Cation valency in water-in-salt electrolytes alters the short- and long-range structure of the electrical double layer.

Highly concentrated aqueous electrolytes (termed water-in-salt electrolytes, WiSEs) at solid-liquid interfaces are ubiquitous in myriad applications including biological signaling, electrosynthesis, and energy storage. This interface, known as the electrical double layer (EDL), has a different structure in WiSEs than in dilute electrolytes. Here, we investigate how divalent salts [zinc bis(trifluoromethylsulfonyl)imide, Zn(TFSI)], as well as mixtures of mono- and divalent salts [lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) mixed with Zn(TFSI)], affect the short- and long-range structure of the EDL under confinement using a multimodal combination of scattering, spectroscopy, and surface forces measurements.

Chemical Origin of in Situ Carbon Dioxide Outgassing from a Cation-Disordered Rock Salt Cathode.

In situ carbon dioxide (CO) outgassing is a common phenomenon in lithium-ion batteries (LiBs), primarily due to parasitic side reactions at the cathode-electrolyte interface. However, little is known about the chemical origins of the in situ CO released from emerging Li-excess cation-disordered rock salt (DRX) cathodes. In this study, we selectively labeled various carbon sources with C in cathodes containing a representative DRX material, LiMnTiO (LMTO), and performed differential electrochemical mass spectrometry (DEMS) during galvanostatic cycling in a carbonate-based electrolyte.

An Experimental Approach to Assess Fluorine Incorporation into Disordered Rock Salt Oxide Cathodes.

Disordered rock salt oxides (DRX) have shown great promise as high-energy-density and sustainable Li-ion cathodes. While partial substitution of oxygen for fluorine in the rock salt framework has been related to increased capacity, lower charge-discharge hysteresis, and longer cycle life, fluorination is poorly characterized and controlled. This work presents a multistep method aimed at assessing fluorine incorporation into DRX cathodes, a challenging task due to the difficulty in distinguishing oxygen from fluorine using X-ray and neutron-based techniques and the presence of partially amorphous impurities in all DRX samples.

Lithium-Ion Transport and Exchange between Phases in a Concentrated Liquid Electrolyte Containing Lithium-Ion-Conducting Inorganic Particles.

Understanding Li transport in organic-inorganic hybrid electrolytes, where Li has to lose its organic solvation shell to enter and transport through the inorganic phase, is crucial to the design of high-performance batteries. As a model system, we investigate a range of Li-conducting particles suspended in a concentrated electrolyte. We show that large LiAlTiPO and LiPSCl particles can enhance the overall conductivity of the electrolyte.

The Tokyo 2020 and Beijing 2022 Olympic Games held during the COVID-19 pandemic: planning, outcomes, and lessons learnt.

The COVID-19 pandemic profoundly affected all mass gatherings for sporting and religious events, causing cancellation, postponement, or downsizing. On March 24, 2020, the Japanese Government, the Tokyo Organising Committee of the Olympic and Paralympic Games, and the International Olympic Committee decided to postpone the Tokyo 2020 Olympic and Paralympic Games until the summer of 2021. With the emergence of SARS-CoV-2, the potential creation of a superspreading event that would overwhelm the Tokyo health system was perceived as a risk.

A Critical Analysis of Chemical and Electrochemical Oxidation Mechanisms in Li-Ion Batteries.

Electrolyte decomposition limits the lifetime of commercial lithium-ion batteries (LIBs) and slows the adoption of next-generation energy storage technologies. A fundamental understanding of electrolyte degradation is critical to rationally design stable and energy-dense LIBs. To date, most explanations for electrolyte decomposition at LIB positive electrodes have relied on ethylene carbonate (EC) being chemically oxidized by evolved singlet oxygen (O) or electrochemically oxidized.

Nonintrusive thermal-wave sensor for operando quantification of degradation in commercial batteries.

Monitoring real-world battery degradation is crucial for the widespread application of batteries in different scenarios. However, acquiring quantitative degradation information in operating commercial cells is challenging due to the complex, embedded, and/or qualitative nature of most existing sensing techniques. This process is essentially limited by the type of signals used for detection.

Enhanced Electrochemical Performance of Disordered Rocksalt Cathodes Enabled by a Graphite Conductive Additive.

Cobalt-free cation-disordered rocksalt (DRX) cathodes are a promising class of materials for next-generation Li-ion batteries. Although they have high theoretical specific capacities (>300 mA h/g) and moderate operating voltages (∼3.5 V vs Li/Li), DRX cathodes typically require a high carbon content (up to 30 wt %) to fully utilize the active material which has a detrimental impact on cell-level energy density.

Ion correlation and negative lithium transference in polyelectrolyte solutions.

Polyelectrolyte solutions (PESs) recently have been proposed as high conductivity, high lithium transference number () electrolytes where the majority of the ionic current is carried by the electrochemically active Li-ion. While PESs are intuitively appealing because anchoring the anion to a polymer backbone selectively slows down anionic motion and therefore increases , increasing the anion charge will act as a competing effect, decreasing . In this work we directly measure ion mobilities in a model non-aqueous polyelectrolyte solution using electrophoretic Nuclear Magnetic Resonance Spectroscopy (eNMR) to probe these competing effects.

Tuning Bulk Redox and Altering Interfacial Reactivity in Highly Fluorinated Cation-Disordered Rocksalt Cathodes.

Lithium-excess, cation-disordered rocksalt (DRX) materials have been subject to intense scrutiny and development in recent years as potential cathode materials for Li-ion batteries. Despite their compositional flexibility and high initial capacity, they suffer from poorly understood parasitic degradation reactions at the cathode-electrolyte interface. These interfacial degradation reactions deteriorate both the DRX material and electrolyte, ultimately leading to capacity fade and voltage hysteresis during cycling.

Middle East respiratory syndrome coronavirus-a 10-year (2012-2022) global analysis of human and camel infections, genomic sequences, lineages, and geographical origins.

Objectives: The World Health Organization priority zoonotic pathogen Middle East respiratory syndrome (MERS) coronavirus (CoV) has a high case fatality rate in humans and circulates in camels worldwide.

Methods: We performed a global analysis of human and camel MERS-CoV infections, epidemiology, genomic sequences, clades, lineages, and geographical origins for the period January 1, 2012 to August 3, 2022. MERS-CoV Surface gene sequences (4061 bp) were extracted from GenBank, and a phylogenetic maximum likelihood tree was constructed.

Particle Surface Cracking Is Correlated with Gas Evolution in High-Ni Li-Ion Cathode Materials.

High-Ni layered oxide cathode materials (LiNiTMO, where > 0.8) are of great interest because they offer increased capacity compared to current commercial materials within a narrow voltage range. However, recent studies have shown that these materials in their current form suffer from capacity fading when an upper cutoff voltage above 4.

Impact of Platinum Primary Particle Loading on Fuel Cell Performance: Insights from Catalyst/Ionomer Ink Interactions.

A variety of electrochemical energy conversion technologies, including fuel cells, rely on solution-processing techniques (via inks) to form their catalyst layers (CLs). The CLs are heterogeneous structures, often with uneven ion-conducting polymer (ionomer) coverage and underutilized catalysts. Various platinum-supported-on-carbon colloidal catalyst particles are used, but little is known about how or why changing the primary particle loading (PPL, or the weight fraction of platinum of the carbon-platinum catalyst particles) impacts performance.

COVID-19 and other respiratory tract infections at mass gathering religious and sporting events.

Purpose Of Review: Mass gathering (MG) religious events provide ideal conditions for transmission and globalization of respiratory tract infections (RTIs). We review recent literature on COVID-19 and other RTIs at recurring international annual MG religious and sporting events.

Recent Findings: Due to the COVID-19 pandemic organizers of MG religious and sporting events introduced risk-based infection control measures that limited transmission of RTIs.

Single-Crystal LiNi Mn Co O Cathodes for Extreme Fast Charging.

Ni-rich layered LiNi Mn Co O (NMCs, x ≥ 0.8) are poised to be the dominating cathode materials for lithium-ion batteries for the foreseeable future. Conventional polycrystalline NMCs, however, suffer from severe cracking along the grain boundaries of primary particles and capacity loss under high charge and/or discharge rates, hindering their implementation in fast-charging electric vehicular (EV) batteries.

Interplay between Cation and Anion Redox in Ni-Based Disordered Rocksalt Cathodes.

The reversibility of the redox processes plays a crucial role in the electrochemical performance of lithium-excess cation-disordered rocksalt (DRX) cathodes. Here, we report a comprehensive analysis of the redox reactions in a representative Ni-based DRX cathode. The aim of this work is to elucidate the roles of multiple cations and anions in the charge compensation mechanism that is ultimately linked to the electrochemical performance of Ni-based DRX cathode.

Layered-rocksalt intergrown cathode for high-capacity zero-strain battery operation.

The dependence on lithium-ion batteries leads to a pressing demand for advanced cathode materials. We demonstrate a new concept of layered-rocksalt intergrown structure that harnesses the combined figures of merit from each phase, including high capacity of layered and rocksalt phases, good kinetics of layered oxide and structural advantage of rocksalt. Based on this concept, lithium nickel ruthenium oxide of a main layered structure (R[Formula: see text]m) with intergrown rocksalt (Fm[Formula: see text]m) is developed, which delivers a high capacity with good rate performance.