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Rational design and synthesis processes are very important for giving a product an excellent performance. Sn-based anode materials with a high theoretical capacity and suitable working potential usually suffer from severe capacity fading due to their inferior electronic conductivity and obvious volumetric variations, hindering their practical applications. Herein, hierarchical N doped graphene-supported SnO2/Zn2SnO4 (SnO2/Zn2SnO4-NG) is successfully prepared via a facile approach forming a 3D hierarchical configuration. As an anode for lithium-ion batteries, the SnO2/Zn2SnO4-NG anode can reach a high reversible capacity (837 mA h g−1 after 300 cycles at 0.2 A g−1) and rate capability (403 mA h g−1 at 5 A g−1) but also show extraordinary durability. Furthermore, it exhibits an impressive rate performance and maintains superior cycling stability. Such significantly enhanced electrochemical performances of the SnO2/Zn2SnO4-NG anode can be attributed to the unique structural design, which can not only effectively reduce the stress from the discharging/charging process and maintain the structural stability of the electrode during cycling but also alleviate aggregation of the active materials and facilitate electrolyte/ion transport. Meanwhile, Zn2SnO4 can greatly improve the electrical conductivity (confirmed by DFT calculations), and SnO2/Zn2SnO4 can create more active sites for lithium storage. This work thus verifies the great potential of the SnO2/Zn2SnO4-NG composite for applications as a high-performance anode material in next-generation Li storage. [ABSTRACT FROM AUTHOR]

A high sulfur loading cathode strengthened by using carbon fiber (CF) is achieved via a typical coating method. Interlaced fibers and abundant hairline cracks ensure an unobstructed electron transfer path and sufficient Li-ion transport channels. The CF-sewed electrode with sulfur loading up to 10 mg cm−2 delivers a high areal capacity of over 7 mA h cm−2 after 96 cycles with a high coulombic efficiency over 99%. [ABSTRACT FROM AUTHOR]

Herein, Cu-doped Co-ZIF nanoplate arrays are uniformly grown on a commercial paper towel substrate first. After a subsequent annealing treatment, well-defined Cu-doped Co/CoO nanoparticles embedded in N-doped carbon hybrid nanoplate arrays supported on the carbon paper substrate (denoted as Cu-doped Co/CoO/NC NPAs@CP) are obtained, which exhibit excellent performance as a low-cost, lightweight and binder-free anode for lithium ion storage. [ABSTRACT FROM AUTHOR]

Here, we wrap Co3O4 nanoparticles with nitrogen-doped graphitic carbon nanofibers (Co3O4@NGFs) as a self-standing electrode for lithium-ion batteries. In this structure, graphitic carbon acts as a composite framework that enhances conductivity, accommodates volume expansion and increases contact with the electrolyte. Meanwhile, the porosity of Co3O4@NGFs not only facilitates rapid electron transfer, but also exposes more active sites for lithium storage. [ABSTRACT FROM AUTHOR]

Phase separation and electronic structure variation of Li0.5FePO4, both in the bulk and surface, under concurrent lithiation, has been tracked by synchrotron X-ray microscopies. Oxygen K-edge XANES along with DFT calculations reveal unusual electronic structure varition which is attributable to the observed lithium gradient and interparticle transport. The new insights will benefit the future design of advanced batteries. [ABSTRACT FROM AUTHOR]

A V2O5 porous nanodisk thin film is synthesized through a simple hydrothermal and subsequent VO2 template oxidation strategy. For the first time, V2O5 is employed as a cathode rather than an anode to construct lithium-ion hybrid capacitors. This design effectively utilizes the intrinsic layered structure of V2O5 for facile Li+ intercalation and facilitates the charge balance with the capacitive electrode, enabling superior performance of the device. [ABSTRACT FROM AUTHOR]

Cation order, with a local structure related to γ-LiFeO2, is observed in the nominally cation-disordered Li-excess rocksalt Li1.25Nb0.25Mn0.5O2via X-ray diffraction, neutron pair distribution function analysis, magnetic susceptibility and NMR spectroscopy. The correlation length of ordering depends on synthesis conditions and has implications for the electrochemistry of these phases. [ABSTRACT FROM AUTHOR]

Hierarchical ZnSn(OH)6/Zn2SnO4 yolk–shell nonspherical structures that are composed of self-supported nanowire arrays have been conveniently prepared via a simple secondary growth method. The XRD and TEM results indicate that the composition of the outer nanowire shell is the Zn2SnO4 (ZTO) phase, while the inner cubic core is the incomplete conversion ZnSn(OH)6 phase. Due to the synergistic effect of the low dimensional shell and stable yolk–shell structure, the as-obtained hierarchical ZnSn(OH)6/ZTO yolk–shell structures exhibit high stability and capacity for lithium ion batteries (LIBs). [ABSTRACT FROM AUTHOR]

We report the first direct measurement of the extent of the spontaneous non-electrochemically driven reaction between a lithium ion battery electrode surface (Si) and a liquid electrolyte (1.2 M LiPF6–3 : 7 wt% ethylene carbonate : dimethyl carbonate). This layer is estimated to be 35 Å thick with a SLD of ∼ 4 × 10−6Å−2 and likely originates from the consumption of the silicon surface. [ABSTRACT FROM AUTHOR]

LiNbO3 nanoplates were directly grown on a self-weaving CNT-network, which was then decorated with polypyrrole to form a flexible electrode. This novel nano-structured anode exhibits superior performance, i.e., high rate discharge capacity and excellent cycle performance. [ABSTRACT FROM AUTHOR]

Disordered and ordered forms of nano-Li[Ni0.5Mn1.5]O4 spinel, have been prepared by a one-pot resorcinol–formaldehyde synthesis. Lithium intercalation into disordered nano-Li[Ni0.5Mn1.5]O4−δ reveals good rate capability and cycling stability. It delivers 95.5% of the capacity at a rate of 10C (1500 mA g−1) and 88% at 20C (3000 mA g−1) compared with the capacity at low rate (0.2C). A capacity retention on cycling of 99.97% per cycle at 1C rate has also been observed. The superior electrochemical behaviour of disordered nano-Li[Ni0.5Mn1.5]O4−δ has been correlated with AC impedance data, which suggests a modified surface for the nanomaterial prepared using the resorcinol–formaldehyde route compared with micron sized materials prepared by conventional solid state synthesis. [ABSTRACT FROM AUTHOR]

Layered Li4NiTeO6 was shown to reversibly release/uptake ∼2 lithium ions per formula unit with fair capacity retention upon long cycling. The Li electrochemical reactivity mechanism differs from that of Li2MO3 and is rooted in the Ni4+/Ni2+ redox couple, that takes place at a higher potential than conventional LiNi1−xMnxO2 compounds. We explain this in terms of inductive effect due to Te6+ ions (or the TeO66− moiety). [ABSTRACT FROM AUTHOR]

Ellagic acid, a naturally occurring polyphenol, extracted from pomegranate husk, is found to be a very good organic electrode material for rechargeable lithium batteries with high reversible capacities of ∼450 and 200 mA h g−1 at C/10 and C/2.5 discharge rates, respectively; ex situ NMR studies reveal possible lithiation–delithiation modes at different stages of the charge–discharge process. [ABSTRACT FROM AUTHOR]