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• Li 3 P protective layer induces uniform deposition of Li+ ions. • Li 3 P protective layer homogenizes the charge distribution on the electrode. • Li 3 P protective layer observably reduces side reactions with the electrolyte. • Li 3 P@Li electrode exhibits excellent capacity retention rate and cycling stability. To suppress dendrites and avoid side reactions that hinder the practical application of Li metal anode, a homogeneous lithiophilic Li 3 P layer is cast on the Li metal anode surface (Li 3 P@Li) via a simple impregnation process. The low Li+ diffusion barrier of the obtained Li 3 P layer facilitates the dendrite-free Li deposition. A prolonged cycle life of 2740 h with low overpotential (∼10 mV) is thus achieved by the Li 3 P@Li electrode. The cycle performance of Li 3 P@Li || LiFePO 4 full cell is also improved, which remains an 85 % capacity retention after 1200 cycles at 3C. This work provides new ideas for Li metal anode surface engineering and promotes Li metal anode's practical application. [Display omitted] [ABSTRACT FROM AUTHOR]

ZnSe is considered to be an intriguing anode material arising from its high theoretical capacity and low cost in potassium ion batteries (PIBs). The poor reaction kinetics and unfavorable structural stability, however, largely impede the performance. Herein, a dual carbon manipulated yolk-shell ZnSe microsphere (ZnSe-C@NC) is rationally envisaged, with ideal construction stability and efficient K+ diffusion process. A high discharge capacity of 549.9 mAh g−1 with favorable initial Coulombic efficiency of 81.8% can be achieved at 100 mA g−1. Even at the current density of 1000 mA g−1, the reversible capacity is as high as 456.4 mAh g−1. Concurrently, a full PIB based on ZnSe-C@NC is designed with a high energy density of 133.8 Wh kg−1 at the power density of 236 W kg−1. The experiment and in-depth density functional theory (DFT) calculation results demonstrate that the N doped carbon decoration on ZnSe would greatly accelerate charge transportation, narrow the bandgap and minimize K+ movement energy barrier. On the other hand, the dual carbon protection endow that the unique yolk-shell construction with superb mechanical stability during long circulation, bringing about exceptional electrochemical performance. [Display omitted] [ABSTRACT FROM AUTHOR]

• Carbon encapsulated MnMoO 4 microrods are realized in this work. • The MnMoO 4 @C microrods show excellent performance in SIBs and PIBs. • A sodium ion capacitor (SIC) based on MnMoO 4 and Na 3 V 2 (PO 4) 3 is employed. • The SICs display energy densities of 168 and 88 Wh kg−1 at 240 and 4000 W kg−1. Mixed transition metal molybdate oxides (AMoO 4 where A = Ni, Co, Fe, Mn) manifest high capacities (≈ 980 mAh g −1) via the multiple redox reactions, with the Mo ranging from Mo6+ to Mo0. What's more, this dual metal oxides exhibit superior performance to single transition metal oxide, as a result of the synergic effects of multiple transition metals and the better electrical conductivity than that of single metal oxide. Bimetallic MnMoO 4 shows satisfied performance in lithium ion batteries (LIBs), but its performance in sodium ion batteries (SIBs) and potassium ion batteries (PIBs) has not been exploited. On account of this, a carbon encapsulated MnMoO 4 microrod is designed as the anode material in SIBs and PIBs. It is detected that the electrochemical performance of the carbon encapsulated MnMoO 4 microrods in SIBs is highly boosted with respect to the bare MnMoO 4. In view of the pseudocapacitance effect of MnMoO 4 microrods in SIBs, a sodium ion capacitor (SIC) based on MnMoO 4 capacitor-type anode and Na 3 V 2 (PO 4) 3 battery-type cathode is employed and displays high energy densities of 168 and 88 Wh kg−1 at 240 and 4000 W kg−1. [Display omitted] [ABSTRACT FROM AUTHOR]

NiCr 2 O 4 is successfully prepared via hydrothermal pretreatment and subsequent sintering, which shows excellent electrochemical performance as a new anode material for lithium ion batteries with natural graphite adding and sodium alginate binder. At a specific current of 70 mA g −1 , it delivers charge and discharge capacities of 465.5 and 919.8 mAh g −1 in the initial cycle, which gradually increases along with cycle number owing to an electrochemical reconstruction in cycling. After 100 cycles, the charge and discharge capacities are 582.9 and 592.5 mAh g −1 , respectively. Furthermore, it is testified that natural graphite adding can effectively improve the electronic conductivity of the NiCr 2 O 4 electrode, and an appropriate amount of natural graphite is beneficial to improve the specific capacity and cycle stability of the electrode owing to a coordinated electrochemical reconstruction between NiCr 2 O 4 and natural graphite in cycling. [ABSTRACT FROM AUTHOR]

A low cost and facile way was developed to prepare high performance Fe 2 O 3 /natural graphite electrode for lithium ion batteries. For the purpose of reducing the cost and improving the feasibility of large-scale fabrication, commercial ferric oxide and natural graphite were adopted as raw materials and mechanical milling was adopted as preparation method in material fabrication process, and water soluble sodium alginate was adopted as binder in electrode preparation procedure. The Fe 2 O 3 /natural graphite electrode delivers initial discharge and charge capacity of 943.8 and 691.4 mAh g -1 at a specific current of 72 mA g -1 , maintaining of 687.6 and 679.3 mAh g -1 after 100 cycles. After 60 cycles at various specific currents from 104 to 3470 mA g -1 , the discharge and charge capacity of the Fe 2 O 3 /natural graphite electrode can restore well when lowering the specific current to 104 mA g -1 . A novel electrochemical reconstruction between Fe 2 O 3 and natural graphite was observed for the electrode after cycling, which results in the formation of an integrated architecture with good combination between Fe 2 O 3 and natural graphite, being responsible for the good electrochemical performance. [ABSTRACT FROM AUTHOR]

Li 3 VO 4 nanoparticles with mean size about 100 nm are uniformly deposited on the surface of natural graphite via a quasi sol gel method. The electrochemical performance of the Li 3 VO 4 /natural graphite composite as anode for lithium ion batteries is studied via galvanostatic battery testing, which shows excellent cycle stability and rate capability. At a specific current of 156 mA g −1 , it delivers discharge and charge capacity of 579 and 427 mAh g −1 in the initial cycle, which maintain of 469 and 468 mAh g −1 after 100 cycles. After 60 cycles at various specific currents from 234 to 11,719 mA g −1 , the discharge capacity can restore to 450 mAh g −1 when reverting the discharge/charge current to 234 mA g −1 . It is demonstrated that natural graphite has important effect on the electrochemcial performance of the composite electrode, and an appropriate amount of natural graphite is beneficial to reduce the charge transfer resistance and maintain stable charge transfer process in cycling. [ABSTRACT FROM AUTHOR]

Highlight: [•] we fabricated Li3VO4/Ni composite via a unique two-step method [•] the Li3VO4/Ni electrode shows good cycle stability and rate capability [•] the Li3VO4/Ni electrode shows stable charge transfer and Li-ion diffusion coefficient [•] the Li3VO4/Ni electrode shows highly reversible lithiation/delithiation process [ABSTRACT FROM AUTHOR]

Highlights: [•] We prepared Cu2O–Cu composite architecture via an electrochemical corrosion method. [•] We explored the utilization of electrochemical corrosion of metal in Li-ion batteries. [•] The obtained Cu2O–Cu electrode shows excellent cycle stability and rate capability. [•] The effect of corrosion condition on electrochemical performance of Cu2O–Cu was studied. [ABSTRACT FROM AUTHOR]

Abstract: Novel massif-like Cu x O nanostructure was directly growing on Cu foam via a facile thermal oxidation method in air atmosphere. The massifs are about 5μm in mean diameter and 4μm in mean height, which consist of a large number of nanoparticles with mean size about 100nm. Cu x O nanowires that evolve from the particles locate at the laps of the massifs. Galvanostatic battery testing shows that the Cu x O/Cu electrode exhibits excellent cycle stability and rate capability. The charge and discharge capacities are both 1.8mAhcm−2 after 100 cycles under a discharge/charge rate of 0.35C. After testing at various rates from 0.2 to 12C over 50 cycles, the 5th-cycle discharge capacity can resume well when lowering the discharge/charge rate to 0.2C. The performances are testified due to a novel electrochemical activation effect that induces the reconstruction of porous forest-like morphology in cycling. [Copyright &y& Elsevier]

Abstract: Porous NiO/Ni foam electrode is fabricated by a simple two-step method. Firstly, nickel hydroxide hydrate nanoflakes are deposited on Ni foam via a chemical liquid deposition (CLD) method. Then NiO/Ni architecture is obtained by subsequent graft growth in air atmosphere at 350°C. Galvanostatic battery testing shows that NiO electrode exhibits fine capacity retention and good rate performance. It exhibits high initial discharge and charge capacity of 1.94 and 1.36mAhcm−2, maintaining of 1.41 and 1.38mAhcm−2 after 140 cycles under a discharge/charge rate of 0.4C. It delivers high discharge capacity retention of 70% (comparing with that of 0.2C) even at a high rate of 2.5C. After that, the discharge capacity can gradually resume along with the decrease of discharge/charge rate, showing capacity retention of 105% when lowering the discharge/charge rate to 0.2C. The fine electrochemical performance of NiO/Ni is due to the maintenance of porous architecture and the prevention of active nano-sized NiO from aggregation in cycling, which is relevant to both the interweaved structure of NiO nanoflakes and the graft growth between NiO and Ni. [Copyright &y& Elsevier]