Innovative L-band electron paramagnetic resonance investigation of solid-state pouch cell batteries

Usually, the conventional electron paramagnetic resonance (EPR) spectroscopy and imaging use a microwave cavity operating at X-band, i.e. with an excitation frequency of around 9.6 GHz, and remains the most popular mode in the magnetic characterization of lithium batteries to date. We provide here the first low-frequency EPR investigations for monitoring the metallic lithium structures in the solid-state pouch cell batteries. We show that L band, i.e. a microwave frequency of around 1.01 GHz, is an invaluable method to probe in depth the electrode components through a standard pouch cell using aluminum laminated film for packaging without opening the battery. These results offer a new approach for monitoring the nucleation of micrometric and sub-micrometric lithium particles such as dendritic lithium structures which is an important step in the development of reliable solid-state batteries

Revealing Nanoscale Solid-Solid Interfacial Phenomena for Long-Life and High-Energy All-Solid-State Batteries.

Enabling long cyclability of high-voltage oxide cathodes is a persistent challenge for all-solid-state batteries, largely because of their poor interfacial stabilities against sulfide solid electrolytes. While protective oxide coating layers such as LiNbO3 (LNO) have been proposed, its precise working mechanisms are still not fully understood. Existing literature attributes reductions in interfacial impedance growth to the coating's ability to prevent interfacial reactions. However, its true nature is more complex, with cathode interfacial reactions and electrolyte electrochemical decomposition occurring simultaneously, making it difficult to decouple each effect. Herein, we utilized various advanced characterization tools and first-principles calculations to probe the interfacial phenomenon between solid electrolyte Li6PS5Cl (LPSCl) and high-voltage cathode LiNi0.85Co0.1Al0.05O2 (NCA). We segregated the effects of spontaneous reaction between LPSCl and NCA at the interface and quantified the intrinsic electrochemical decomposition of LPSCl during cell cycling. Both experimental and computational results demonstrated improved thermodynamic stability between NCA and LPSCl after incorporation of the LNO coating. Additionally, we revealed the in situ passivation effect of LPSCl electrochemical decomposition. When combined, both these phenomena occurring at the first charge cycle result in a stabilized interface, enabling long cyclability of all-solid-state batteries

Pressure-tailored lithium deposition and dissolution in lithium metal batteries

A porous electrode resulting from unregulated Li growth is the major cause of the low Coulombic efficiency and potential safety hazards of rechargeable Li metal batteries. Strategies aiming to achieve large granular Li deposits have been extensively explored; yet, the ideal Li deposits, which consist of large Li particles that are seamlessly packed on the electrode and can be reversibly deposited and stripped, have never been achieved. Here, by controlling the uniaxial stack pressure during battery operation, a dense Li deposition (99.49% electrode density) with an ideal columnar structure has been achieved. Using multi-scale characterization and simulation, we elucidated the critical role of stack pressure on Li nucleation, growth and dissolution processes, and developed innovative strategies to maintain the ideal Li morphology during extended cycling. The precision manipulation of Li deposition and dissolution is a critical step to enable fast charging and low temperature operation for Li metal batteries

Bridging Nano and Micro-scale X-ray Tomography for Battery Research by Leveraging Artificial Intelligence

X-ray Computed Tomography (X-ray CT) is a well-known non-destructive imaging technique where contrast originates from the materials' absorption coefficients. Novel battery characterization studies on increasingly challenging samples have been enabled by the rapid development of both synchrotron and laboratory-scale imaging systems as well as innovative analysis techniques. Furthermore, the recent development of laboratory nano-scale CT (NanoCT) systems has pushed the limits of battery material imaging towards voxel sizes previously achievable only using synchrotron facilities. Such systems are now able to reach spatial resolutions down to 50 nm. Given the non-destructive nature of CT, in-situ and operando studies have emerged as powerful methods to quantify morphological parameters, such as tortuosity factor, porosity, surface area, and volume expansion during battery operation or cycling. Combined with powerful Artificial Intelligence (AI)/Machine Learning (ML) analysis techniques, extracted 3D tomograms and battery-specific morphological parameters enable the development of predictive physics-based models that can provide valuable insights for battery engineering. These models can predict the impact of the electrode microstructure on cell performances or analyze the influence of material heterogeneities on electrochemical responses. In this work, we review the increasing role of X-ray CT experimentation in the battery field, discuss the incorporation of AI/ML in analysis, and provide a perspective on how the combination of multi-scale CT imaging techniques can expand the development of predictive multiscale battery behavioral models.Comment: 33 pages, 5 figure

Evaluating Electrolyte–Anode Interface Stability in Sodium All-Solid-State Batteries

All-solid-state batteries have recently gained considerable attention due to their potential improvements in safety, energy density, and cycle-life compared to conventional liquid electrolyte batteries. Sodium all-solid-state batteries also offer the potential to eliminate costly materials containing lithium, nickel, and cobalt, making them ideal for emerging grid energy storage applications. However, significant work is required to understand the persisting limitations and long-term cyclability of Na all-solid-state-based batteries. In this work, we demonstrate the importance of careful solid electrolyte selection for use against an alloy anode in Na all-solid-state batteries. Three emerging solid electrolyte material classes were chosen for this study: the chloride Na2.25Y0.25Zr0.75Cl6, sulfide Na3PS4, and borohydride Na2(B10H10)0.5(B12H12)0.5. Focused ion beam scanning electron microscopy (FIB-SEM) imaging, X-ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy (EIS) were utilized to characterize the evolution of the anode–electrolyte interface upon electrochemical cycling. The obtained results revealed that the interface stability is determined by both the intrinsic electrochemical stability of the solid electrolyte and the passivating properties of the formed interfacial products. With appropriate material selection for stability at the respective anode and cathode interfaces, stable cycling performance can be achieved for Na all-solid-state batteries

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

Search for alternative materials for solid oxide fuel cells : syntheses and characterizations of oxyborates

Ces travaux portent sur la recherche de matériaux alternatifs d’électrolyte ou d’électrodes de piles à combustible à oxyde solide. Une méthodologie basée sur la composition de l’oxyborate La26O27(BO3)8, développé à l’IMN, a permis de mettre en évidence deux matériaux prometteurs : Ba3Ti3O6(BO3)2 et K3Sb4O10(BO3). La synthèse de poudres de Ba3Ti3O6(BO3)2 et de phases substituées sur les sites du Ba ou du Ti ont été réalisés par voie solide à 950 °C. Les mesures de conductivité ont été effectuées par EIS sur des échantillons denses (compacité ≥ 90 %). Sous air, la conductivité est purement anionique et dépasse 10-4 S.cm-1 à 700 °C. Elle augmente pour les composés substitués par un élément de valence supérieure, et inversement. Sous atmosphère hydrogénée, une forte augmentation de conductivité est observée (x 200), liée à l’apparition d’une contribution électronique. Une étude couplant DRX, XPS et ATG montre que cette contribution est due à une réduction de 5 % du Ti4+ en Ti3+ et que cette réaction est réversible. Les calculs DFT ont permis de déterminer les énergies de formation et de migration des défauts dans le matériau. L’oxyborate K3Sb4O10(BO3) a été obtenu sous forme de monocristaux et de poudre. Une étude approfondie de la densification a été nécessaire afin d’obtenir des échantillons denses (compacité ≈ 90 %), en utilisant un broyage planétaire et/ou une aide au frittage. La conductivité du matériau sous air est de l’ordre de 10-3 S.cm-1 à 700 °C. Ces travaux mettent en évidence pour la première fois des niveaux de conductivité (ioniques et/ou électroniques) importants dans les oxyborates. Cette approche peut être appliquée à la recherche de matériaux alternatifs pour SOFC.This work focuses on the search for alternative electrolyte or electrodes materials for solid oxide fuel cells. A methodology based on the composition of the La26O27(BO3)8 oxyborate, developed at the IMN, revealed two promising materials: Ba3Ti3O6(BO3)2 and K3Sb4O10(BO3). Syntheses of powders of Ba3Ti3O6(BO3)2 and substituted phases on the Ba or Ti atomic site were carried out by solid state reaction at 950 °C. Conductivity measurements were carried out by electrochemical impedance spectroscopy on dense samples (relative density ≥ 90 %). Under air, the conductivity is purely anionic and exceeds 10-4 S.cm-1 at 700 °C. Conductivity increases for compounds substituted with a supervalent element, and vice versa. In a hydrogen containing atmosphere, a large increase of conductivity is observed (x 200), linked to the appearance of an electronic contribution. A study combining XRD, XPS and TGA shows that this contribution is due to the reduction of 5 % of the Ti4+ in Ti3+ and that this reaction is reversible. DFT calculations allowed to determine the formation energies and the migration barriers of the defects in the material. K3Sb4O10(BO3) oxyborate was obtained as single crystals and powder. A thorough study of the densification of the material was necessary in order to obtain dense samples (relative density ≈ 90 %), using ball milling and/or sintering aid. The conductivity of the material in air is about 10-3 S.cm-1 at 700 °C. This work highlights significant conductivity levels (ionic and/or electronic) observed for the first time in oxyborates. This approach can be applied to find alternative materials for SOFC