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The continuous parasitic reactions (i.e. , corrosion) between lithium (Li) and electrolyte gradually exhaust Li supply, leaving batteries of longevity great challenges. Li corrosion relates to Li deposition morphology and characteristics of solid-electrolyte interphase (SEI). Here, we quantitatively detect the Li corrosion, and structural and chemical features of SEI in typical ether and ester electrolytes with varied concentrations. SEI dissolution exposes Li to electrolyte, and initiates chemical/electrochemical corrosion. Concentrated ether electrolytes designed as anti-corrosion solution promises dense Li deposits and formation of fluorinated-SEI (30 nm), which reduces the exposure of Li, and suppresses both the chemical and electrochemical corrosion. Li corrosion is declined by 52% (0.53 versus 1.10 μAh h−1). Therefore, both Li||Li (>4950 hours) and LiFePO 4 ||Li cells (750 cycles) can be stably cycled with greatly extended lifespans. This work reveals the battery failure from perspectives of corrosion science, and provides solutions to batteries with longevity by interdicting corrosion. [Display omitted] • The relationship among Li corrosion, Li deposition morphology and SEI characteristics in electrolytes has been detected. • The concentrated ether electrolyte design reduces Li corrosion by 52% (0.53 μAh h−1 vs. 1.10 μAh h−1). • The dense Li deposition and fluoride-SEI layer (30 nm) design enables stable cycling of the Li||Li cell for 4950 hours. • The electrolyte design from the corrosion science helps to supplement additional solution for battery failure. [ABSTRACT FROM AUTHOR]

Room-temperature sodium-sulfur batteries have attracted extensive attention as a cost-effective and high theoretical energy density next-generation energy storage systems. However, the insulating nature of sulfur, the sluggish reactivity of sulfur with sodium, and severe dissolution of polysulfide are the main challenges of this technology. Here, we propose a covalent sulfur bond breakage mechanism by bonding of sulfur chain onto the inner cavity of the sulfydryl-functionalized mesoporous hollow carbon spheres (MHCS) to efficiently promote the generation of short-chain sodium polysulfide and accelerate polysulfide redox kinetics. The covalent sulfur confined MHCS (S@MHCS) cathode delivers an unprecedented rate capability (250 mAh g−1 at 5 C) and exhibits excellent long-term cycling stability over 1000 cycles at 1 C with a high cathode loading of 5 mg cm−2. Moreover, the associated electrochemical reaction mechanism is also revealed by ex-situ X-ray photoelectron spectroscopy and theoretical calculation. This work introduces a novel sulfur cathode design to enhance the performance of room-temperature sodium-sulfur batteries. [Display omitted] • Systematically study the pore structure-performance relationship and the associated electrochemical reaction mechanism. • S@MHCS cathode achieves unprecedented rate capability and exhibits good long-cycling stability. • This work proposes a novel covalent sulfur bond breakage mechanism to develop RT Na-S batteries. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal has been regarded as promising candidate anode to upgrade the energy density of Li secondary batteries. However, uncontrollable formation of Li dendrite, serious volumetric change, undesirable side reaction and poor mechanical properties of solid electrolyte interphase (SEI) layer impede the commercialization of this technology. By ex-situ observing the initial Li deposition process and conducting electrochemical test, we firstly confirm the prior nucleation behavior of Li metal at the step edge area. We thus employ a balsa wood derived porous carbon matrix as Li host and metal oxide nanoparticles are introduced to increase the nanoscale step amounts for Li nucleation. Hence, the Li nucleation overpotential is reduced and Li can be well accommodated within carbon matrix. Moreover, this step-edge-guided effect could promise the Li striping/plating to happen mainly around the steps area within channels, achieving a dendrite-free anode. Consequently, the modified Li anode is capable of working under an ultrahigh current density of 15 mA cm −2 with a Coulombic efficiency of ~ 96% and exhibit lower nucleation overpotential, more satisfactory cycling stability. And when in pair with commercial LiCoO 2 cathode, it shows better rate performance and higher capacity compared with bare Li foil. [ABSTRACT FROM AUTHOR]

Lithium metal as an attractive anode material has been widely used in the advanced energy storage technology such as lithium-sulfur and lithium-air batteries. However, suffering from the uncontrollable deposition, growth of lithium dendrite and the serious volume change within cycling process, the commercial application of lithium anode is impeded by the safety hazards and limited span-life. Here, we demonstrate a kind of bamboo-derived 3D hierarchical porous carbon decorated by ZnO quantum dots which can serve as a lithiophilic scaffold for dendrite-free Li metal anode. This carbon scaffold is stable against the serious volumetric change during cycles. In addition, the 3D porous scaffold can reduce the effective local current density. Most importantly, the lithiophilic ZnO quantum dots within the carbon can be used to induce lithium deposition. Notably, lithium metal up to 131 mAh cm −2 can be confined within ZnO@HPC, achieving acceptable volume expansion, considerable reduction in overpotential and effective dendrite suppression. Thus, 3D Li within ZnO@HPC scaffold could exhibit better capability and much lower voltage hysteresis when compared with Li foil in cells paired with LiCoO 2 . The function of the ZnO decorated 3D hierarchical porous carbon scaffold might provide innovative insights into the design principles for metallic lithium anodes. [ABSTRACT FROM AUTHOR]

In this work, porous MnO/C composites were successfully synthesized via a new ammonia diffusion method, in which the MnO nanoparticles were tightly embedded into a porous carbon matrix. Kapok fibers (KFs) were used as both the bio-template and the renewable carbon source. The KFs-templated MnO/C electrodes exhibited a high reversible specific capacity of 1454 mAh g −1 with a high coulombic efficiency, up to 98%, at a current density of 200 mA g −1 over 150 cycles. The high reversible capacity of the MnO/C composites could be ascribed to the synergetic effects of several factors including the unique porous microstructure, the small MnO nanoparticle size and the high defective carbon matrix. Due to the small MnO nanoparticles size and a moderate amount of carbon (13.3 wt%), the electrodes showed a small voltage polarization (about 0.89 V). [ABSTRACT FROM AUTHOR]

The additive manufacturing of structures and devices in nanoscale yields the possibility of extending the functionalities of nanoelectronics and developing the alternative nanofabrication technologies for the post-silicon era. The nanorobotic spot-welding that is implemented by the transporting of mass inter/intra through the carbon nanotube has been demonstrated in previous works. However, the continuous feeding of the metal mass in nanoscale, as well as the servo control of such mass feeding rate and 3D path of the nanotube injector is still unsolved. In this report, we demonstrated a nanotube fountain pen (NFP). It is equipped with a metal-filled carbon nanotube (m@CNT) as a pen-tip injector to “write” and a nanotube network as an “ink reservoir”. In this way, it is able to provide the possibility of fabricating 3D nanostructures in a continuous fashion. The resolution of NFP depending on the diameter of the nanotube-injector and the mass flow rate of it can be modulated by external electrical driven energy. The development and control of NFP provide a new additive manufacturing technique in nanoscale, and thereby enables potential to develop a NFP-based metallic 3D nanoprinting system for the large-scale, high-throughput manufacturing of nanodevices. [ABSTRACT FROM AUTHOR]

Abstract: A high-yield of carbon nanotubes filled with β-Sn nanowires has been produced by the thermal pyrolysis of acetylene over SnO2 catalysts. Electron beam irradiation (EBI) induced melting and flow of Sn in the nanotubes and this could be controlled by changing the electron beam current density. The mass flow rate of the Sn ranged from 0.9 to 8.2fg/s. The melting of the nanowires is a result of the temperature rise caused by the EBI. Many factors, including temperature variation, charging, and EBI induced deformation of the carbon shells, contribute to the flow of Sn. [Copyright &y& Elsevier]

Sodium (Na)-ion batteries (SIBs) have recently received much attention from the battery community because of their high compatibility with large-scale electrochemical energy storage requiring sufficient energy density, high power capability and low material cost. As such, considerable efforts have been devoted to the search for suitable Na storage materials with superior electrochemical properties. Phosphides are regarded as promising candidates for SIB anodes owing to their high theoretical capacities and low working voltage but, regrettably, suffer from large volume expansion upon Na insertion/extraction and associated inferior interfacial stability. Recent developments in the studies of phosphides have trended toward morphological designs and interfacial modifications, which have realized significant improvements in specific capacity, rate capability and cycling lifespans. Based on these fruitful achievements, it is timely to review the recent progress of phosphides in SIB anodes. Different species of phosphides are classified into three sections to be discussed. We also focus on the correlation between the nanostructure and electrochemical performance. Meanwhile, interfacial analysis of phosphide anodes is intensively given. Finally, we conclude by providing an overview of future challenges and opportunities based on using phosphides for SIB anodes. Schematic of the modification strategies for high performance SIBs. [Display omitted] • The progress of phosphides for sodium ion battery anode is comprehensively reviewed. • The reaction mechanism in charge/discharge processes to explain the origin of volume expansion is specifically analyzed. • Current challenges and future perspective for improving electrochemical performance of phosphides are proposed. [ABSTRACT FROM AUTHOR]

The ultrahigh-energy-density lithium (Li) metal anodes have received increasing attentions for developing next-generation Li batteries, nevertheless, the safety concern and interior cycling stability originated from the intrinsically dendritic Li plating, have greatly hinder their further applications. Herein, three-dimensional networks assembled form the mineral xonotlite (Ca 6 Si 6 O 17 (OH) 2) nanowires (XNs) with high specific surface area, strong electrolyte affinity and flame-retardant property are designed to homogenize the Li+ flux and alleviate the dendrite-caused safety hazards. Moreover, this lithiophilic scaffold promises a homogeneous Li nucleation. Particularly, a small percentage of XNs reacts into Li x SiO y which accumulates in the solid electrolyte interphase (SEI) as cycling. Aided by the atomic visualization from cryo-transmission electron microscopy, the monoclinic phase of crystalline Li 4 SiO 4 in SEI is identified, which exhibits a Li+ conduction 1000 times higher than that of Li 2 O according to the molecular dynamic simulation. Hence, the regulated SEI with excellent Li+ transfer capability reduces the preferential growth of high-energy Li facets, thus realizing dendrite-free Li deposition. When paired with unstable LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM 811) cathode, the full cells of Li-XNs-NCM 811 show a capacity retention of 88% after ultralong 1600 h. This strategy would provide inspirations on rational design towards high-safety long-cycling Li metal batteries. Xonotlite nanowires (XNs) were synthesized with homogeneous porosities, lithiophilic and flame-retardant properties for uniform Li nucleating and plating. Partial XNs reacted to the ultrahigh-ion-conductive Li 4 SiO 4 , as identified by cryo-transmission electron microscopy, and participated in solid electrolyte interphase as cycling. The silicious SEI with enhanced Li+ transfer enabled bulk Li growth, thus realizing dendrite-free Li metal battery with extraordinary cyclic stability and safety. [Display omitted] • Lithiophilic and flame-retardant xonotlite nanowires (XNs) are designed for dendrite-free high-safety Li metal batteries. • Cryo-TEM and simulation identify the crystalline Li4SiO4 with excellent Li+ transfer capability in the XNs generated SEI. • The full cells integrated of Li-XNs- LiNi0.8Co0.1Mn0.1O2 exhibit a high capacity retention of 88 % after 1600 h cycling. [ABSTRACT FROM AUTHOR]

A brief timeline summarizing the development of these strategies in hosts, artificial protection layer, and electrolyte additives. [Display omitted] Using lithium (Li) directly as metal anode for a higher energy density battery is one of the most attractive battery researches in the past decade. To address its intrinsic issues including uncontrolled growth of Li dendrites and unstable solid electrolyte interphase (SEI), which are believed as the main origins of safety issues and short lifetime, proposing the groundbreaking concepts and contributing valuable improvements in the development of Li metal anodes (LMAs) have always been the mandate of all battery scientists. This review presents a historical framework of various concepts and contributions in enabling LMAs to be applied practically. We begin with an overview of these important concepts and breakthroughs in different aspects to advance LMAs. Moreover, assisted by the big data sources from Web of Science, the major contributions from institutions, journals, corresponding authors, and highly cited papers are discussed and summarized. Finally, future trends and challenges are concluded for designing an ideal LMA. We hope that such as a comprehensive evolutionary story of LMAs can motivate more researchers to pave the way for high-energy lithium metal batteries (LMBs) in the future. [ABSTRACT FROM AUTHOR]

Abstract: Spherical LiFePO4/C powders were synthesized by the conventional solid-state reaction method via Ni doping. Low-cost asphalt was used as both the reduction agent and the carbon source. An Ni-doped spherical LiFePO4/C composite exhibited better electrochemical performances compared to an un-doped one. It presented an initial discharge capacity of 161mAhg−1 at 0.1C rate (the theoretical capacity of LiFePO4 with 5wt% carbon is about 161mAhg−1). After 50 cycles at 0.5C rate, its capacity remained 137mAhg−1 (100% of the initial capacity) compared to 115mAhg−1 (92% of the initial capacity) for an un-doped one. The electrochemical impedance spectroscopy analysis and cyclic voltammograms results revealed that Ni doping could decrease the resistance of LiFePO4/C composite electrode drastically and improve its reversibility. [ABSTRACT FROM AUTHOR]

Abstract: LiFePO4/C composite cathode materials with carbon nano-interconnect structures were synthesized by one-step solid state reaction using low-cost asphalt as both carbon source and reducing agent. Based on the thermogravimetry, differential scanning calorimetry, transmission electron microscopy and high-resolution transmission electron microscopy, a growth model was proposed to illustrate the formation of the carbon nano-interconnect between the LiFePO4 grains. The LiFePO4/C composite shows enhanced discharge capacity (150mAhg−1) with excellent capacity retention compared with the bare LiFePO4 (41mAhg−1) due to the electronically conductive nanoscale networking provided by the asphalt-based carbon. The results prove that the asphalt is a perfect carbon source and reduction agent for cost-effective production of high performance LiFePO4/C composite. [Copyright &y& Elsevier]

A facile, efficient, environmentally benign route has been reported to synthesize toast-like porous carbon (TPC) materials via one-step solid reaction between LiH and CaCO 3 powder mixture at 600 °C. The release of gas from the reaction process plays a key role in the formation of toast-like micro-/meso-porous structure. As an anode material for Li ion batteries, the as-synthesized TPC exhibits ultrahigh specific capacity of 1016 mAh g −1 (after 300 cycles at 200 mA g −1 ), superior rate capability (730 mAh g −1  at 1000 mA g −1 ), and excellent cycling stability up to 1400 cycles at 4000 mA g −1 . The exceptional lithium storage performance of TPC could be attributed to its novel hierarchical structure, which not only provide high accessible surface area for charge storage, but also act as reservoirs for lithium storage. This chemical reaction route opens new avenues for synthesizing porous carbon materials for energy storage application. [ABSTRACT FROM AUTHOR]

Kapok fibres were used as micro-tube biotemplate and bio-carbon source to synthesise Fe 3 O 4 /C composites, which were then utilised as anode materials. Fe 3 O 4 nanoparticles were grown uniformly onto the external surface and internal channel of kapok carbon fibres. The flexibility, high specific surface area and electronic conduction of kapok fibres can buffer the volume expansion as well as inhibit the aggregation of Fe 3 O 4 nanoparticles. Thus, the electrical integrity and structural of the Fe 3 O 4 /C composites electrode during lithiation/delithiation processes. The Fe 3 O 4 /C composites electrode delivers a high reversible capacity of 596 mA h g −1 after 100 cycles and an ultra-high coulombic efficiency approaching 100%. The high electrochemical performance of the Fe 3 O 4 /C composites can be caused by the synergistic effect of the Fe 3 O 4 nanoparticles and the structure of kapok carbon fibres. [ABSTRACT FROM AUTHOR]

A novel hybrid nanoarchitecture of TiO 2 nanotubes/graphene was synthetized through a facile two-step hydrothermal route. The anatase TiO 2 nanotubes with a diameter of about 20 nm show a net-like structure and high dispersion on the graphene nanosheets. The as-prepared sample (TOG2) exhibits a high average capacity of 410 mAh g −1 at 0.1 A g −1 , superior cycling stability with negligible capacity fade over 300 cycles and rate capability of 192 mAh g −1 at 1 A g −1 . The enhanced electrochemical properties can be attributed to its unique hybrid structure. One-dimensional hollow tubular structure of TiO 2 provides numerous open channels for electrolyte to access and facilitate the ultrafast diffusion of lithium ions. In addition, the graphene sheets are favorable for the fast electron transport within the electrode, as well as keep the structural integrity during long-term cycling processes. [ABSTRACT FROM AUTHOR]

Submicron silica (SiO 2 ) is prepared via directly milling bulk SiO 2 , which is the major constituent of the abundant sand on the earth. The electrochemical lithium storage performance of SiO 2 is found to be strongly associated with the ball milling treatment. The reversible capacity of SiO 2 gradually increases from 163 to 803 mAh g −1 as the milling time is extended from 0 to 72 h. For the SiO 2 milled for 24 h, it exhibits excellent cycling performance with a discharge capacity of 602 mAh g −1 over 150 cycles, corresponding to the capacity retention of 99.8% relative to the 2nd cycle. The different particle sizes distribution and electrochemical activity of SiO 2 are responsible for the effect of ball milling on its electrochemical lithium storage performance such as reversible capacity, cycling stability, electrode polarization and initial Coulombic efficiency. [ABSTRACT FROM AUTHOR]