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Since their commercialization in the 1990s, lithium-ion batteries (LIBs) have been increasingly used in applications such as portable electronics, electric vehicles, and large-scale energy storage. The increasing use of LIBs in modern society has necessitated superior-performance LIB development, including electrochemical reversibility, interfacial stability, efficient kinetics, environmental adaptability, and intrinsic safety, which is difficult to simultaneously achieve in commercialized electrolytes. Current electrolyte systems contain a solution with Li salts (e.g., LiPF6) and solvents (e.g., ethylene carbonate and dimethyl carbonate), in which the latter dissolves Li salts and strongly interacts with Li+(lithiophilic feature). Only lithiophilic agents can be functionally modified (e.g., additives and solvents), altering the bulk and interfacial behaviors of Li+solvates. However, such approaches alter pristine Li+solvation and electrochemical processes, making it difficult to strike a balance between the electrochemical performance and other desired electrolyte functions. This common electrolyte design in lithiophilic solvents shows strong coupling among formulation, coordination, electrochemistry, and electrolyte function. The invention of lithiophobic cosolvents (e.g., multifluorinated ether and fluoroaromatic hydrocarbons) has expanded the electrolyte design space to lithiophilic (interacts with Li+) and lithiophobic (interacts with solvents but not with Li+) dimensions. Functional modifications switch to lithiophobic cosolvents, affording superior properties (carried by lithiophobic cosolvents) with little impact on primary Li+solvation (dictated by lithiophilic solvents). This electrolyte engineering technique based on lithiophobic cosolvents is the 2D electrolyte (TDE) principle, which decouples formulation, coordination, electrochemistry, and function. The molecular-scale understanding of TDEs is expected to accelerate electrolyte innovations in next-generation LIBs.

By leveraging the loose coordination between Li+and CPME, the developed electrolyte supports fast Li+desolvation and maintains ultra-high lithium metal anode compatibility simultaneously for −60 oC lithium metal batteries operation.

Safety issues related to flammable electrolytes in lithium-ion batteries (LIBs) remain a major challenge for their extended applications. The use of non-flammable phosphate-based electrolytes has proved the validity in inhibiting the combustion of LIBs. However, the strong interaction between Li+and phosphate leads to a dominant solid electrolyte interphase (SEI) with limited electronic shielding, resulting in the poor Li+intercalation at the graphite (Gr) anode when using high-phosphate-content electrolytes. To mitigate this issue and improve Li+insertion, we propose an “In-N-Out” strategy to render phosphates “non-coordinative”. By employing a combination of strongly polar solvents for a “block effect” and weakly polar solvents for a “drag effect”, we reduce the Li+-phosphate interaction. As a result, phosphates remain in the electrolyte phase (“In”), minimizing their impact on the incompatibility with the Gr electrode (“Out”). We have developed a non-flammable electrolyte with high triethyl phosphate (TEP) content (>60 wt.%), demonstrating the excellent ion conductivity (5.94 mS cm −1at 30 °C) and reversible Li+intercalation at a standard concentration (~1 mol L −1). This approach enables the manipulation of multiple electrolyte functions and holds the promise for the development of safe electrochemical energy storage systems using non flammable electrolytes.

A EC-free electrolyte is formulated by pairing F3B with PC/EMC system, in which the non-solvating 1,3,5-trifluorobenzene (F3B) is introduced to exert solvation protection, guaranteeing high-voltage stability, wide-temperature adaptability and interfacial compatibility in lithium-ion batteries.

Pursuing high-energy-density lithium metal batteries (LMBs) necessitates the advancement of electrolytes. Despite demonstrating high compatibility with lithium metal anodes (LMAs), ether-based electrolytes face challenges in achieving stable cycling at high voltages. Herein, we propose a strategy to enhance the high-voltage stability of medium-concentration (∼1 M) ether electrolytes by altering the reaction pathway of ether solvents. By employing a 1 M lithium difluoro(oxalato)borate in dimethoxyethane (LiDFOB/DME) electrolyte, we observed that LiDFOB displays a pronounced tendency for decomposition over DME, leading to a modification in the decomposition pathway of DME. This modification facilitates the formation of a stable organic–inorganic hybrid interface. Utilizing such an electrolyte, the Li-LCO cell demonstrates a discharge specific capacity of 146 mAh g–1(5 C) and maintains retention of 86% over 1000 cycles at 2 C under a 4.5 V cutoff voltage. Additionally, the optimized ether electrolyte demonstrated outstanding cycling performance in Li-LCO full cells under practical conditions.

Irreversible lithium loss in the initial cycles appreciably reduces the energy density of lithium-ion batteries. Prelithiation is an effective way to compensate for such lithium loss, but current methods suffer from either the instability or low capacity of prelithiation reagents. Lithium oxalate (Li2C2O4) has shown great potential as a lithium-compensation material because of its high theoretical capacity (equivalent to lithium metal), low cost, and air stability. However, the practical applications of Li2C2O4are limited by its low electrochemical activity and high critical decomposition voltage. In this study, we performed the prelithiation of a low-voltage cathode by using Mo2C catalysis and nano-Li2C2O4. Results show that the Mo2C catalyst changes the electron cloud distribution around Li2C2O4and greatly reduces the activation energy, thereby significantly accelerating the lithium release from Li2C2O4. The nano-Li2C2O4prepared by freeze-drying shows accelerated ionic and electronic conduction as well as close contact with Mo2C. Benefiting from the synergistic effect, the decomposition potential of Li2C2O4is decreased by 0.5 V with an efficiency close to 100%. The LiCoO2∥SiO full cell empowered with the nano-Li2C2O4/Mo2C prelithiation composite demonstrates 46.9% higher capacity than the control and thus has great potential for practical applications.

The existing transmission line detection technologies based on cloud computing are faced with the problems such as low response speed, high communication cost, and difficulty in obtaining scattered data. This article proposes a transmission line defect detection method based on adaptive federated learning (FL), which can adaptively change the data volume of the next training round according to the training energy consumption of each round. As a result, the proposed method can achieve the optimal number of communication between local training cost and global communication efficiency, which greatly improves the training speed and reduces the communication cost. Furthermore, a lightweight Mask region-convolutional neural network (R-CNN) that adopts the MobileNet architecture to replace the original network is designed for the edge, which reduces the required number of parameters and improves the detection speed. The experimental results show that the model training efficiency of the proposed adaptive FL is 70% higher than the centralized cloud computing, and the computing cost is saved by about 40%. Compared with the original Mask R-CNN, the proposed lightweight Mask R-CNN model can achieve 1.1% higher precision, 10% shorter training time, and 40% faster detection speed.

Polysaccharides from Fuzhuan brick tea (FBTPS), one of most important bioactive components in tea, showed various health-promoting functions. Our previous work demonstrated that the crude FBTPS (CFBTPS) could modulate the gut microbiota. However, which purified fraction in CFBTPS contributing to the modulation of gut microbiota remains unclear. Thus, the fermentation characteristics and probiotic activity of a purified fraction (FBTPS-2-1) of CFBTPS were evaluated in this work. The results showed that gut microbiota could utilize FBTPS-2-1 to produce short-chain fatty acids including acetic, propionic, n-butyric and n-valeric acids. FBTPS-2-1 could modulate the structure and metabolic pathways of gut microbiota. FBTPS-2-1 could increase the health-promoting gut microbiota such as Prevotellaceae and Bifidobacteriaceae, and decreased the harmful bacteria such as Enterobacteriaceae and Fusobacteriaceae. The results of metagenomics showed that Prevotella copriand Megamonas funiformiswere the dominant bacteria after fermentation of FBTPS-2-1. Furthermore, FBTPS-2-1 could regulate the biosynthesis and metabolism pathways of gut microbiota. Thus, the enrichment of food with FBTPS-2-1 is expected as a potential strategy for promoting human health due to modulation of gut microbiota.

Three-dimensional (3D) current collectors can effectively mitigate the volumetric expansion of working lithium metal anodes (LMAs). However, the practical utilization of 3D current collectors for lithium metal batteries remains unsatisfactory because of inhomogeneous deposition of lithium ions and an unstable solid electrolyte interphase (SEI). Herein, a facile method based on the exchange reaction between Li and AgNO3is exploited to embed Ag nanoparticles (NPs) and LiNO3in a carbon paper (ALCP@Li). The Ag NPs act as a seed for even lithium deposition inside the carbon matrix by virtue of their excellent lithiophilicity. Simultaneously, LiNO3plays an effective role in stabilizing LMAs by evolving a robust N-rich SEI. As a result, such 3D LMAs show a high Coulombic efficiency in half-cells (200 cycles, 99% at 1 mA cm–2, 1 mAh cm–2) and a low overpotential (60 mV). When paired with commercial thick NCM622 and LiFePO4cathodes, the 3D LMA-based full cells exhibit stable cycling in carbonate electrolytes.

Fuzhuan brick tea (FBT), one of the unique dark teas, has various health-promoting functions. In the present study, one polysaccharide fraction, namely FBTPS-2-1, was extracted and purified from FBT, and its structure and potential immunostimulatory activity were investigated. The results showed that FBTPS-2-1,one of typical heteropolysaccharides, was mainly composed of Gal, Ara, and Glc with little molar content of Man, Rha, GalA, and GlcA in molar ratio of 46.59:22.13:13.57:8.20:6.02:2.12:1.38 and molecular weight of 748 kDa. The backbone of FBTPS-2-1 contained →4)-β-d-Galp-(1→4)-β-d-Galp-(1→, →4)-β-d-Galp-(1→4)-α-d-Glcp-(1→, →4)-α-d-Glcp-(1→4)-α-d-Glcp-(1→, →4)-α-d-Glcp-(1→4)-β-d-Galp-(1→, →3)-β-d-Galp-(1→4)-β-d-Galp-(1→, →3,6)-β-d-Galp-(1→3)-β-d-Galp-(1→ and →3,6)-β-d-Galp-(1→3,6)-β-d-Galp-(1→. The linkages of branches in FBTPS-2-1 were mainly composed of α-l-Araf-(1→3,6)-β-d-Galp-(1→, →5)-α-l-Araf-(1→3,6)-β-d-Galp-(1→, →6)-β-d-Galp-(1→3,6)-β-d-Galp-(1→, α-l-Araf-(1→3,5)-α-l-Araf-(1→, →3,5)-α-l-Araf-(1→5)-α-l-Araf-(1→, α-d-Galp-(1→3,5)-α-l-Araf-(1→ and →5)-α-l-Araf-(1→6)-β-d-Galp-(1→. Furthermore, FBTPS-2-1 could increase the phagocytosis of macrophages and promote the secretion of NO and a variety of inflammatory cytokines, including TNF-α, IL-1β, and IL-6, indicating noticeable immune enhancement activity. Thus, FBTPS-2-1 could serve as a potentially functional food to improve human health by modulating the host immunoreaction.

An ultrathick lithium metal anode (LMA) is a prerequisite for developing practical lithium–sulfur (Li–S) batteries that simultaneously meet the requirements of high areal capacity, lean electrolyte, and limited excess Li. Inspired by the electrochemical process for an organosulfur cathode, herein, we reconfigure such a sulfur cathode by using an overlithiation strategy to enable the formation of a high performance LMA. Specifically, an applicable ultrathick LMA is successfully constructed by overlithiating a well-known organosulfur cathode material, sulfurized polyacrylonitrile (SPAN). SPAN contains a polymeric pyridine structure with an outstanding lithium-ion affinity, so that it can act as a lithiophilic matrix. More importantly, a Li2S-rich solid electrolyte interphase (SEI) can be generated on the surface of SPAN during the overlithiation process. The synergistic effect of the lithiophilic matrix and a robust SEI leads to a dense deposition of lithium, which enables one to form an ultrathick LMA (159 μm, 30 mAh cm–2) with high Coulombic efficiency (99.7%). Such an LMA paired with a sulfur cathode of high areal capacity (up to 16 mAh cm–2) shows stable cycling under practical conditions of a lean electrolyte (2.2 μL mgS–1) and a negative-to-positive capacity (N/P) ratio as low as 1.3. The applicability of the ultrathick LMA was further verified with Li–S pouch cells, indicating a highly prospective route toward realization of practical Li–S batteries.

Practical applications of lithium metal anodes are gravely impeded by inhomogeneous lithium deposition, which results in dendrite growth. Electrolyte additives are proven to be effective in improving performance but usually serve only a single function. Herein, nitrofullerene is introduced as a bifunctional additive with a smoothing effect and forms a protective solid electrolyte interphase (SEI) layer on stable lithium metal anodes. By design, nitro-C60can gather on electrode protuberances via electrostatic interactions and then be reduced to NO2–and insoluble C60. Next, the C60anchors on the uneven groove of the lithium surface, resulting in a homogeneous distribution of Li ions. Finally, NO2–anions can react with metallic Li to build a compact and stable SEI with high ion transport. With a 5 mM nitro-C60additive, Li–Li symmetric cells show superior cycle stability in both carbonate and ether electrolytes, Li–sulfur batteries with a high cathode loading (10.6 mg cm–2, 6 mAh cm–2) can achieve improved cycle retention of 63.2% over 100 cycles in a carbonate electrolyte, and full cells paired with a high-areal-capacity LiNi0.6Co0.2Mn0.2O2cathode (3.5 mAh cm–2) exhibit a significantly enhanced cycle lifespan even under lean electrolyte conditions.

The pairing of lithium metal anode (LMA) with Ni-rich layered oxide cathodes for constructing lithium metal batteries (LMBs) to achieve energy density over 500 ​Wh ​kg−1receives significant attention from both industry and the scientific community. However, notorious problems are exposed in practical conditions, including lean electrolyte/capacity (E/C) ratio (< 3 ​g ​(Ah)−1), high cathode mass loading (> 3 ​mAh ​cm−2), and low negative/positive (N/P) ratio (< 3), which creates a significant disparity between the current performance of LMBs and the desired requirements for commercial applications. In the review, we present a summary of the recent achievements made in understanding the mechanistic degradation of LMA, followed by practical strategies that are utilized to address these issues. We also consider the detrimental issues of Ni-rich layered oxide cathodes. Furthermore, we highlight current progresses in the field of practical LMBs in coin/pouch cells to stimulate further innovation. In the end, we propose the issues and prospects for development from the perspective of practical LMBs.

The self-sacrificing Li2C2O4is a promising lithium replenisher benefiting from its high specific capacity, residue-free and low-cost properties. However, the intrinsic low electrochemical activity leads to a decomposition potential up to 4.7 V, posing a challenge for the compatibility of electrolyte and cathode materials. Herein, a three-dimensional (3D) hierarchical spherical Mo2C/N-doped graphene co-catalysts is synthesized by self-polymerization and high-temperature annealing. It is shown that the synergistic catalytic effect of Mo2C and N-doped activated graphene enhances the reactivity of Li2C2O4and the hierarchical three-dimensional conducting network accelerates the electron-ion transport. When the nano-Li2C2O4is homogeneously encapsulated in the spherical catalytic center using a freeze-drying technique, the electrochemical reaction of Li2C2O4is greatly promoted, resulting a significant drop of decomposition potential from 4.7 V to 4.16 V. As a result, the specific capacity of Gr||LFP and SiC||LFP full cells with composite lithium replenisher can be increased by 15% and 22%, respectively. Moreover, the solid electrolyte interface (SEI) is appropriately strengthened with pre-lithiation and thus guarantees superior cycling performance.

Bell's palsy is the most common form of facial nerve palsy. This study aimed to explore the pathogenesis of Bell's palsy by investigating the effect of cold-stimulated adipocyte supernatant on adhesion molecule expression in Schwann cell line. Schwann cells were cultured in regular or adipocyte-conditioned medium and analyzed using RNA sequencing. The mRNA expression of Schwann cell adhesion molecules melanoma cell adhesion molecule (MCAM), protocadherin 9 (PCDH9), and intercellular cell adhesion molecule 1 (ICAM1) was determined using real-time reverse-transcription polymerase chain reaction. Differentially expressed genes were identified, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were conducted. Compared with Schwann cells in 37 °C, the expression of MCAM, PCDH9, and ICAM1 was downregulated in Schwann cells treated with cold-stimulated adipocyte supernatant compared with Schwann cells in 37 °C. Adipocytes subjected to cold exposure may weaken the adhesion capacity of Schwann cells and disrupt the local homeostasis of Schwann cell–axon interactions by affecting the expression of MCAM, PCDH9, and ICAM1, ultimately leading to the development of demyelinating lesions.

Nonflammable phosphate electrolytes are in principle able to build intrinsically safe Na-ion batteries, but their electrochemical incompatibility with anodic materials, especially hard carbon anode, restricts their battery applications. Here, we propose a new strategy to enable high-capacity utilization and cycle stability of hard carbon anodes in the nonflammable phosphate electrolyte by using low-cost Na+salt with a high molar ratio of salt/solvent combined with an solid electrolyte interphase film-forming additive. As a result, the carbon anode in the trimethyl phosphate (TMP) electrolyte with a high molar ratio of [NaClO4]/[TMP] and 5% fluoroethylene carbonate additive demonstrates a high reversible capacity of 238 mAh g–1, considerable rate capability, and long-term cycling life with 84% capacity retention over 1500 cycles. More significantly, this work provides a promising route to build intrinsically safe and low-cost sodium-ion batteries for large-scale energy storage applications.

Development of intrinsically safe and long lifespan sodium-ion batteries (SIBs) is urgently needed for large-scale energy storage applications. However, most of the currently developed SIBs suffer from insufficient cycle life and potential unsafety. Herein, we construct an all-phosphate sodium-ion battery (AP-SIB) using a Na3V2(PO4)3cathode, NaTi2(PO4)3anode, and nonflammable trimethyl phosphate (TMP) electrolyte. The AP-SIB exhibits not only high safety, high rate performance, and ultralong cycle life but also zero-strain characteristics due to the inverse volume change of the phosphate cathode and anode during charge and discharge cycles, offering a safer and cycle-stable Na-ion technology for electric storage applications.

The intracellular polysaccharides of Aspergillus cristatus(IPSs) from Fuzhuan brick tea have been demonstrated to improve immune function linked to modulating the gut microbiota. Herein, to further investigate the efficacy of IPSs to maintain gut homeostasis, the protection of the purified fraction of IPSs (IPSs-2) on the mice with colitis induced by dextran sulfate sodium (DSS) and the underlying mechanisms were explored in this study. The results revealed that IPSs-2 alleviated the typical symptoms of colitis and suppressed the excessive inflammatory mediators, regulating the genes related to inflammatory responses in the colon at the mRNA level. Meanwhile, IPSs-2 treatment reinforced the intestinal barrier function by ameliorating the DSS-induced histological injury, facilitating the differentiation of goblet cells to enhance Mucin-2 generation, and enhancing the expression of tight junction proteins to alleviate colitis. In addition, IPSs protected against colitis by promoting the production of short-chain fatty acids (SCFAs), the activation of SCFAs receptors, and the leverage of the gut microbiota viathe enrichment of Bacteroides, Parabacteroides, Faecalibacterium, Flavonifractor_plautii, and Butyricicoccus, linking with reducing inflammation and repairing intestinal barrier function. Overall, our research revealed the therapeutic potential of IPSs-2 as a prebiotic for attenuating inflammatory bowel disease and provided a rationale for future investigation.

Long charging times and poor low-temperature performance are two major challenges that hamper the widespread use of lithium-ion batteries in electrical devices. The electrolyte plays an important role in determining the charging time and operating temperature of batteries. Herein we demonstrate a weakly-solvating electrolyte consisting of 2.0 M lithium bis(fluorosulfonyl)imide in acetonitrile with fluorobenzene as the cosolvent. This combination is superior in terms of balancing the solvation/de-solvation of an electrolyte which simultaneously yields enhanced diffusion of Li+in the bulk electrolyte and improved kinetics of Li+de-solvation. In addition, we achieve a rapid interfacial diffusion of Li+at the inorganic–polymeric solid electrolyte interphase, derived from fluorobenzene. Graphite half cells show a high specific capacity of 302.7 mA h g−1at 8 C, long-term cycle life (91% retention after 1000 cycles at 5 C), and remarkable low temperature performance. Moreover, the NCM811 | graphite pouch cells also exhibit outstanding performance for fast-charging (201 mA h g−1at 0.5 C and 167 mA h g−1at 5 C) as well as outstanding cycling stability (80% retention after 500 cycles at 5 C). In summary, we provide design principles and experimental demonstration of next-generation electrolytes capable of fast charging and low-temperature operation.

No pressure: The oxidation of aromatic CH bonds at room temperature was realized through a copper‐catalyzed “oxygenase‐type” oxidation of arenes and heteroarenes in the presence of air (see scheme). The reaction involves an oxygen‐atom transfer from O2in the air onto the substrates.

Kein Druck: Die Oxidation aromatischer C‐H‐Bindungen bei Raumtemperatur gelingt durch eine kupferkatalysierte „Oxygenase‐artige“ Oxidation von Arenen und Heteroarenen in Gegenwart von Luft (siehe Schema). Die Reaktion umfasst einen Sauerstoffatomtransfer vom O2der Luft auf das Substrat.

Any species that can attack S–S bonds and produce more electrochemically active M–S bonds could potentially serve as a mediator.

Over-lithiated organosulfides, such as sulfurized polyacrylonitrile (SPAN), are promising candidates of lithium metal anode (LMA) protection since they could form robust solid electrolyte interphases (SEIs), which is the key toward stable lithium metal batteries. So far, the mechanism of over-lithiation and evolution of the electrode surface is poorly understood. Herein, several in situ techniques were employed to study the over-lithiation process in SPAN, including in situ Raman spectroscopy to reveal the chemical transformation and in situ electrochemical atomic force microscopy (EC-AFM) to visualize interfacial evolution. The results undoubtedly prove the breaking of the C–S bond and formation of the C–Li bond during the over-lithiation process. The nucleophilic C–Li could further trigger the decomposition of the electrolyte to form an inorganic–organic hybrid SEI on the surface of SPAN, which allows uniform Li deposition and significantly improves the cycle stability of LMAs, as supported by the in situ EC-AFM characterization as well as a series of full cell tests. New insights into the over-lithiation mechanism of SPAN should facilitate the design of organosulfides to construct stable lithium metal anodes.

The design of solid polymer electrolytes (SPE) with high ionic conductivity and excellent mechanical properties is challenging because these two properties are often conflicting. To achieve both, a reaction-controlled strategy is proposed based on the nanophase separation of an ionic transport pathway and a supporting matrix to balance ionic mobility and mechanical properties. Specifically, an elastic epoxy polymer electrolyte (eEPE), synthesized via two-step polymerization, combines outstanding mechanical strength (toughness of 3.4 MJ m–3) and high ionic conductivity (3.5 × 10–4S cm–1at 25 °C). The nanostructured eEPE is both tough and flexible, therefore promotes uniform deposition of Li even under a high current density (2 mA cm–2and 2 mAh cm–2). Importantly, eEPE composite films greatly improve the safety performance of the LiFePO4/Li pouch cells: safe operations are achieved under several abusive conditions. This work highlights an alternative route for high-safety solid-state lithium metal batteries of the next generation.