the redox-targeting reaction between DHPS and Zn in alkaline conditions reveal that soluble [Zn(OH)₄]^2- is first generated, followed by the formation of Zn(OH)₂ and ZnO precipitates when [Zn(OH)₄]^2- becomes saturated in the anolyte. Based on the comprehensive COMSOL simulations, future studies will be focused on the optimization of anode design for enhanced anolyte flow and consequently anodic current.

U.S. energy needs have changed dramatically over the last few decades, and it is questionable whether our grid can manage these new demands. City populations are growing, creating a greater need and forcing the expansion of power grids. The data centers behind AI-powered technologies have significant power demands. And as more drivers switch to electric vehicles and hybrids, more electricity is needed for charging stations. Renewable energy sources are expected to double by 2050. The inherent variability of renewables brings challenges, such as imbalances in supply and demand, overloaded transmission systems and capacity challenges created during weather events. Long-duration energy storage systems (LDES) will be necessary to improve the efficiency, reliability and resilience of the grid by reducing power surges and balancing the load over time. The grid design will need to be transformed for distributed energy resources. With management systems, optimized energy management across a network can be achieved by leveraging the LDES for many purposes from peak shaving to frequency matching to safety controls. Vanadium Redox Flow Batteries (VRFB) are ideally suited for grid-connected applications. VRFB systems can function for more than two decades without the electrolyte losing capacity, complementing the lifespan of wind and solar installations. The electrolyte is also infinitely recyclable, making VRFB a sustainable energy storage technology. With so many properties that make VRFB systems a safe, reliable, and sustainable option, they’re a good fit for storing and deploying the vast levels of clean energy the U.S. will need to provide greater grid stability.