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With advantages such as high theoretical capacity, low cost, and nontoxicity, Zn metal has been widely investigated as an anode for aqueous batteries. However, the problems of dendrite formation and sustained corrosion originating from severe interfacial side reactions and uncontrolled Zn electrodeposition in aqueous electrolytes significantly slows down the practical application of Zn metal anodes. To address these issues, herein, an anti‐corrosion elastic constraint (AEC) is introduced that is built with nanosized TiO2 and polyvinylidene fluoride (PVDF) matrix to Zn anode, where the PVDF layer serves as an elastic H2O/O2‐blocking layer and the decorated TiO2 nanoparticles assist uniform Zn electrodeposition. With this corrosion‐inhibition and electrodeposition‐redirection coating, the electrodeposition consistency and thermodynamic stability of the Zn anode are significantly improved, enabling a long‐term stable plating/stripping performance for 2000 h with an ultralow overpotential (<50 mV) and a high average Coulombic efficiency (>99.4%) for 1000 cycles without obvious dendrite formation. Even at a high current density of 8.85 mA cm−2 with limited Zn supply (DODZn = 60%), stable Zn deposition is achieved over 250 h. When coupled with a MnO2 cathode, the AEC‐Zn anode shows a remarkably enhanced full‐cell cycling stability, indicative of high reliability of aqueous Zn batteries for practical application. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • MnO-carbon hybrid nano-fibers are fabricated via an electrospinning method. • Sintering temperature has an important influence on the performance of the obtained composites. • Material synthesized under optimum temperature can exhibit ideal fiber appearance with MnO particles embedded into it. • Formation mechanism of the materials are also analyzed. Abstract In this paper, MnO-carbon hybrid nanofibers are fabricated via an electrospinning method, while polyvinyl alcohol (PVA) and manganese acetylacetonate are used as raw materials. Composition, phase structure, and morphology of the products obtained under different sintering temperatures are studied with modern analytical instruments, and the electrochemical properties of the MnO/C fibers used as the lithium ion battery anode are also studied by continuous charge/discharge procedures. The results demonstrate that sintering temperature has an important influence on the performance of the obtained composites, and there is an optimum value for synthesizing MnO/C composites. Material synthesized under 600 °C can exhibit an ideal fiber appearance with MnO particles embedded into the material and deliver the highest capacity among all samples. The formation mechanism of the materials is also analyzed in detail in this paper. [ABSTRACT FROM AUTHOR]

In order to improve the electrochemical properties of nano Si-carbon composites, a binder-free Si-CNTs composite with good dispersion of Si nanoparticles were prepared by ionic liquids self-assembly method. [Display omitted] • A binder-free Si-CNTs composites were prepared by ILs assisted self-assembly method. • The as-prepared Si-CNTs composites show ball-like structure, and the SiNPs are dispersed in the carbon nanotubes self-assembly uniformly. • The carbon nanotubes could be self-assembled into a 3D structure through electrostatic gravitational force of ILs, and the heteroatoms of ILs could dope in the carbon skeleton during annealing. • ILs plays an important role in the dispersion of SiNPs in Si-CNTs system. • Si30%-CNTs exhibit excellent cycle performance and rate capability. Binder-free nano silicon/carbon nanotube composites anodes were synthesized by electrostatic self-assembly of ionic liquids (ILs) and annealing process. The addition of [Emim]Tf 2 N ILs successfully improved the dispersion of silicon nanoparticles (SiNPs) in the carbon nanotubes (CNTs). And the carbon nanotubes could be self-assembled into a 3D structure network through electrostatic gravitational force. Moreover, the wettability of electrode also be improved due to the heteroatoms of [Emim]Tf 2 N ILs doped in the CNTs during annealing. By integrating these advantages, the Si30%-CNTs anodes exhibit a high initial reversible discharge capacity of 2580.3 mAh g−1 at a current density of 0.4 A g−1. Even at a much higher current density of 10 A g−1, the Si30%-CNTs anodes can still deliver a high reversible discharge capacity of 871.1 mAh g−1. The outstanding performances compared to traditional coating method are assigned to that the ionic liquids self-assembly method improves the dispersion of SiNPs. [ABSTRACT FROM AUTHOR]

Despite its merits of high specific capacity and intrinsic safety for aqueous zinc‐ion batteries (AZIBs), Zn metal as anode suffers from dendritic growth and severe corrosion during battery operation. Here, an electrolyte surfactant of succinimide (SI) that occupies the compact region of the electrical double layer (EDL) at the Zn/electrolyte interface, which protects the Zn surface from the parasitic corrosion in aqueous electrolytes is reported. More importantly, both theoretical calculation and electrochemical analysis demonstrate that the occupation of SI at the EDL can restrict the self‐diffusion of Zn adatoms and tune interfacial reaction kinetics during Zn deposition, thereby promoting small and dense nuclei rather than large Zn dendrites. Accordingly, SI surfactants enable a high Coulombic efficiency of 99.95% and a long cumulative plated capacity over 6800 mAh cm−2 at 20 mA cm−2 for 10 mAh cm−2. Moreover, the feasibility of SI is also demonstrated on a long‐term cycling stability in Zn‐VS2 batteries. [ABSTRACT FROM AUTHOR]

A new structured Mn 3 O 4 @C composite is fabricated with carbon filled in the pores and coated on the surface of the porous Mn 3 O 4 . This anode material exhibits superior electrochemical properties including high initial coulombic efficiency, outstanding rate properties and cycle performance. The initial coulombic efficiency of this composite approach to 69.5%, and it delivers a capacity of nearly 420 mAh g −1 even at a discharge current of 1800 mA g −1 . The outperforming results could be ascribed to the unique structure of the composite, which can provide meaningful guidance to the design of further anode materials. [ABSTRACT FROM AUTHOR]

Electrochemical performance of the 18650 lithium-ion batteries consisting lithium-rich layered oxides 0.5Li 2 MnO 3 ·0.5LiMn 0.33 Ni 0.33 Co 0.33 O 2 cathode material and soft carbon anode is investigated in detail. The cathode is synthesized by a spray drying process and the properties are studied by various methods, while the soft carbon is commercial available. The assembled batteries can exhibit excellent cyclic performance with a capacity retention of 90.2% even after 600 cycles in the voltage ranges of 2.0-4.5 V (at 1C-rate). Moreover, they can also deliver excellent rate capabilities as the discharge capacity under 40C is nearly equal to 83.9% of that under 1C (voltage range is in 2.0-4.5 V). Furthermore, in order to evaluate the mechanism of the superior performance exhibited by the full cells, cells after 300 cycles are disassembled in a glove box to assess the changes on the active materials by using a series of technique methods, including a scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS), High-resolution transmission electron microscope (TEM) and selected area electron diffraction (SAED). [ABSTRACT FROM AUTHOR]

A novel porous structure MnO-SiO x @C composite has been designed and prepared as an anode material for lithium-ion batteries through scalable spray pyrolysis and a subsequent annealing process. XRD, SEM, TEM, Raman, and BET measurements indicate that the MnO-SiO x @C composite displays a spherical mesoporous structure with SiO x particles, embedded in the porous MnO structure combined with carbon coated on the surfaces. The enhanced electrochemical performance can be attributed to the mutual segregation of the heterogeneous oxides of MnO and SiO x during delithiation and the buffer composition region at the origin of uniform carbon layers and abundant nanopores. In addition, the new phase Mn 2 SiO 4 , which is formed in the MnO-SiO x @C composite after 800 ºC, can act as the joint between MnO and SiO x to restrain the strain force originating from the volume change during the charge and discharge process. As a result, the obtained MnO-SiO x @C composite exhibits significantly enhanced electrochemical performance in terms of high Coulombic efficiency, excellent rate capability and good cyclability. • Porous MnO-SiO x @C microspheres was prepared by spray drying method. • MnO-SiO x @C samples show enhanced cycle stability and rate performance. • The Mn 2 SiO 4 phase played key role in improvement the structure stabilities. [ABSTRACT FROM AUTHOR]

Abstract: Using citric acid–nitrate process, La and Cr co-doped A-site deficient SrTiO3 (LSTC) materials were synthesized. The single-phase perovskite structure of LSTC materials can be obtained in airy atmosphere when the dopant content of chromium does not exceed 20mol%. The LSTC material has excellent chemical compatibility with yttria-stabilized zirconia (YSZ) at 1400°C. The particle diameters of LSTC powders calcined at 800°C are all less than 60nm. The LSTC pellet sintered in air at 1400°C for 5h shows a highly densified microstructure composed of polyhedral grains on a micron scale. At 800°C, the conductivity of LSTC20 pellet is 1.96×10−3 S/cm in static air. The conduction activation energy of LSTC20 pellet is calculated to be 0.33eV in the temperature range of 550–800°C. The LSTC can be considered as a potential candidate anode material for SOFC with YSZ as electrolyte, but its conductivity needs to be further improved. [Copyright &y& Elsevier]

The mechanism underlying the anode graphite's regeneration from the spent lithium-ion batteries is investigated by a semi-in situ X-ray diffraction study combined with electron microscopy and Raman spectroscopy. The impacts of thermal treatment temperatures, durations, and atmospheres (including N 2 , Ar, and He) on the crystal lattice restoration are thoroughly examined to obtain the optimized conditions that impart significant crystal lattice restoration. The N 2 atmosphere can activate the carbon through the reaction of oxygen-containing functionalities with the lithium nitride generated by the reaction between N 2 and the metallic Li precipitated on the anode surface, resulting in the best graphitization effect under the N 2 atmosphere in comparison with the Ar and He. Among all of the investigated calcination temperatures and durations, 3000 °C combined with 6 h is evidenced to be the optimal one for removing the internal stress and achieving the highest degree of graphitization. The regenerated graphite exhibits superior electrochemical properties, with an initial charging capacity of 352.5 mAh·g−1 and capacity retention of 97.3% after 1000 cycles. A pilot-scale test also verifies the effectiveness of the recycling and regeneration method, and the obtained product releases a capacity of 351.9 mAh·g−1 and capacity retention of 87.88% after 1600 cycles. Image 1 • Recycling of graphite wastes from spent lithium-ion batteries (LIBs). • Lattice reconfiguration of anode graphite via carbonization under atmospheres. • Impact of temperatures, durations, and atmospheres on the internal structure. • Mechanistic insights into the graphite regeneration for high-performance LIBs. • Scaled-up regeneration of anode graphite for pilot-scale LIB applications. [ABSTRACT FROM AUTHOR]