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Abstract: Due to high energy density, low cost, and nontoxicity, lithium–sulfur (Li–S) batteries are considered as the most promising candidate to satisfy the requirement from the accelerated development of electric vehicles. However, Li–S batteries are subjected to lithium polysulfides (LiPSs) shuttling due to their high dissolution in liquid electrolyte, resulting in low columbic efficiency and poor cycling performance. Moreover, the Li metal as an indispensable anode of Li–S batteries shows serious safety issues derived from the lithium dendrite formation. The replacement of liquid electrolytes with solid‐state electrolytes (SSEs) has been recognized as a fundamental approach to effectively address above problems. In this review, the progress on applying various classes of SSEs including gel, solid‐state polymer, ceramic, and composite electrolytes to solve the issues of Li–S batteries is summarized. The specific capacity of Li–S batteries is effectively improved due to the suppression of LiPSs shuttling by SSEs, while the rate and cycling performance remain relatively poor owing to the limited ionic conductivity and high interfacial resistance. Designing smart electrode/electrolyte integrated architectures, enabling the high ionic transportation pathway and compatible electrode/electrolyte interface, may be an effective way to achieve high performance solid‐state Li–S batteries. [ABSTRACT FROM AUTHOR]

Abstract: The development of lithium (Li) metal anodes Li metal batteries faces huge challenges such as uncontrolled Li dendrite growth and large volume change during Li plating/stripping, resulting in severe capacity decay and high safety hazards. A 3D porous copper (Cu) current collector as a host for Li deposition can effectively settle these problems. However, constructing a uniform and compact 3D porous Cu structure is still an enormous challenge. Herein, an electrochemical etching method for Cu–Zinc (Zn) alloy is reported to precisely engrave a 3D Cu structure with uniform, smooth, and compact porous network. Such a continuous structure endows 3D Cu excellent mechanical properties and high electrical conductivity. The uniform and smooth pores with a large internal surface area ensures well dispersed current density for homogeneous Li metal deposition and accommodation. A smooth and stable solid electrolyte interphase is formed and meanwhile Li dendrites and dead Li are effectively suppressed. The Li metal anode conceived 3D Cu current collector can stably cycle for 400 h under an Li plating/stripping capacity of 1 mA h cm−2 and a current density of 1 mA cm−2. The Li@3D Cu||LiFePO4 full cells present excellent cycling and rate performances. The electrochemical dealloying is a robust method to construct 3D Cu current collectors for dendrite‐free Li metal anodes. [ABSTRACT FROM AUTHOR]

One dimensional (1D) nanostructures offer prospects for enhancing the electrical, thermal, and mechanical properties of a broad range of functional materials and composites, but their synthesis methods are typically elaborate and expensive. We demonstrate a direct transformation of bulk materials into nanowires under ambient conditions without the use of catalysts or any external stimuli. The nanowires form via minimization of strain energy at the boundary of a chemical reaction front. We show the transformation of multimicrometer-sized particles of aluminum or magnesium alloys into alkoxide nanowires of tunable dimensions, which are converted into oxide nanowires upon heating in air. Fabricated separators based on aluminum oxide nanowires enhanced the safety and rate capabilities of lithium-ion batteries. The reported approach allows ultralow-cost scalable synthesis of 1D materials and membranes. [ABSTRACT FROM AUTHOR]

In order to achieve a high capacity and capacity retention of Ge-based Lithium-ion batteries, it is critical to identify a scalable and economical method to prepare Ge-based materials. We present a mean of preparation and characterization for GeO 2 /SnO 2 (GS) nanofibers produced by electrospinning technique. The optimized GS nanofibers (Ge/Sn mol ratio is 0.88) shows a high initial reversible capacity of 922 mA h g −1 and excellent cyclability (charge capacity retention is 73.9%). [ABSTRACT FROM AUTHOR]

Abstract: Uniform hierarchical SnS2 structures were synthesized by a facile solvothermal approach. Based on time-dependent experiments results, a possible formation mechanism of the hierarchical SnS2 architectures was proposed. Mesoporous hierarchical SnO2 also could be obtained by calcining the corresponding SnS2 structures. When used as the anode materials of rechargeable lithium-ion batteries, both of them showed high specific capacities and enhanced rate capacities. [Copyright &y& Elsevier]

Urchin-like nano/micro-structured FeO/C composite has been successfully synthesized using inexpensive starting materials. The urchin-shaped nano/micro-structure consisted of several oriented nanorods. TEM analysis revealed that there is a large number of pores and uniform amorphous carbon distribution at a nanoscale in the nanorods walls. As used in lithium-ion batteries, the mesoporous FeO/C anode delivered a higher reversible capacity of about 830 mAh g at 0.1 C up to 50 cycles, as well as enhanced high-rate capability compared with urchin-like FeO and commercial FeO. The improvements can be attributed to the combined effects of the nano/micro-architecture, the porosity, and the ultra-fine carbon matrix, where the three factors would contribute to possess both the merits of nanometer-sized building blocks and micro-sized assemblies and provide high electronic conductivity. It is believed that the results of this study offer new prospects for improving the lithium storage capacity of metal oxides by controlling both architecture and composition. [ABSTRACT FROM AUTHOR]

Sodium metal batteries have emerged as potential rivals to lithium‐ion batteries. Nevertheless, maintaining a stable sodium metal anode under harsh conditions (current density >10 mA cm−2) is extremely challenging. The primary issue is the highly reactive sodium metal continuously reacts with the electrolyte to form a thick and loose solid electrolyte film. The tip effect causes sodium ions (Na+) accumulated in the bulge resulting in uneven deposition. In this paper, a unique artificial interfacial layer (Ag nanoparticles distributed in NaClO4‐based matrix) is prepared on the surface of a metallic sodium anode using in situ displacement reaction. Ag particles arranged at the bottom of the artificial layer act as effective nucleation sites helping Na+ deposit uniformly, while the built‐in electric field formed between Ag in the middle/top of the artificial layer and the sodium accelerates the migration of Na+ in the interfacial layer during the deposition and reduce the polarization. Such important properties further allow the steady operation of modified sodium metal batteries in very harsh conditions. The symmetric battery achieves reversible stripping/plating for over 1000 h under high current density (10 mA cm−2). Moreover, the full cell coupled with a high‐loading Na3V2(PO4)3 cathode (20 mg cm−2) presents a stable cycle performance. [ABSTRACT FROM AUTHOR]

Abstract: Ni foam suppported-SnO2 nanorod arrays with controllable diameter were prepared via a template-free growth method, which was a convenient route for the large-scale growth of pure-phase metal oxide nanorod arrays on metal substrates. The relationship between electrochemical behavior and the shape of SnO2 nanorod arrays has been investigated in detail. SnO2 nanorod arrays with diameter of about 25nm, as anode materials for Li-ion batteries revealed a capacity of 607mAh g−1 (at 0.2 C) up to 50 cycles. The superior performance of the SnO2 nanorods can be mainly attributed to small size of nanorods which reduce volume expansion and lithium diffusion length. [Copyright &y& Elsevier]

In article number 1805301, Yan‐Bing He and co‐workers report a low resistance integrated all‐solid‐state Li metal battery with excellent electrochemical performance. The battery structure applies polyethylene oxide with lithium bis(trifluoromethylsulphonyl)imide as both the binder of the cathode and matrix of the composite electrolyte embedded with Li7La3Zr2O12 nanowires. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium metal battery is the most promising next‐generation energy storage device. However, the low ionic conductivity of solid electrolytes and high interfacial impedance with electrode are the main factors to limit the development of all‐solid‐state batteries. In this work, a low resistance–integrated all‐solid‐state battery is designed with excellent electrochemical performance that applies the polyethylene oxide (PEO) with lithium bis(trifluoromethylsulphonyl)imide as both binder of cathode and matrix of composite electrolyte embedded with Li7La3Zr2O12 (LLZO) nanowires (PLLN). The PEO in cathode and PLLN are fused at high temperature to form an integrated all‐solid‐state battery structure, which effectively strengthens the interface compatibility and stability between cathode and PLLN to guarantee high efficient ion transportation during long cycling. The LLZO nanowires uniformly distributed in PLLN can increase the ionic conductivity and mechanical strength of composite electrolyte efficiently, which induces the uniform deposition of lithium metal, thereby suppressing the lithium dendrite growth. The Li symmetric cells using PLLN can stably cycle for 1000 h without short circuit at 60 °C. The integrated LiFePO4/PLLN/Li batteries show excellent cycling stability at both 60 and 45 °C. The study proposed a novel and robust battery structure with outstanding electrochemical properties. A low resistance–integrated all‐solid‐state Li metal battery with excellent electrochemical performance is designed. The structure not only guarantees high ionic conductivity and good mechanical properties to suppress lithium dendrite growth by using polyethylene oxide (PEO)/lithium bis(trifluoromethylsulphonyl)imide embedded with Li7La3Zr2O12 nanowire composite electrolyte, but also decreases the interfacial impedance by applying PEO in both electrolyte and cathode that can fuse during operation. [ABSTRACT FROM AUTHOR]

Composite gel polymer electrolyte (CGPE), derived from ceramic fillers has emerged as one of the most promising candidates to improve the safety and cycling stability of lithium metal batteries. However, the poor interface compatibility between the ceramic phase and polymer phase in CGPE severely deteriorates lithium‐ion pathways and cell performances. In this work, a fluorescent ceramic nanowire network that can palliate the energy barrier of photoinitiators and contribute to preferential nucleation and growth of polymer monomers is developed, thus inducing polymer segment orderly arrangement and tightly combination. A proof‐of‐concept study lies on fabrications of poly(ethylene oxide) closely coating on the ceramic nanowires, thus dividing the matrix into mesh units that contribute to directional lithium‐ion flux and dendrite‐free deposition on the metallic anode. The CGPE, based on the state‐of‐the‐art self‐luminous framework, facilitates high‐performance quasi‐solid‐state Li||LiFePO4 cell, registering a high capacity of 143.3 mAh g−1 after 120 cycles at a mass loading of 12 mg cm−2. X‐ray computed tomography provides an insight into the relationship between directional lithium‐ion diffusion and lithium deposition behavior over the electrochemical processes. The results open a door to improve the electrochemical performances of composite electrolytes in various applications. [ABSTRACT FROM AUTHOR]

Multicomponent composites with an atomic-scale distribution of different component and an integrated lattice structure may manifest an enhanced synergistic effect compared to the mechanical mixture. In this paper, multicomponent Zn 0.12 Co 0.88 CO 3 composite with high tap density (2.11 g cm −3 ) synthesized via one-step solvothermal method, which exhibits hexagonal structure similar to that of the monocomponent cobalt carbonate (CoCO 3 ). The Zn-substitution could significantly improve the charge and discharge capacity of CoCO 3 from 1001.6 mAh g −1 to 1253.7 mAh g −1 at 0.2 C. When the Zn-substituted CoCO 3 is embedded in carbon nanotubes (CNT) network, the rate performance of Zn 0.12 Co 0.88 CO 3 can be improved greatly. The resulting Zn 0.12 Co 0.88 CO 3 /CNT exhibits outstanding rate performance, delivering a reversible capacity of 1098.4, 840.8, and 610.7 mAh g −1 at 0.5, 1 and 2 C, respectively. The excellent performance of Zn 0.12 Co 0.88 CO 3 /CNT is ascribed to the unique micro-sphere structure with carbon nanotubes. The elastic CNT networks are introduced to wrap the Zn 0.12 Co 0.88 CO 3 , which can not only provide a highly conductive network for electron transfer, but also serve as a buffer to alleviate the aggregation and volume changes of Zn 0.12 Co 0.88 CO 3 nanoparticles. The Zn 0.12 Co 0.88 CO 3 /CNT composite may serve as a novel high-capacity LIBs anode material for practical application, and a facile strategic approach is introduced for the full-molar-ratio synthesis of multicomponent composites. [ABSTRACT FROM AUTHOR]

Abstract: Lithium–metal fluoride batteries promise significantly higher energy density than the state‐of‐the‐art lithium‐ion batteries and lithium–sulfur batteries. Unfortunately, commercialization of metal fluoride cathodes is prevented by their high resistance, irreversible structural change, and rapid degradation. In this study, a substantial boost in metal fluoride (MF) cathode stability by designing nanostructure with two layers of protective shells—one deposited ex situ and the other in situ is demonstrated. Such methodology achieves over 90% capacity retention after 300 charge–discharge cycles, producing the first report on FeF3 as a cathode material, where a very high capacity utilization in combination with excellent stability is approaching the level needed for practical applications of FeF3. The cathode solid electrolyte interphase (CEI) containing lithium oxalate and BF bond containing anions is found to effectively protect the cathode material from direct contact with electrolytes, thus greatly suppressing the dissolution of Fe. Quantum chemistry and molecular dynamics calculations provide unique insights into the mechanisms of CEI layer formation. As a result, this work not only demonstrates unprecedented performance, but also provides the reader with a better fundamental understanding of electrochemical behavior of MF cathodes and the positive impact observed with the application of a lithium bis(oxalato)borate salt in the electrolyte. [ABSTRACT FROM AUTHOR]

Abstract: Stable binder network of anode is essential for the enhanced cycling performance of lithium ion battery electrode especially for SnO2 anode, which has a big volume expansion/shrink during cycling. Here, we designed a cross‐linked polymer adhesive networks for SnO2 anode of sodium‐ion battery by utilizing esterification reaction of PAA (Polyacrylic acid) and SS (soluble starch). The cross‐linked adhesive networks can effectively enhance the contact between conductive agent and SnO2 particles, meanwhile serve as a buffer matrix of the expansion of SnO2 during cycling and a protecting layer to reduce the contact of SnO2 anode and electrolyte. As a result, a stable specific capacity of 370 mA h g−1 of the PAA‐SS@SnO2 anode was obtained at a current density of 0.1 A g−1 after 150 cycles, while the specific capacity of PVDF@SnO2 anode is only 200 mA h g−1 after 50 cycles. This cross‐linked adhesive networks present an effective and universal approach for application of pure SnO2 as high performance anode of sodium ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we constructed 3D flower-like MoS2 spheres with nanosheets (less than 10nm) by a simple alcohol-assisted solvothermal route. It was found that the presence of alcohol enhanced the dispersity of MoS2 samples, and the distilled water facilitated the formation of nanosheets through varying the volume ratio of alcohol and distilled water. The prepared MoS2 samples delivered high initial discharge capacity (1346mAhg−1 at a current density of 100mAg−1), good coulombic efficiency (77.49% retention for the first cycle and ∼100% for the subsequent cycles), excellent cycling performance (947mAhg−1 at 100mAg−1 after 50 cycles) and remarkable rate behavior as anode materials for lithium ion batteries. The superior behavior of MoS2 samples for lithium ion batteries can be ascribed to the thin nanosheets, high specific surface area and their unique layered structure. [Copyright &y& Elsevier]

Abstract: 3D flower-like NiO hierarchical architectures have been synthesized by a simple ethanolamine (EA)-mediated self-assembly route and subsequent calcination process. The synthesized β-Ni(OH)2 precursors annealed at 300, 400 and 500°C exhibit similar morphology by scanning electron microscopy and different crystallinity, surface area, and pore distribution via X-ray diffraction, Fourier transform infrared spectroscopy and nitrogen adsorption/desorption isotherms. The electrochemical properties indicate that the synthesized NiO hierarchical architectures annealed at 300°C show the best electrochemical performance, which presents a reversible specific capacity of 713mAhg−1 at a current density of 100mAg−1 after 40 cycles. With varying the rate from 100 to 1000mAg−1, the capacity still remains 580mAhg−1 at 500mAg−1 after 18 cycles and resumes to 470mAhg−1 at the same rate after 30 cycles. The above results indicate that the 3D flower-like NiO hierarchical architectures are promising anode materials for lithium ion batteries. [Copyright &y& Elsevier]

Abstract: In this work, three-dimensional mesoporous NiO nanostructures have been synthesized by a simple ethylene glycol (EG)-mediated self-assembly route and subsequent calcination process. The synthesized nickel alkoxide precursors annealed at 300 and 500°C exhibit different surface area, crystallinity and pore distribution, which have been characterized by scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, X-ray diffraction, Fourier transform infrared spectroscopy and Nitrogen adsorption/desorption isotherms. The electrochemical properties of these NiO mesoporous nanostructures are investigated including the cycling and rate performance as anode materials for lithium-ion batteries. It is indicated that mesoporous NiO nanospheres synthesized at 500°C exhibit better electrochemical performance than that obtained at 300°C. The NiO nanospheres annealed at 500°C present a reversible specific capacity of 518mAhg−1 at a current density of 0.1Ag−1 after 60 cycles. With varying the rate from 0.1 to 8.0Ag−1, the capacity remains at 535mAhg−1 at 2Ag−1 after 30 cycles and resumes to 582mAhg−1 at 0.1Ag−1 after 60 cycles. The results indicate that our mesoporous NiO nanospheres are promising anode materials for lithium ion batteries. [Copyright &y& Elsevier]