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Sodium metal batteries (NMBs) have attracted increasing attention as next‐generation rechargeable batteries. How to improve their cycling stability and safety under limited sodium excess conditions, ideally zero sodium excess (i.e., anode‐free architecture), is highly desired yet remains challenging. Herein, it is demonstrated that sodium formate (HCOONa), one component of the solid electrolyte interphase (SEI) naturally formed on sodium metal anode, is a promising candidate for designing high‐performance artificial SEI layers, which can suppress the sodium dendrite formation and reduce the side reactions between sodium and the electrolyte. Profiting from the HCOONa interface, the Na|Na3V2(PO4)3 battery with a high mass loading of Na3V2(PO4)3 (10 mg cm−2) exhibits a superior cycling stability with an ultralow decay rate of 0.004% per cycle over 800 cycles. More impressively, a single molecular layer of HCOONa in situ formed on commercial copper current collector helps to extend the lifespan of the anode‐free Cu|Na3V2(PO4)3 battery to 400 cycles with 88.2% capacity relation, representing the longest cycle lifetime reported in anode‐free NMBs. [ABSTRACT FROM AUTHOR]

Organic room‐temperature long‐persistent luminescent materials are promising light‐emitting materials for encryption, architectural decoration, organic solar cells, and biomedical applications. However, their unstable structures and thermal‐ and humidity‐induced emission quenching have greatly limited their utility and reliability. Here, we report a metal‐free nonconjugated copolymer that possesses stable photoluminescence at both high temperature and humidity. The room‐temperature long‐persistent luminescence (LPL) of this copolymer lasts for more than 15 s and can be recovered in high humidity conditions by heating to remove moisture. Copolymer LPL can be achieved with various excitation wavelengths, ranging from ultraviolet to near‐infrared, and the LPL color can be adjusted accordingly. The high initial LPL intensity and ultrafast filling time of the copolymer makes it suitable for low flicker alternating current‐driven light‐emitting diodes (AC‐LEDs). [ABSTRACT FROM AUTHOR]

All‐solid‐state thin‐film lithium batteries (TFLBs) are the ideal wireless power sources for on‐chip micro/nanodevices due to the significant advantages of safety, portability, and integration. As the bottleneck for increasing the energy density of TFLBs, the key components of cathode, electrolyte, and anode are still underway to be improved. In this review, a brief history of TFLBs is first outlined by presenting several TFLB configurations. Based on the state‐of‐the‐art materials developed for lithium‐ion batteries (LIBs), the challenges and related strategies for the application of those potential electrode and electrolyte materials in TFLBs are discussed. Given the advanced manufacture and characterization techniques, the recent advances of TFLBs are reviewed for pursuing the high‐energy‐density and long‐term‐durability demands, which could guide the development of future TFLBs and analogous all‐solid‐state lithium batteries. [ABSTRACT FROM AUTHOR]

Solid‐state lithium batteries (SSLBs) are promising owing to enhanced safety and high energy density but plagued by the relatively low ionic conductivity of solid‐state electrolytes and large electrolyte–electrode interfacial resistance. Herein, we design a poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP)‐based polymer‐in‐salt solid electrolyte (PISSE) with high room‐temperature ionic conductivity (1.24×10−4 S cm−1) and construct a model integrated TiO2/Li SSLB with 3D fully infiltration of solid electrolyte. With forming aggregated ion clusters, unique ionic channels are generated in the PISSE, providing much faster Li+ transport than common polymer electrolytes. The integrated device achieves maximized interfacial contact and electrochemical and mechanical stability, with performance close to liquid electrolyte. A pouch cell made of 2 SSLB units in series shows high voltage plateau (3.7 V) and volumetric energy density comparable to many commercial thin‐film batteries. [ABSTRACT FROM AUTHOR]

Abstract: To address the serious capacity fading in lithium–sulfur batteries, a 3D ferroconcrete‐like aminated carbon nanotubes network with polyaniline coating as an effective sulfur host to contain polysulfide dissolution is presented here. In this composite, the cross‐linked aminated carbon nanotubes framework provides a fast charge transport pathway and enhancement in the reaction kinetics of the active material to greatly improve the rate capability and sulfur utilization. The ethylenediamine moieties provide strong adhesion of polar discharge products to nonpolar carbon surfaces and thus efficiently prevent polysulfide dissolution to improve the cycle stability, confirmed by density functional theory calculations. The outside polyaniline layers structurally restrain polysulfides to prevent the shuttle effect and active material loss. Benefiting from these advantages, the synthesized composite exhibits a high initial capacity of 1215 mAh g−1 and a capacity of 975 mAh g−1 after 200 cycles at 0.2 C. Even after 200 cycles at 0.5 C, a capacity of 735 mAh g−1 can be maintained, among the best performance reported. The strategy in this work can shed some light on modifying nonpolar carbon surfaces via the amination process to chemically attach sulfur species for high‐performance lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

In this article, a new morphing method is proposed for two linear features at different scales, based on their entire structures ( MLBES in abbreviation). First, the bend structures of the linear features are identified by using a constrained Delaunay triangulation ( CDT in abbreviation) model and represented by binary bend-structure trees. By matching the independent bends represented by the bend-structure trees, corresponding independent bends are obtained. These corresponding independent bends are further used to match their child bends based on hierarchical bend structures so that corresponding bends are obtained. On this basis, the two linear features are split into pairs of corresponding subpolylines by the start and end points of the corresponding bends. Second, structures of the corresponding subpolylines are identified by the Douglas- Peucker algorithm and represented by binary line generalization trees ( BLG-trees in abbreviation). The corresponding subpolylines are split into smaller corresponding subpolylines by matching the nodes of the BLG-trees. Third, the corresponding points are identified by using the linear interpolation algorithm for every pair of corresponding subpolylines. Finally, straight-line trajectories are employed to generate a family of intermediate-scale linear features. By comparison with other methods, it is found that MLBES is accurate and efficient. [ABSTRACT FROM AUTHOR]