Highly Effective Polyacrylonitrile-Rich Artificial Solid-Electrolyte-Interphase for Dendrite-Free Li-Metal/Solid-State Battery.

Lithium metal anode batteries have attracted significant attention as a promising energy storage technology, offering a high theoretical specific capacity and a low electrochemical potential. Utilizing lithium metal as the anode material can substantially increase energy density compared with conventional lithium-ion batteries. However, the practical application of lithium metal anodes has encountered notable challenges, primarily due to the formation of dendritic structures during cycling.

Fluorinated Artificial Solid-Electrolyte-Interphase Layer for Long-Life Sodium Metal Batteries.

Sodium metal batteries have garnered significant attention due to their high theoretical specific capacity, cost effectiveness, and abundant availability. However, the propensity for dendritic sodium formation, stemming from the highly reactive nature of the sodium metal surface, poses safety concerns, and the uncontrollable formation of the solid-electrolyte interphase (SEI) leads to large cell impedance and battery failures. In this study, we present a novel approach where we have successfully developed a stable fluorinated artificial SEI layer on the sodium metal surface by employing various weight percentages of tin fluoride in a dimethyl carbonate solution, utilizing a convenient, cost-effective, and single-step method.

Mg ion-catalyzed polymerization of 1,3-dioxolane in battery electrolytes.

Electrolyte salts with Mg2+ and Al3+ Lewis acidic cations demonstrate polymerization of 1,3-dioxolane. The speed and extent of the reaction depends on coordination of the anion with the Mg2+ cation catalyst. Weakly coordinating anions such as TFSI- aid faster polymerization while strongly coordinating anions such as ClO4- hinder the polymerization.

Electrochemically Controlled Solid Electrolyte Interphase Layers Enable Superior Li-S Batteries.

Lithium-sulfur (Li-S) batteries suffer from shuttle reactions during electrochemical cycling, which cause the loss of active material sulfur from sulfur-carbon cathodes, and simultaneously incur the corrosion and degradation of the lithium metal anode by forming passivation layers on its surface. These unwanted reactions therefore lead to the fast failure of batteries. The preservation of the highly reactive lithium metal anode in sulfur-containing electrolytes has been one of the main challenges for Li-S batteries.

Epitaxial Welding of Carbon Nanotube Networks for Aqueous Battery Current Collectors.

Carbon nanomaterials are desirable candidates for lightweight, highly conductive, and corrosion-resistant current collectors. However, a key obstacle is their weak interconnection between adjacent nanostructures, which renders orders of magnitude lower electrical conductivity and mechanical strength in the bulk assemblies. Here we report an "epitaxial welding" strategy to engineer carbon nanotubes (CNTs) into highly crystalline and interconnected structures.

[Risk factors of cubitus varus in humeral condylar fracture after conservative treatment in child].

Objective: To further investigate the risk factors of cubitus varus in humeral condylar fracture after conservative treatment in children through Logistic regression analysis, so as to guide the clinical treatment.

Methods: Children with humeral condylar fracture who were treated by manipulative reduction and plaster fixation in our hospital from March 2008 to December 2014 were studied. The clinical data including age, gender, BMI, time from injury to reduction, direction of displacement, rotation displacement, fixed position, and epiphyseal injury were collected.

Nanoscale Protection Layers To Mitigate Degradation in High-Energy Electrochemical Energy Storage Systems.

In the pursuit of energy storage devices with higher energy and power, new ion storage materials and high-voltage battery chemistries are of paramount importance. However, they invite-and often enhance-degradation mechanisms, which are reflected in capacity loss with charge/discharge cycling and sometimes in safety problems. Degradation mechanisms are often driven by fundamentals such as chemical and electrochemical reactions at electrode-electrolyte interfaces, volume expansion and stress associated with ion insertion and extraction, and profound inhomogeneity of electrochemical behavior.

Reducing Interfacial Resistance between Garnet-Structured Solid-State Electrolyte and Li-Metal Anode by a Germanium Layer.

Substantial efforts are underway to develop all-solid-state Li batteries (SSLiBs) toward high safety, high power density, and high energy density. Garnet-structured solid-state electrolyte exhibits great promise for SSLiBs owing to its high Li-ion conductivity, wide potential window, and sufficient thermal/chemical stability. A major challenge of garnet is that the contact between the garnet and the Li-metal anodes is poor due to the rigidity of the garnet, which leads to limited active sites and large interfacial resistance.

Solid Electrolyte Lithium Phosphous Oxynitride as a Protective Nanocladding Layer for 3D High-Capacity Conversion Electrodes.

Materials that undergo conversion reactions to form different materials upon lithiation typically offer high specific capacity for energy storage applications such as Li ion batteries. However, since the reaction products often involve complex mixtures of electrically insulating and conducting particles and significant changes in volume and phase, the reversibility of conversion reactions is poor, preventing their use in rechargeable (secondary) batteries. In this paper, we fabricate and protect 3D conversion electrodes by first coating multiwalled carbon nanotubes (MWCNT) with a model conversion material, RuO2, and subsequently protecting them with conformal thin-film lithium phosphous oxynitride (LiPON), a well-known solid-state electrolyte.

Next-Generation Lithium Metal Anode Engineering via Atomic Layer Deposition.

Lithium metal is considered to be the most promising anode for next-generation batteries due to its high energy density of 3840 mAh g(-1). However, the extreme reactivity of the Li surface can induce parasitic reactions with solvents, contamination, and shuttled active species in the electrolyte, reducing the performance of batteries employing Li metal anodes. One promising solution to this issue is application of thin chemical protection layers to the Li metal surface.

Directed Kinetic Self-Assembly of Mounds on Patterned GaAs (001): Tunable Arrangement, Pattern Amplification and Self-Limiting Growth.

We present results demonstrating directed self-assembly of nanometer-scale mounds during molecular beam epitaxial growth on patterned GaAs (001) surfaces. The mound arrangement is tunable via the growth temperature, with an inverse spacing or spatial frequency which can exceed that of the features of the template. We find that the range of film thickness over which particular mound arrangements persist is finite, due to an evolution of the shape of the mounds which causes their growth to self-limit.