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Highlights Cellulose elementary fibrils (CEFs), the most fundamental unit of cellulose, are proposed as a deagglomerated binder for high-mass-loading Li battery electrodes. The CEFs, due to their increased surface area and anionic charge density, promote uniform dispersion with carbon additives and mitigate interfacial side reactions in electrodes. The CEF-based overlithiated layered oxide cathode exhibits a high areal-mass-loading (50 mg cm–2) and a high specific energy density (445.4 Wh kg–1) of a cell.

Abstract The pulverization of silicon (Si) anode materials is recognized as a major cause of their poor cycling performance, yet a mechanistic understanding of this degradation from a full cell perspective remains elusive. Here, we identify an overlooked contributor to Si anode failure: mechanical shutdown of separators. Through mechano-structural characterization of Si full cells, combined with digital-twin simulation, we demonstrate that the volume expansion of Si exerts localized compressive stress on commercial polyethylene separators, leading to pore collapse. This structural disruption impairs ion transport across the separator, exacerbating redox nonuniformity and Si pulverization. Compression simulation reveals that a Young’s modulus greater than 1 GPa is required for separators to withstand the volume expansion of Si. To fulfill this requirement, we design a high modulus separator, enabling a high-areal-capacity pouch-type Si full cell to retain 88% capacity after 400 cycles at a fast charge rate of 4.5 mA cm−2.

Abstract Medical plastic-appliance-based healthcare services, especially in dentistry, generate tremendous amounts of plastic waste. Given the physiological features of our mouth, it is desirable to substitute dental care plastics with viscoelastic and antimicrobial bioplastics. Herein, we develop a medical-grade and sustainable bioplastic that is viscoelastic enough to align the tooth positions, resists microbial contamination, and exhibits recyclable life cycles. In particular, we devise a molecular template involving entanglement-inducing and antimicrobial groups and prepare a silk fibroin-based dental care bioplastic. The generated compactly entangled structure endows great flexibility, toughness, and viscoelasticity. Therefore, a satisfactory orthodontic outcome is accomplished, as demonstrated by the progressive alignment of male rabbit incisors within the 2.5 mm range. Moreover, the prepared bioplastic exhibits resistance to pathogenic colonization of intraoral microbes such as Streptococcaceae and Veillonellaceae. Because the disentanglement of entangled domains enables selective separation and extraction of the components, the bioplastic can be recycled into a mechanically identical one. The proposed medical-grade and sustainable bioplastic could potentially contribute to a green healthcare future.

Highlights 1. A class of solvent-free covalent organic framework (COF) single-ion conductors (Li-COF@P) has been designed via ion–dipole interaction as opposed to traditional ion–ion interaction, promoting ion dissociation and Li+ migration through directional ionic channels. 2. The Li-COF@P enabled long cycle life (88.3% after 2000 cycles) in all-solid-state Li organic batteries (ASSLOBs) under ambient operating conditions, which outperformed those of previously reported ASSOLBs. 3. This Li-COF@P strategy holds promise as a viable alternative to the currently prevalent inorganic solid electrolytes.

The rapid growth of miniaturized electronics has led to an urgent demand for microscale energy storage devices (MESDs) to sustainably power the micro electronic devices. However, most MESDs reported to date have suffered from the limited energy densities and shape versatility compared to conventional large-scale counterparts because of the architectural constraints inherent in microfabrication-based cell manufacturing and cell dimension/structure. This review addresses the cell architecture design for MESDs that can achieve both miniaturization and high energy density. We provide a comprehensive overview of five types of cell architectures of MESDs and their fabrication techniques. In addition, to enable practical applications of MESDs, several cell design approaches are presented with the aim of minimizing the inactive parts of the cell and maximizing the performance metrics of MESDs. Finally, we discuss development direction and outlook of MESDs with a focus on materials chemistry, energy-dense electrochemical systems, and cell performance normalization, which will help to expand their applications and manufacturing scalability.

Abstract Despite the enormous interest in high-areal-capacity Li battery electrodes, their structural instability and nonuniform charge transfer have plagued practical application. Herein, we present a cationic semi-interpenetrating polymer network (c-IPN) binder strategy, with a focus on the regulation of electrostatic phenomena in electrodes. Compared to conventional neutral linear binders, the c-IPN suppresses solvent-drying-induced crack evolution of electrodes and improves the dispersion state of electrode components owing to its surface charge-driven electrostatic repulsion and mechanical toughness. The c-IPN immobilizes anions of liquid electrolytes inside the electrodes via electrostatic attraction, thereby facilitating Li+ conduction and forming stable cathode–electrolyte interphases. Consequently, the c-IPN enables high-areal-capacity (up to 20 mAh cm–2) cathodes with decent cyclability (capacity retention after 100 cycles = 82%) using commercial slurry-cast electrode fabrication, while fully utilizing the theoretical specific capacity of LiNi0.8Co0.1Mn0.1O2. Further, coupling of the c-IPN cathodes with Li-metal anodes yields double-stacked pouch-type cells with high energy content at 25 °C (376 Wh kgcell −1/1043 Wh Lcell –1, estimated including packaging substances), demonstrating practical viability of the c-IPN binder for scalable high-areal-capacity electrodes.

Highlights Mechanistic understanding of ion transport phenomena in composite solid-state electrolytes (CSEs) for practical solid-state batteries is conducted. Percolation threshold formation of the inorganic (LPSCl) phase in the CSEs depends on elasticity of the gel polymer electrolyte (GPE) phase. Manipulating the solvation/desolvation behavior of the GPE phase facilitates ion conduction across the LPSCl-GPE interfaces.

Aqueous zinc batteries (AZBs) have garnered attention as a low-cost and safe alternative to commercial lithium-ion batteries. However, the use of aqueous electrolytes has plagued electrochemical performance of AZBs particularly at sub-zero temperatures, which has hindered the expansion of their applications. Most previous studies have focused on the weakening of hydrogen bonds between water molecules, with little attention to the underlying intermolecular interactions such as dipole−dipole, dipole−ion, and ion−ion. Here, we review the design principles of low-temperature electrolytes for practical AZBs based on the mechanistic insights into the relevant intermolecular interactions, in addition to the previously prevalent approaches of hydrogen bond regulation. The electrokinetic phenomena behind the sluggish ion transport in the bulk electrolytes and the limited charge transfer at the electrode−electrolyte interface below freezing temperatures are described together with the theoretical elucidation. Based on this understanding, key determinants for the low-temperature aqueous electrolytes and their contribution to the electrochemical performance of AZBs are discussed in terms of intermolecular interactions. Lastly, we suggest the development directions and outlook of the low-temperature aqueous electrolytes, with a focus on elucidation of atomic-scale intermolecular interactions, electrode−electrolyte interface engineering, electrolyte restructuring, and cell design and electrolyte requirements for practical energy-dense AZB applications.

Scalable dry electrode process is essential for the sustainable manufacturing of the lithium based batteries. Here, the authors propose a dry press-coating technique to fabricate a robust and flexible high loading electrode for lithium pouch cells.

Purpose To compare the computerized Greulich-Pyle based bone age with elbow bone age. Materials and Methods A total of 2126 patients (1525 girls; 601 boys) whose elbow bone age was within the evaluable range by the Sauvegrain method, and who simultaneously underwent hand radiography, were enrolled in the study. The 1st-bone age and VUNO score of the hand were evaluated using VUNOMed-BoneAge software. The correlation between the hand and elbow bone age was analyzed according to the child’s gender and the probability of 1st-bone age. Results The correlation between VUNO score and elbow bone age (r = 0.898) was higher than the correlation between 1st-bone age and elbow bone age (r = 0.879). Moreover, the VUNO score showed a better correlation with the elbow bone age in patients with a 1st-bone age probability of less than 70%, or in girls. Elbow bone age was more advanced compared to hand bone age, and this difference increased until the middle of puberty and gradually decreased in the latter half. Conclusion The computerized Greulich-Pyle based hand bone age showed a significant correlation with the elbow bone age at puberty. However, since the elbow bone age tends to advance faster than the hand bone age, caution is required while judging the bone age during puberty.

The development of high energy lithium metal batteries is affected by the mass loading of the cathode. Here, the authors report a lithium metal pouch cell with a cathode capacity of 12 mAh cm-2. The positive electrode is prepared by applying UV-curable gel electrolyte as a processing solvent.

Abstract Despite the ever‐increasing demand for transparent power sources in wireless optoelectronics, most of them have still relied on synthetic chemicals, thus limiting their versatile applications. Here, a class of transparent nanocellulose paper microsupercapacitors (TNP‐MSCs) as a beyond‐synthetic‐material strategy is demonstrated. Onto semi‐interpenetrating polymer network‐structured, thiol‐modified transparent nanocellulose paper, a thin layer of silver nanowire and a conducting polymer (chosen as a pseudocapacitive electrode material) are consecutively introduced through microscale‐patterned masks (which are fabricated by electrohydrodynamic jet printing) to produce a transparent conductive electrode (TNP‐TCE) with planar interdigitated structure. This TNP‐TCE, in combination with solid‐state gel electrolytes, enables on‐demand (in‐series/in‐parallel) cell configurations in a single body of TNP‐MSC. Driven by this structural uniqueness and scalable microfabrication, the TNP‐MSC exhibits improvements in optical transparency (T = 85%), areal capacitance (0.24 mF cm−2), controllable voltage (7.2 V per cell), and mechanical flexibility (origami airplane), which exceed those of previously reported transparent MSCs based on synthetic chemicals.

Abstract Improving the volumetric capacitance of graphene materials for supercapacitors without sacrificing their rate capability, especially at high mass‐loading, is a challenge because of the sluggish electrochemical kinetics of compact graphene electrodes. Here, a compact graphene monolith (dense graphene ribbons [DGRs]‐0.6) was fabricated by using graphene oxide ribbons as building blocks and deliberately harmonizing the graphene primitive unit structure and interlayer spacing. The DGRs‐0.6 contained abundant oxygen‐containing functional groups and a highly interconnected pore structure, resulting in a large ion‐accessible surface area, a high packing density, and fast electron/ion transport pathways. The DGRs‐0.6 electrode exhibited a volumetric capacitance of 316 F cm–3, a rate capability of 220 F cm–3 at 100 A g–1, and ultralong cycling stability. For a mass loading of 11 mg cm−2, the DGRs‐0.6 delivered volumetric capacitances of 150 F cm−3 at 1 A g−1 and 109 F cm−3 at 50 A g−1. The good rate capability and volumetric capacitance of DGRs‐0.6 under high mass loading demonstrate its potential as a supercapacitor electrode for practical applications.

Rechargeable calcium batteries are promising multivalent battery systems but the lack of suitable electrodes hampers their development. Here the authors report a cathode derived from polyanion framework that demonstrates uncommonly stable and fast intercalation behaviours of calcium ions.

Abstract Despite the extensive investigation on solid‐state lithium‐metal batteries (SSLMBs), their application in flexible electronic devices has been plagued mainly by the physicochemical/mechanical instability of their electrode–electrolyte interfaces. Here, we present a fibrous skeleton‐framed, quasi‐solid‐state LMB (fs‐QSSLMB) as a new cell architecture concept to simultaneously achieve the high‐energy‐density, mechanical flexibility, and safety. The fs‐QSSLMB is fabricated by embedding poly(ethylene terephthalate) (PET) nonwovens, stainless‐steel meshes, and metal‐coated conductive PET nonwovens with a lithiophilic‐gradient morphology as customized fibrous skeletons into quasi‐solid‐state electrolytes (QSSEs), high‐capacity LiNi0.8Co0.1Mn0.1O2 (NCM811) cathodes, and Li metal anodes, respectively. The stepwise printing of the NCM811 cathode/QSSE/Li anode assembly and the subsequent one‐pot ultraviolet curing of the gel electrolyte precursors in the assembly enable the formation of seamless interfaces between the electrodes and QSSE, thereby ensuring the electrochemical sustainability and mechanical deformability of the fs‐QSSLMB. In addition, owing to its fibrous skeleton‐based structural uniqueness and seamless interfaces, the fs‐QSSLMB exhibits electrochemical reliability, mechanical flexibility, safety (i.e., electrochemically active after being vertically cut in half and exposed to flame), and high (cell‐based) gravimetric/volumetric energy densities (385 Wh kgcell−1/451 Wh Lcell−1).

Cloud-edge healthcare systems aim to provide low-latency services to both doctors and patients by leveraging storage and computing capabilities located on hospital servers. However, these servers often need to be more trusted and possess limited computing resources, raising concerns regarding data integrity verification. In this paper, we introduce a blockchain-based solution to tackle this challenge. Our approach involves the development of a distributed data integrity verification method that eliminates the need for a third-party auditor. Data is segmented into smaller chunks and hashed to create a hash table, from which verification tags are generated using column-based techniques and a secret string derived from a pseudo-random function. Furthermore, we present a comprehensive blockchain-based data integrity auditing system, which includes mechanisms for verifying the frequency of verification and defining the structure of blocks. Additionally, we conduct a thorough security analysis to assess the resilience of our system against common attacks. Finally, we evaluate the effectiveness of our proposed system against two leading schemes in a simulated cloud-edge healthcare environment. Our results confirm that our system can ensure data integrity without compromising efficiency. [ABSTRACT FROM AUTHOR]

Summary: In contrast to enormous progresses in electrode active materials, little attention has been paid to electrode sheets despite their crucial influence on practical battery performances. Here, as a facile strategy to address this issue, we demonstrate nanofibrous conductive electrode binders based on deoxyribonucleic acid (DNA)-wrapped single-walled carbon nanotubes (SWCNT) (denoted as DNA@SWCNT). DNA@SWCNT binder allows the removal of conventional polymeric binders and carbon powder additives in electrodes. As a proof of concept, high-capacity overlithiated layered oxide (OLO) is chosen as a model electrode active material. Driven by nanofibrous structure and DNA-mediated chemical functionalities, the DNA@SWCNT binder enables improvements in the redox reaction kinetics, adhesion with metallic foil current collectors, and chelation of heavy metal ions dissolved from OLO. The resulting OLO cathode exhibits a fast charging capability (relative capacity ratio after 15 min [versus 10 h] of charging = 83%), long cyclability (capacity retention = 98% after 700 cycles), and thermal stability.

Summary: Coupling thin Li metal anodes with high-capacity/high-voltage cathodes such as LiNi0.8Co0.1Mn0.1O2 (NCM811) is a promising way to increase lithium battery energy density. Yet, the realization of high-performance full cells remains a formidable challenge. Here, we demonstrate a new class of highly coordinated, nonflammable carbonate electrolytes based on lithium bis(fluorosulfonyl)imide (LiFSI) in propylene carbonate/fluoroethylene carbonate mixtures. Utilizing an optimal salt concentration (4 M LiFSI) of the electrolyte results in a unique coordination structure of Li+-FSI−-solvent cluster, which is critical for enabling the formation of stable interfaces on both the thin Li metal anode and high-voltage NCM811 cathode. Under highly demanding cell configuration and operating conditions (Li metal anode = 35 μm, areal capacity/charge voltage of NCM811 cathode = 4.8 mAh cm−2/4.6 V, and anode excess capacity [relative to the cathode] = 0.83), the Li metal-based full cell provides exceptional electrochemical performance (energy densities = 679 Wh kgcell−1/1,024 Wh Lcell−1) coupled with nonflammability. : Electrochemical Energy Storage; Electrochemical Materials Science; Electrochemical Energy Engineering Subject Areas: Electrochemical Energy Storage, Electrochemical Materials Science, Electrochemical Energy Engineering

Antimicrobial resistance has become a major problem in public health and clinical environments. Against this background, antibiotic susceptibility testing (AST) has become necessary to cure diseases in an appropriate and timely manner as it indicates the necessary concentration of antibiotics. Recently, microfluidic based rapid AST methods using microscopic analysis have been shown to reduce the time needed for the determination of the proper antibiotics. However, owing to the inoculum effect, the accurate measurement of the minimal inhibitory concentration (MIC) is difficult. We tested four standard bacteria: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Enterococcus faecalis, against five different antibiotics: piperacillin, cefotaxime, amikacin, levofloxacin, and ampicillin. The results showed that overall, the microfluidic system has a similar inoculum effect compared to the conventional AST method. However, due to the different testing conditions and determination protocols of the growth of the microfluidic based rapid AST, a few results are not identical to the conventional methods using optical density. This result suggests that microfluidic based rapid AST methods require further research on the inoculum effect for practical use in hospitals and can then be used for effective antibiotic prescriptions.