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The quest for smart electronics with higher energy densities has intensified the development of high‐voltage LiCoO2 (LCO). Despite their potential, LCO materials operating at 4.7 V faces critical challenges, including interface degradation and structural collapse. Herein, we propose a collective surface architecture through precise nanofilm coating and doping that combines an ultra‐thin LiAlO2 coating layer and gradient doping of Al. This architecture not only mitigates side reactions, but also improves the Li+ migration kinetics on the LCO surface. Meanwhile, gradient doping of Al inhibited the severe lattice distortion caused by the irreversible phase transition of O3−H1−3−O1, thereby enhanced the electrochemical stability of LCO during 4.7 V cycling. DFT calculations further revealed that our approach significantly boosts the electronic conductivity. As a result, the modified LCO exhibited an outstanding reversible capacity of 230 mAh g−1 at 4.7 V, which is approximately 28 % higher than the conventional capacity at 4.5 V. To demonstrate their practical application, our cathode structure shows improved stability in full pouch cell configuration under high operating voltage. LCO exhibited an excellent cycling stability, retaining 82.33 % after 1000 cycles at 4.5 V. This multifunctional surface modification strategy offers a viable pathway for the practical application of LCO materials, setting a new standard for the development of high‐energy‐density and long‐lasting electrode materials. [ABSTRACT FROM AUTHOR]

LiNi0.8Co0.1Mn0.1O2 (NCM811) is a promising cathode material for lithium-ion batteries due to its high energy density and low cost. However, NCM811 suffers from poor cycling stability and storage sensitivity to air and moisture. This study introduces an AlF3 protective layer onto the surface of NCM811 (NCM811-AlF3) by atomic layer deposition (ALD). After the AlF3 layer protection, the initial capacity of the quasi-solid-state pouch cell with the NCM811 cathode was significantly increased from 148 to 180 mAh g−1. In addition, NCM811-AlF3 maintained a capacity of 167 mAh g−1, which exceeded that of pristine NCM811 (126 mAh g−1) after 500 cycles. This excellent electrochemical performance is attributed to the conformal AlF3 protective layer that prevents the NCM811 from coming into direct contact with the electrolyte. In addition, the AlF3 protective layer can prevent the Li/Ni mixture and Li loss during cycling by limiting the lattice expansion. Moreover, it can suppress the generation of residual alkali on the NCM811 surface during storage, improving the interfacial stability between NCM811 and the electrolytes. These results indicate that AlF3 protective layer by ALD can be an effective method for improving the performance of high-energy–density cathode materials. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) are considered as promising high energy density batteries. However, they still suffer from poor cyclability due to the instability of solid electrolyte interphases (SEIs) and Li dendrite issues. Herein, a novel 3D densely packed multifunctional crosslinked gel polymer electrolyte (PHGPE) has been synthesized by in situ copolymerization of pentaerythritol tetraacrylate and 2-hydroxyethyl acrylate in a liquid electrolyte via a thermal initiation method. Due to intermolecular hydrogen bonding in the frameworks, the PHGPE exhibits a 3D compact-stacked and crosslinked micro-sphere structure, which benefits the construction of homogeneous Li+ flux, enabling uniform Li plating/stripping and formation of robust SEIs onto the lithium electrode. Benefiting from the above advantages, symmetric Li cells in the PHGPE deliver excellent cyclabilities of 6000 h at a current density of 1 mA cm−2 (1 mA h cm−2) and 7700 h at 0.5 mA cm−2 (2 mA h cm−2). Moreover, the PHGPE has such a wide electrochemical window that it is compatible with both high-voltage LiNi0.8Co0.1Mn0.1O2 and sulfur cathodes to realize long cycle life. Additionally, a LiFePO4 based pouch size LMB also presents promising performance. Therefore, this study of the PHGPE has opened a new avenue for high-performance LMBs with excellent versatility and practicality. [ABSTRACT FROM AUTHOR]

Transition metal oxides (TMOs)‐based anode materials of high theoretical capacities have been intensively studied for lithium‐ion storage. However, their poor high‐rate capability and cycling stability remain to be effectively resolved. Herein, a novel ion exchange (IE)‐assisted indirect carbon coating strategy is proposed to realize high performance freestanding TMO‐based anodes for flexible lithium‐ion batteries (FLIBs). This approach effectively avoids the possible side reaction of oxide reduction, enhances degrees of graphitization of the carbon coating, and preserves advantageous nanostructure of the starting template, leading to enhanced electrical conductivities, alleviated volume variation induced structural instability, fast lithium‐ion diffusion pathways and enhanced electron transfer kinetics. As a proof of concept, IE‐prepared carbon coated NiO nanosheet arrays with excellent structural and electrochemical stability are developed as freestanding anodes for LIBs and FLIBs, which exhibit outstanding electrochemical performances superior to most state‐of‐the‐art NiO‐based anodes reported in recent years. The product anode delivers a high areal capacity (3.08 mAh cm−2 at 0.25 mA cm−2), outstanding high‐rate capability (1.78 mAh cm−2 at 8 mA cm−2) and excellent cycling stability (over 300 cycles). Further pouch cell tests confirm the excellent flexibility of the freestanding electrode against mechanical deformation with well‐maintained electrochemical performance under folding. [ABSTRACT FROM AUTHOR]

A biodiesel production process using magnetically stabilized fluidized bed reactor (MSFBR) has been developed based on the refined cottonseed oil. The reactant flow rate and magnetic field intensity effects on the nanometer magnetic catalyst behavior in the column were investigated. Orthogonal experiments (L(2)) were applied to optimize the best transesterification reaction conditions. Reaction temperature, methanol to oil molar ratio, and reactant flow rate were the main factors to influence transesterification conversion efficiency. These three factors chosen for the present investigation were based on the results of single-factor tests. The optimum transesterification reaction conditions of cottonseed oil were determined in MSFBR as follows: methanol to oil molar ratio 8:1, 40 cm min reactant flow rate, 225 Oe magnetic field intensity and reaction temperature of 65 °C, the conversion efficiency reached 97% in 100 min. The cold filter plugging point and kinematic viscosity of cottonseed oil biodiesel were higher than that described by Chinese specifications of biodiesel because of the special fatty acid profiles of cottonseed oil. The activity stability of the nanometer magnetic solid catalyst in MSFBR was much better than that in the autoclave stirred reactor (ASR). [ABSTRACT FROM AUTHOR]

• V 2 O 5 nanobelt arrays are firstly used as the lithiophilic materials. • This Li-V 2 O 5 -NF composite anode displays superior Li stripping/platting behavior. • The LTO/Li-V 2 O 5 -NF cells display superior rate performance and cycling stability. The lithium metal anode has been considered to be an optimal anode material for high-energy-density battery system due to its ultrahigh specific capacity. However, the sharp dendrite growth and infinite volume expansion have significantly impeded its commercial application. Herein, we propose that V 2 O 5 as the lithiophilic substance can be decorated onto 3D stable frameworks to fabricate dendrite-suppressed composite Li metal anodes via a molten Li infusion method. It is demonstrated that the energetic chemical reaction between V 2 O 5 and molten Li together with the capillary effect based on the nanostructure of interconnected V 2 O 5 nanobelt arrays contributes synergistically to the great Li affinity of the V 2 O 5 -Ni foam (V 2 O 5 -NF) host and facilitate the efficient and uniform intake of molten Li into the 3D framework. Benefitting from the homogeneous Li distribution in the framework, the decreased local current density of the electrode and the stable property of the host, dendrite-free Li stripping/plating behavior and alleviated volume fluctuation have been achieved for the Li-V 2 O 5 -NF composite anode. Compared with the bare Li anode, the as-obtained Li-V 2 O 5 -NF composite anode exhibits much stable stripping/plating profiles with low overpotential (~18 mV) for ultralong lifespan (1600 h) at a current density of 1 mA cm−2 in symmetric Li/Li cell. Furthermore, outstanding rate capability and long-term cycling performance (78.8% capacity retention after 500 cycles under 2 C) are obtained in full cells when coupled with Li 4 Ti 5 O 12 (LTO) cathodes, indicating a promising potential for practical application. Moreover, this work demonstrates that using a new lithiophilic material, V 2 O 5 , should be an effective method to construct high stable 3D Li metal anode for Li metal battery. [ABSTRACT FROM AUTHOR]

The linseed gum/cellulose composite hydrogels were successfully fabricated by mixing cellulose and linseed gum solutions dissolved in the NaOH/urea aqueous system and cross-linked with epichlorohydrin. The morphology and structure of the composite hydrogels were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD) and thermogravimetric analysis (TGA). The swelling ratio and water retention properties were investigated. The results revealed that linseed gum mainly contributed to water adsorption, whereas the cellulose acted as a backbone to strengthen the porous structure. This work provided a simple way to prepare cellulose-based superabsorbent hydrogels, which could be potentially applied as an effective water conservation material in agriculture. [ABSTRACT FROM AUTHOR]

The quest for smart electronics with higher energy densities has intensified the development of high-voltage LiCoO 2 (LCO). Despite their potential, LCO materials operating at 4.7 V faces critical challenges, including interface degradation and structural collapse. Herein, we propose a collective surface architecture through precise nanofilm coating and doping that combines an ultra-thin LiAlO 2 coating layer and gradient doping of Al. This architecture not only mitigates side reactions, but also improves the Li + migration kinetics on the LCO surface. Meanwhile, gradient doping of Al inhibited the severe lattice distortion caused by the irreversible phase transition of O3-H1-3-O1, thereby enhanced the electrochemical stability of LCO during 4.7 V cycling. DFT calculations further revealed that our approach significantly boosts the electronic conductivity. As a result, the modified LCO exhibited an outstanding reversible capacity of 230 mAh g -1 at 4.7 V, which is approximately 28 % higher than the conventional capacity at 4.5 V. To demonstrate their practical application, our cathode structure shows improved stability in full pouch cell configuration under high operating voltage. LCO exhibited an excellent cycling stability, retaining 82.33 % after 1000 cycles at 4.5 V. This multifunctional surface modification strategy offers a viable pathway for the practical application of LCO materials, setting a new standard for the development of high-energy-density and long-lasting electrode materials., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)