A fluorine‐doped antiperovskite Li‐ion conductor Li2(OH)X (X=Cl, Br) is shown to be a promising candidate for a solid electrolyte in an all‐solid‐state Li‐ion rechargeable battery. Substitution of F− ...for OH− transforms orthorhombic Li2OHCl to a room‐temperature cubic phase, which shows electrochemical stability to 9 V versus Li+/Li and two orders of magnitude higher Li‐ion conductivity than that of orthorhombic Li2OHCl. An all‐solid‐state Li/LiFePO4 with F‐doped Li2OHCl as the solid electrolyte showed good cyclability and a high coulombic efficiency over 40 charge/discharge cycles.
Higher conductivity: A fluorine‐doped antiperovskite Li‐ion conductor Li2(OH)0.9F0.1Cl shows electrochemical stability up to 9 V versus Li+/Li and two orders of magnitude higher Li‐ion conductivity than that of orthorhombic Li2OHCl.
A subzero‐temperature cathode material is obtained by nucleating cubic prussian blue crystals at inhomogeneities in carbon nanotubes. Due to fast ionic/electronic transport kinetics even at −25 °C, ...the cathode shows an outstanding low‐temperature performance in terms of specific energy, high‐rate capability, and cycle life, providing a practical sodium‐ion battery powering an electric vehicle in frigid regions.
Selenium has been confined in the form of cyclic Se8 molecules within ordered mesoporous carbon for use as a cathode material in Li–Se batteries. An ex situ study of the Se cathode reveals conversion ...from cyclic Se8 molecules into chain‐like Sen molecules upon cycling. This effectively eliminates the shuttle effect of Se, resulting in superior electrochemical performance in terms of volumetric capacity density and cycling stability.
In overcoming the Li+ desolvation barrier for low‐temperature battery operation, a weakly‐solvated electrolyte based on carboxylate solvent has shown promises. In case of an organic‐anion‐enriched ...primary solvation sheath (PSS), we found that the electrolyte tends to form a highly swollen, unstable solid electrolyte interphase (SEI) that shows a high permeability to the electrolyte components, accounting for quickly declined electrochemical performance of graphite‐based anode. Here we proposed a facile strategy to tune the swelling property of SEI by introducing an inorganic anion switch into the PSS, via LiDFP co‐solute method. By forming a low‐swelling, Li3PO4‐rich SEI, the electrolyte‐consuming parasitic reactions and solvent co‐intercalation at graphite‐electrolyte interface are suppressed, which contributes to efficient Li+ transport, reversible Li+ (de)intercalation and stable structural evolution of graphite anode in high‐energy Li‐ion batteries at a low temperature of −20 °C.
Inclusion of difluorophosphate anion in the primary solvation sheath of a weakly‐solvated electrolyte helps to switch the swelling properties of solid electrolyte interphase (SEI) on a graphite (Gr) composite anode. By forming a low‐swelling, Li3PO4‐enriched SEI, reversible Li+ (de)intercalation was enabled at a stable Gr‐electrolyte interface, contributing to improved low‐temperature electrochemical performance of a Li‐ion battery.
In this work, we have developed a simple approach to rationally design and controllably synthesize custard-apple-like Si@N, O-dual-doped carbon with hierarchical porosity. This material delivers ...outstanding reversible capacity at high current density with good rate capability and a long cycling life of over 4000 cycles as an anode for Li-ion batteries. A detailed eletrochemical kinetic analysis reveals that the lithium ion charge storage partly depends on the capacitance-controlled behavior, with a high capacitive contribution up to 30.3% for the total capacity at 1mVs−1. The impressive eletrochemical performance demonstrates that the Si@mNOC anode has great potential to meet the challenges arising from the use of Si nanoparticles as anode for next-generation large-scale energy storage.
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•A simple method for custard-apple-like Si@N, O-dual-doped carbon is proposed.•The special N, O-doping enhances excellent electrochemical performance.•The structural stability was shown to improve cycling life.
High‐energy lithium‐ion batteries built with silicon‐based anode materials are usually associated with short cycle lives due to mechanical failure at an anode level and more importantly, due to ...electrochemical failure at a cell level as a result of irreversible consumption of cathode Li during initial charge. (Electro)chemical prelithiation has shown promises to compensate initial Li loss and improve cycling performance of the battery. However, previous strategies applied directly at anode or cathode could raise concerns on safety and degraded electrode structure, and are less compatible with industrial manufacture of batteries. Here, a new concept of prelithiation by lithiation agents supported functional separator, which is highly adaptive to electrode preparation, battery manufacture and formation, and is capable of, by simply adjusting cell voltage, not only replenishing cathode Li loss but re‐uptaking anode Li to inhibit local over‐lithiation and dendrite formation, is shown. By employing the functional separator, a 3‐Ah Li‐ion pouch cell that pairs a silicon‐based anode and a high‐nickel layered oxide cathode demonstrates stable energy output of >330 Wh kg−1 and much improved cycling performance.
A new prelithiation method based on a lithiation agents supported functional separator is proposed to compensate the Li loss during battery formation and cycling, and promises a high‐energy rechargeable lithium‐ion battery with improved safety and sustainability.
Solid‐oxide Li+ electrolytes of a rechargeable cell are generally sensitive to moisture in the air as H+ exchanges for the mobile Li+ of the electrolyte and forms insulating surface phases at the ...electrolyte interfaces and in the grain boundaries of a polycrystalline membrane. These surface phases dominate the total interfacial resistance of a conventional rechargeable cell with a solid–electrolyte separator. We report a new perovskite Li+ solid electrolyte, Li0.38Sr0.44Ta0.7Hf0.3O2.95F0.05, with a lithium‐ion conductivity of σLi=4.8×10−4 S cm−1 at 25 °C that does not react with water having 3≤pH≤14. The solid electrolyte with a thin Li+‐conducting polymer on its surface to prevent reduction of Ta5+ is wet by metallic lithium and provides low‐impedance dendrite‐free plating/stripping of a lithium anode. It is also stable upon contact with a composite polymer cathode. With this solid electrolyte, we demonstrate excellent cycling performance of an all‐solid‐state Li/LiFePO4 cell, a Li‐S cell with a polymer‐gel cathode, and a supercapacitor.
A perovskite that is stable in water with 3≤pH≤14 shows small interfacial resistance and excellent cycling performance in an all‐solid‐state Li/LiFePO4 cell, a Li‐S cell, and a supercapacitor.
Acute myocardial infarction (AMI) is one of the leading causes of death globally, with a mortality rate of over 20%. However, the diagnostic biomarkers frequently used in current clinical practice ...have limitations in both sensitivity and specificity, likely resulting in delayed diagnosis. This study aimed to identify potential diagnostic biomarkers for AMI and explored the possible mechanisms involved. Datasets were retrieved from the Gene Expression Omnibus. First, we identified differentially expressed genes (DEGs) and preserved modules, from which we identified candidate genes by LASSO (least absolute shrinkage and selection operator) regression and the SVM–RFE (support vector machine–recursive feature elimination) algorithm. Subsequently, we used ROC (receiver operating characteristic) analysis to evaluate the diagnostic accuracy of the candidate genes. Thereafter, functional enrichment analysis and an analysis of immune infiltration were implemented. Finally, we assessed the association between biomarkers and biological processes, infiltrated cells, clinical traits, tissues and time points. We identified nine preserved modules containing 1,016 DEGs and managed to construct a diagnostic model with high accuracy (GSE48060: AUC = 0.923; GSE66360: AUC = 0.973) incorporating two genes named S100A9 and SOCS3. Functional analysis revealed the pivotal role of inflammation; immune infiltration analysis indicated that eight cell types (monocytes, epithelial cells, neutrophils, CD8+ T cells, Th2 cells, NK cells, NKT cells and platelets) were likely involved in AMI. Furthermore, we observed that S100A9 and SOCS3 were correlated with inflammation, variably infiltrated cells, clinical traits of patients, sampling tissues and sampling time points. In conclusion, we suggested S100A9 and SOCS3 as diagnostic biomarkers of AMI and discovered their association with inflammation, infiltrated immune cells and other factors.
Germanium is a promising high-capacity anode material for lithium ion batteries, but it usually exhibits poor cycling stability because of its huge volume variation during the lithium uptake and ...release process. A double protection strategy to improve the electrode performance of Ge through the use of Ge@C core-shell nanostructures and reduced graphene oxide (RGO) networks has been developed. The as-synthesized Ge@C/RGO nanocomposite showed excellent cycling performance and rate capability in comparison with Ge@C nanoparticles when used as an anode material for Li ion batteries, which can be attributed to the electronically conductive and elastic RGO networks in addition to the carbon shells and small particle sizes of Ge. The strategy is simple yet very effective, and because of its versatility, it may be extended to other high-capacity electrode materials with large volume variations and low electrical conductivities.
Lithium‐sulfur batteries are promising candidates of energy storage devices. Both adjusting salt/solvent ratio and applying quasi‐solid‐state electrolytes are regarded as effective strategies to ...improve the lithium (Li) anode performance. However, reaction mechanisms and interfacial properties in quasi‐solid‐state lithium‐sulfur (QSSLS) batteries with high salt concentration are not clear. Here we utilize in‐situ characterizations and molecular dynamics simulations to unravel aforesaid mysteries, and construct relationships of electrolyte structure, interfacial behaviour and performance. The generation mechanism, formation process, and mechanical/chemical/electrochemical properties of the anion‐derived solid electrolyte interphase (SEI) are deeply explored. Li deposition uniformity and dissolution reversibility are further tuned by the sustainable SEI. These straightforward evidences and deepgoing studies would guide the electrolyte design and interfacial engineering of QSSLS batteries.
The electrochemical processes at the Li anode/electrolyte interface are disclosed in quasi‐solid‐state lithium‐sulfur batteries with high salt concentration via in‐situ atomic force microscopy and optical microscopy. The 3D morphology, local mechanics, and ion conductivity of the on‐site formed solid electrolyte interphase are in‐situ measured and analyzed to reveal the regulation effect of high salt concentration on interfacial electrochemistry.
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