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The conformal surface coating of Ni-rich layered cathode materials is essential for mitigating their interfacial and subsequent structural degradation. The zirconia (ZrO2) coating effectively enhances the surface stability of the cathode owing to its excellent chemical durability; however, the insulating electrical conductivity of ZrO2 increases the electrode resistance and triggers efficiency decay. Here, we propose highly conductive oxygen-deficient black ZrO2−x as a charge-conductive coating material. The black ZrO2−x is uniformly coated onto the Ni-rich LiNi0.8Mn0.1Co0.1O2 (NMC) surface via a solvent-free mechanochemical shearing process. Benefiting from the black ZrO2−x coating layer, black ZrO2−x coated NMC shows improved cycling characteristics and better rate capability than both bare NMC and ZrO2 coated NMC. The enhanced electrochemical performance by the conformal coating of black ZrO2−x mainly results from enhanced charge transfer, reduced gas evolution, and mitigated microstructural cracking. Density functional theory calculations confirm that the defective structure of black ZrO2−x lowers the energy barrier for Li ion transfer, and strong hybridization between Zr in black ZrO2−x and O in NMC mitigates oxygen evolution. [ABSTRACT FROM AUTHOR]

Lithium–oxygen (Li–O2) batteries, recognized as candidates for the highest energy storage, face challenges of irreversibility and low efficiency due to insulating discharge products. Addressing these issues, our study explores innovative dual-atom catalysts (DACs) comprising non-precious metals, specifically atomically scaled nickel (Ni) and iron (Fe), positioned on defective mesopore sites of nitrogen-doped carbon nanotubes (NCNTs) to enhance battery performance. We successfully achieved the synthesis of both homogeneous (Fe–Fe-NCNTs and Ni–Ni-NCNTs) and heterogeneous (Ni–Fe-NCNTs and Fe–Ni-NCNTs) DACs on NCNTs, by varying the loading sequences and combination of Ni and Fe. Our findings demonstrate that Fe-first-loaded DACs, particularly heterogeneous Ni–Fe-NCNT variants, excelled in both NO2− mediation reactivity and catalytic activity, achieving a longer lifespan of 200 cycles and maintaining consistent ORR/OER overpotential. Insights into the mesoporous loading sites and reaction mechanisms of these DACs in Li–O2 cells were gained through density functional theory calculations. This research paves the way for replacing costly noble metal catalysts with tailored non-noble metal combinations, potentially revolutionizing Li–O2 cell technology and broadening applications in heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

This study introduces a novel Sequence-to-Sequence (Seq2Seq) deep learning model for predicting lithium-ion batteries' remaining useful life. We address the challenge of extrapolating battery performance from high-rate to low-rate charging conditions, a significant limitation in previous studies. Experiments were also conducted on commercial cells using charge rates from 1C to 3C. Comparative analysis of fully connected neural networks, convolutional neural networks, and long short-term memory networks revealed their limitations in extrapolating to untrained conditions. Our Seq2Seq model overcomes these limitations, predicting charging profiles and discharge capacity for untrained, low-rate conditions using only high-rate charging data. The Seq2Seq model demonstrated superior performance with low error and high curve-fitting accuracy for 1C and 1.2C untrained data. Unlike traditional models, it predicts complete charging profiles (voltage, current, temperature) for subsequent cycles, offering a comprehensive view of battery degradation. This method significantly reduces battery life testing time while maintaining high prediction accuracy. The findings have important implications for lithium-ion battery development, potentially accelerating advancements in electric vehicle technology and energy storage. [ABSTRACT FROM AUTHOR]

Although all‐solid‐state batteries are suggested as a means to tackle the safety concerns associated with current Li‐ion batteries, there is presently a lack of comprehensive understanding regarding their thermal safety. In this context, critical factors contributing to the thermal runaway of thiophosphate solid electrolytes with charged Li1‐xNi0.8Co0.1Mn0.1O2 (NCM) under thermal and mechanical abuse conditions are demonstrated, considering parameters such as heating rate under thermal abuse conditions and the hybridization of S atom in structure. In particular, the thermal behavior of various solid electrolytes, including thiophosphates, thioantimonates, and halides, is investigated to clarify critical elements in Li6PS5Cl (LPSCl) contributing to its thermal instability when combined with charged NCM. Various ex situ analyses, along with density functional theory calculations, reveal a correlation between the hybridization of S atoms and the thermal instability of solid electrolytes, suggesting that sulfur acts as a key element triggering the thermal runaway of sulfide‐based solid electrolytes. [ABSTRACT FROM AUTHOR]

Graphite is used as an anode material in commercial lithium-ion batteries (LIBs) because of its stable cycling characteristics and high reversibility. However, during fast charging, the deposition of Li metal on the graphite electrode surface becomes problematic because the potential at which Li metal deposition occurs would be close to 0 V (vs. Li/Li+). In this study, we demonstrated an improvement in the fast-charging performance through the effective suppression of Li deposition on the anode surface during fast charging. This was achieved by introducing a metal phosphide nanodot coating layer onto artificial graphite particles. Through various analyses, including density functional theory (DFT) calculations, it was found that the cobalt phosphide(CoP) coating layer increased the concentration of PF6− anions in the inner Helmholtz layer (IHL), which in turn induced the formation of an anion-derived solid-electrolyte interface (SEI) layer. A CoP-artificial graphite (AG)/NCM 811 full cell exhibited a high capacity retention (88%) after 300 cycles, without any Li deposition. We also verified the impact of other types of metal phosphides on the fast-charging performance of LIBs. Our findings suggest that the rational design of the SEI layer is feasible through simple surface modifications that induce changes in the properties of the electric double layer. This provides a novel perspective for the design of materials suitable for the rapid charging of LIBs. [ABSTRACT FROM AUTHOR]

Reframing ionic transport and interface chemistry through electrolyte renovation is essential to promote the fast charging of Li-ion batteries, even under extreme conditions. Despite the formation of a less resistive interface using high-concentration electrolytes (HCEs), their inevitably high viscosity compromises their practical use. This work aims to explore the most suitable hydrofluoroether diluents for localized-high-concentration electrolytes (LHCEs). Contrary to the consensus on their negligible intervention in the Li+ solvation sheath, experimental evidence, and simulation studies have revealed that diluents can partially penetrate solvation and enable intermolecular interactions with solvents and additives. While the extent of physical intervention is similar, the intermolecular binding becomes greater when using longer-chain diluents with increased –CF2– moieties, hindering the desired interfacial reactions. By strategically selecting smaller diluents with fewer –CF2– units, low-viscosity LHCEs can attain the long stable cycling of Li-ion cells at a 10 minute charging rate (∼18 mA cm−2) over 500 cycles, and facilitate reliable performance under demanding conditions, such as thick electrodes (∼5 mAh cm−2) and low temperatures (−20 °C). [ABSTRACT FROM AUTHOR]

Lithium (Li) metal, with its unparalleled theoretical capacity and lowest electrochemical potential, is a promising anode material for rechargeable batteries. Yet, challenges such as dendrite formation, severe electrode volume change, and ongoing Li consumption impede its practical adoption. To address these challenges, a novel approach is introduced, harnessing the switchable electrical conductivity of a nanoporous current collector for Li metal anode. A vertically aligned Nickel‐catecholate (VANC) is directly grown on the copper foil as the nanoporous current collector, and the Li intercalation and de‐intercalation of VANC reversibly decrease and increase the electrical conductivity in the direction perpendicular to the electrode, respectively. The switchable conductivity induces uniform deposition and stripping of Li metal without forming dendrite and dead Li during the Li plating/stripping process and thus enables high coulombic efficiency of over 98% even after 200 cycles. This nanoporous structure with switchable conductivity will open up a new path for reliable lithium metal anode for rechargeable battery applications. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) have drawn significant attention owing to their high theoretical discharge capacity and energy density. However, the dissolution of long‐chain polysulfides into the electrolyte during the charge and discharge process ("shuttle effect") results in fast capacity fading and inferior electrochemical performance. In this study, Mn2O3 with an ordered mesoporous structure (OM‐Mn2O3) was designed as a cathode host for LSBs via KIT‐6 hard templating, to effectively inhibit the polysulfide shuttle effect. OM‐Mn2O3 offers numerous pores to confine sulfur and tightly anchor the dissolved polysulfides through the combined effects of strong polar–polar interactions, polysulfides, and sulfur chain catenation. The OM‐Mn2O3/S composite electrode delivered a discharge capacity of 561 mA h g−1 after 250 cycles at 0.5 C owing to the excellent performance of OM‐Mn2O3. Furthermore, it retained a discharge capacity of 628 mA h g−1 even at a rate of 2 C, which was significantly higher than that of a pristine sulfur electrode (206 mA h g−1). These findings provide a prospective strategy for designing cathode materials for high‐performance LSBs. [ABSTRACT FROM AUTHOR]

With the growing popularity of Li‐ion batteries in large‐scale applications, building a safer battery has become a common goal of the battery community. Although the small errors inside the cells trigger catastrophic failures, tracing them and distinguishing cell failure modes without knowledge of cell anatomy can be challenging using conventional methods. In this study, a real‐time, non‐invasive magnetic field imaging (MFI) analysis that can signal the battery current‐induced magnetic field and visualize the current flow within Li‐ion cells is developed. A high‐speed, spatially resolved MFI scan is used to derive the current distribution pattern from cells with different tab positions at a current load. Current maps are collected to determine possible cell failures using fault‐simulated batteries that intentionally possess manufacturing faults such as lead‐tab connection failures, electrode misalignment, and stacking faults (electrode folding). A modified MFI analysis exploiting the magnetic field interference with the countercurrent‐carrying plate enables the direct identification of defect spots where abnormal current flow occurs within the pouch cells. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) are in the spotlight as a next‐generation battery due to their high theoretical capacity. However, LMBs still suffer from inferior cycle stability owing to dendritic lithium (Li) growth during Li plating and stripping, leading to battery explosion. To solve this problem, solid electrolytes have emerged as a promising candidate by suppressing the dendritic Li growth. Despite numerous efforts, however, many challenges, such as low ionic conductivity, air stability, space charge layer, and contact loss issues, have been encountered. This review aims to provide the current challenges and new insights of solid electrolytes and then explore optimal solutions for next‐generation solid electrolytes. [ABSTRACT FROM AUTHOR]

All-solid-state Li-ion batteries (ASSBs) are considered as ideal next-generation energy storage devices owing to their safe operation and high energy densities. Recently, halide-based solid electrolytes (SEs) have come under the spotlight because of their wide electrochemical stability windows and high ionic conductivities. However, their usage as coating materials for cathodes is limited. To examine the wide electrochemical stability window of SEs for lithium-metal anodes and their interfacial stability with high-voltage cathodes, a systematic first-principles investigation of A-site cation and anion exchange in Li3MX6 (M: Lu, Sc, Bi, In, Y, Tm, Dy, Ho, Er, Tm, Sm, Tb; X: Br, Cl, and I) was conducted. The systematic analysis showed that the electrochemical behavior of chloride SEs can be modulated by mixing M3+ cations. Furthermore, the replacement of M3+ by Zr4+ and the anionic blending of Br with Cl, which exhibits a relatively high ionic conductivity, was also computed for comparison with the A-site cation-mixed halide electrolyte. Our computational work provides an overview of the evolution of lithium halide SEs in high-voltage ASSBs. [ABSTRACT FROM AUTHOR]

Introducing dielectric materials is a promising approach to mitigate space‐charge‐layer (SCL) formation, which negatively affects the electrochemical performance of sulfide‐based all‐solid‐state batteries (ASSBs). Most previous studies have focused on mitigating SCL formation by introducing dielectric materials, overlooking the fact that significant dielectric properties such as the dipole moment direction and the magnitude of the dielectric constant can influence SCL formation. To clarify the unclear mechanism of dielectric materials mitigating SCL formation, paraelectricity, ferroelectricity, and the magnitude of the dielectric constant are investigated to determine their effect on SCL formation. Paraelectric materials possessing no permanent dipole moment can effectively mitigate the SCL formation better than ferroelectric material with strong permanent dipole moment because of the intrinsic characteristics of the paraelectric material, in which the dipole moment can be aligned along the direction of the electric field applied inside of ASSB. Furthermore, paraelectric materials with a larger dielectric constant have a greater effect in mitigating SCL effect than paraelectric materials with a smaller dielectric constant. Thus, these properties should be considered in cathode‐solid‐electrolyte interface design. This study considers relevant dielectric material characteristics that had not been considered previously, suggesting a new paradigm for optimizing the interfacial resistance of sulfide‐based ASSBs originating from SCL formation. [ABSTRACT FROM AUTHOR]

In this study, microwave irradiation is employed for the phenolation of acid-insoluble Klason lignin. Microwave irradiation significantly reduces the reaction temperature (180 → 100 °C) and time (6 h → 10 min) without noticeable differences in the chemical structure of the phenolated lignin compared with the products prepared using a conventional heating method. As the reaction temperature increases (100 → 150 °C), lignin decomposition and crosslinking occur simultaneously, as did phenolation. Upon increasing the phenol-to-lignin ratio, the fragmentation of lignin is enhanced, while the crosslinking reaction is inhibited, leading to a decrease in the molecular weight and glass transition temperature of the phenolated lignin. Density functional theory is applied to elucidate the thermal and non-thermal effects of the electromagnetic field on the phenolation of Klason lignin. The solubility of Klason lignin in tetrahydrofuran and methanol is highly enhanced after phenolation, which allows for its adhesive application on glass, polyethylene naphthalate, and polyimide substrates. [ABSTRACT FROM AUTHOR]

The structural engineering of crystal frameworks has emerged as a highly useful technique in the development of perovskite solar cells (PSCs) to realize highly efficient devices with superior chemical and electrical properties. The introduction of organic spacer cations into perovskite crystals is one of the major topics currently being explored in the field of structural engineering research. However, intercalated organic molecules in three-dimensional (3D) perovskite structures generate low-dimensional perovskite phases, resulting in inefficient carrier transport due to a reduction in 3D dimensionality. Maintaining the 3D crystal structures of organic-cation-inserted perovskites remains a major issue and a challenging task to be solved. In this work, we created an ideal organic-layered 3D crystal structure using an n-butylammonium (n-BA) halide salt in a FA0.83Cs0.17Pb0.5Sn0.5I3 perovskite. The cation allows a self-assembled hierarchical structure in which the n-BA organic analog is layered on the surface and at the bottom of the perovskite without a reduction of the 3D crystal dimensionality. Based on X-ray scattering results, the existence of a vertically oriented crystal structure, from both external and internal structural perspectives, demonstrates the creation of an ideal n-BA-capped 3D perovskite crystal. Furthermore, the self-assembling n-BA cations facilitate an enhancement of the device stability of Pb–Sn PSCs, due to the suppression of the generation of silver iodide at the top interface and the degradation of PSS in poly(3,4-ethylenedioxythiophene)polystyrene sulfonate (PEDOT:PSS) by sulfuric acid at the bottom interface. These structural and chemical stability effects lead to the creation of a highly efficient Pb–Sn PSC with nearly 19% efficiency. [ABSTRACT FROM AUTHOR]

Utilization of lithium (Li) metal anode is highly desirable for achieving high energy density batteries. Even so, the unavoidable features of Li dendritic growth and inactive Li are still the main factors that hinder its practical application. During plating and stripping, the solid electrolyte interphase (SEI) layer can provide passivation, playing an important role in preventing direct contact between the electrolyte and the electrode in Li metal batteries. Because of complexities of the electrolyte chemical and electrochemical reactions, the various formation mechanisms for the SEI are still not well understood. What we do know is that a strategic artificial SEI achieved through additives electrolyte can suppress the Li dendrites. Otherwise, the dendrites keep generating an abundance of irreversible Li, resulting in severe capacity loss, internal short‐circuiting, and cell failure. In this minireview, we focus on the phenomenon of dendritic Li‐growth and provide a brief overview of SEI formation. We finally provide some clear insights and perspectives toward practical application of Li metal batteries. [ABSTRACT FROM AUTHOR]

The utilization of lithium (Li) metal is highly desirable, because it is the most attractive anode for high-energy Li batteries, even if there are problems with the unpredictable phenomena of dendritic growth and dead-Li during repeated plating-stripping. So far, the issue of branch-like uneven Li plating has still not been resolved. Recently, using a highly concentrated salt-electrolyte (lithium bis(fluorosulfonyl with a LiNO3 additive)) was recognized as the most straightforward approach, although its critical role still remains elusive. Herein, we investigated the overpotential of metallic Li anodes with electrolytes having different salt concentrations and verified the microscopic origins of Li growth, as observed by in situ optical microscopy. We argue that the high ionic conductivity of the electrolyte together with its solid-state interphase effectively suppresses the local potential and concentration gradients, resulting in highly dense dendrite-free Li plating, as supported by in-depth numerical analysis. Our findings provide clear insights that can pave the way to further improvements of the performance of Li metal anodes up to the theoretical limit (3860 mA h g−1). [ABSTRACT FROM AUTHOR]