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Manganese-based layered oxides are one of the most promising cathodes for Na-ion batteries, but the prospect of their practical application is challenged by high sensitivity to ambient air. The stacking structure of materials is critical to the aging mechanism between layered oxides and air, but there remains a lack of systematic study. Herein, comprehensive research on model materials P-type Na

As high capacity cathodes, O3-type Na-based oxides always suffer from a series of monoclinic transitions upon sodiation/desodiation, mainly caused by Na+/vacancy ordering and Jahn–Teller (J−T) dist...

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the DArk Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of $4.3\sigma$. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out., Comment: 11 pages, 13 figures, published in Phys. Rev. Lett. Add one more digit for first three columns in Table S2

The development of new sodium ion battery (SIB) cathodes with satisfactory performance requires an in-depth understanding of their structure−function relationships, to rationally design better electrode materials. In this work, highly ordered, honeycomb-layered Na3Ni2SbO6 was prepared to elucidate the structural evolution and Na+ kinetics during electrochemical desodiation/sodiation processes. Structural analysis involving in situ synchrotron X-ray diffraction (XRD) experiments, electrochemical performance measurements, and electrochemical characterization (galvanostatic intermittent titration technique, GITT) methods were used to obtain new insights into the reaction mechanism controlling the (de)intercalation of sodium into the host Na3−xNi2SbO6 structure. Two phase transitions occur (initial O′3 phase → intermediate P′3 phase → final O1 phase) upon Na+ extraction; the partial irreversible O′3-P′3 phase transition is responsible for the insufficient cycling stability. The fast Na+ mobility (average 10–12 cm2·s–1) in the interlayer, high equilibrium voltage (3.27 V), and low voltage polarization (50 mV) establish the linkage between kinetic advantage and a good rate performance of the cathode. These new findings provide deep insight into the reaction mechanism operating in the honeycomb cathode; the present approach could be also extended to investigate other materials for SIBs.

Summary The aspiration of employing metallic lithium (Li) as the anode is impeded by Li dendrites and unwanted redox shuttles in liquid electrolytes. In this study, a repellent used to safeguard the Li anode was demonstrated during the lithiation of a nanosized AlPO4 additive in an infiltrated quasi-solid electrolyte (i-QSE) containing a concentrated electrolyte in a poly(tri-acrylate) network. As a result of the infiltrated structure, the ion transfer number of i-QSE attained 0.79, and the activation energy was only 0.12 eV. Compared with the control counterpart, the repellent composed of Al-containing (oxy)fluorides played a vital role in stabilizing the interface and promoted the cycling durability of batteries (capacity retention >85% after 200 cycles) with a 1 C rate at an elevated temperature (55°C) without dendrite growth and by-product drifting. Such in situ generation of a repellent for a Li anode is a valid approach for metal-anode protection at the interface-engineering level.

DAMPE satellite has directly measured the cosmic ray proton spectrum from 40 GeV to 100 TeV and revealed a new feature at about 13.6 TeV., The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 1/2 years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.

A novel P2-type Na2/3Ni1/6Mg1/6Ti2/3O2 material is explored as an anode for sodium-ion batteries (SIBs) for the first time. It delivers a reversible capacity of 92 mA h g-1 with a safe average storage voltage of approximately 0.7 V in a sodium half-cell, and exhibits good cycle stability (ca. 87.4% capacity retention for 100 cycles) at a cut-off voltage of 0.2-2.5 V, indicating its superiority as a promising candidate anode material for SIBs.

A subzero-temperature cathode material is obtained by nucleating cubic prussian blue crystals at inhomogeneities in carbon nanotubes. Due to fast ionic/electronic transport kinetics even at -25 °C, the cathode shows an outstanding low-temperature performance in terms of specific energy, high-rate capability, and cycle life, providing a practical sodium-ion battery powering an electric vehicle in frigid regions.

A novel organosilicon-based ionic plastic crystal, N,N,N,-diethylmethyl-N-[(trimethylsilyl)methyl]ammonium bistrifluoromethane sulfonimide ([DTMA][TFSI]) was designed and synthesized as solid-state electrolyte for lithium-ion batteries. The chemical structure and the physical and electrochemical properties were characterized in detail. The ionic conductivity of [DTMA][TFSI] was improved significantly by doping with lithium oxalyldifluoroborate (LiODFB) and propylene carbonate (PC). An optimized plastic crystal composite ([DTMA][TFSI]:LiODFB:PC=8:1:1 in molar ratio) as a solid-state electrolyte exhibited a decent cycling stability in LiFePO4/Li half-cell, with a specific discharge capacity of 144 mA·h/g and capacity retention of 94% after 50 cycles at C/20.

The DArk Matter Particle Explorer (DAMPE), a satellite-based cosmic ray and gamma-ray detector, was launched on December 17, 2015, and began its on-orbit operation on December 24, 2015. In this work we document the on-orbit calibration procedures used by DAMPE and report the calibration results of the Plastic Scintillator strip Detector (PSD), the Silicon-Tungsten tracKer-converter (STK), the BGO imaging calorimeter (BGO), and the Neutron Detector (NUD). The results are obtained using Galactic cosmic rays, bright known GeV gamma-ray sources, and charge injection into the front-end electronics of each sub-detector. The determination of the boundary of the South Atlantic Anomaly (SAA), the measurement of the live time, and the alignments of the detectors are also introduced. The calibration results demonstrate the stability of the detectors in almost two years of the on-orbit operation.

The uncontrolled growth of Li dendrites upon cycling might result in low coulombic efficiency and severe safety hazards. Herein, a lithiophilic binary lithium-aluminum alloy layer, which was generated through an in situ electrochemical process, was utilized to guide the uniform metallic Li nucleation and growth, free from the formation of dendrites. Moreover, the formed LiAl alloy layer can function as a Li reservoir to compensate the irreversible Li loss, enabling long-term stability. The protected Li electrode shows superior cycling over 1700 h in a Li|Li symmetric cell.

As one of the most fascinating cathode candidates for Na-ion batteries (NIBs), P2-type Na layered oxides usually exhibit various single-phase domains accompanied by different Na+/vacancy-ordered superstructures, depending on the Na concentration when explored in a limited electrochemical window. Therefore, their Na+ kinetics and cycling stability at high rates are subjected to these superstructures, incurring obvious voltage plateaus in the electrochemical profiles and insufficient battery performance as cathode materials for NIBs. We show that this problem can be effectively diminished by reasonable structure modulation to construct a completely disordered arrangement of Na-vacancy within Na layers. The combined analysis of scanning transmission electron microscopy, ex situ x-ray absorption spectroscopy, and operando x-ray diffraction experiments, coupled with density functional theory calculations, reveals that Na+/vacancy disordering between the transition metal oxide slabs ensures both fast Na mobility (10-10 to 10-9 cm2 s-1) and a low Na diffusion barrier (170 meV) in P2-type compounds. As a consequence, the designed P2-Na2/3Ni1/3Mn1/3Ti1/3O2 displays extra-long cycle life (83.9% capacity retention after 500 cycles at 1 C) and unprecedented rate capability (77.5% of the initial capacity at a high rate of 20 C). These findings open up a new route to precisely design high-rate cathode materials for rechargeable NIBs.

Energy storage devices are more important today than any time before in human history due to the increasing demand for clean and sustainable energy. Rechargeable batteries are emerging as the most efficient energy storage technology for a wide range of portable devices, grids and electronic vehicles. Future generations of batteries are required to have high gravimetric and volumetric energy, high power density, low price, long cycle life, high safety and low self-discharge properties. However, it is quite challenging to achieve the above properties simultaneously in state-of-the-art single metal ion batteries (e.g. Li-ion batteries, Na-ion batteries and Mg-ion batteries). In this contribution, hybrid-ion batteries in which various metal ions simultaneously engage to store energy are shown to provide a new perspective towards advanced energy storage: by connecting the respective advantages of different metal ion batteries they have recently attracted widespread attention due to their novel performances. The properties of hybrid-ion batteries are not simply the superposition of the performances of single ion batteries. To enable a distinct description, we only focus on dual-metal-ion batteries in this article, for which the design and the benefits are briefly discussed. We enumerate some new results about dual-metal-ion batteries and demonstrate the mechanism for improving performance based on knowledge from the literature and experiments. Although the search for hybrid-ion batteries is still at an early age, we believe that this strategy would be an excellent choice for breaking the inherent disadvantages of single ion batteries in the near future.

Rechargeable magnesium batteries have attracted recent research attention because of abundant raw materials and their relatively low-price and high-safety characteristics. However, the sluggish kinetics of the intercalated Mg(2+) ions in the electrode materials originates from the high polarizing ability of the Mg(2+) ion and hinders its electrochemical properties. Here we report a facile approach to improve the electrochemical energy storage capability of the Li4 Ti5 O12 electrode in a Mg battery system by the synergy between Mg(2+) and Li(+) ions. By tuning the hybrid electrolyte of Mg(2+) and Li(+) ions, both the reversible capacity and the kinetic properties of large Li4 Ti5 O12 nanoparticles attain remarkable improvement.

We develop a strategy to improve the electrochemical properties of red P by controlling the sodiation reaction to form NaxPy intermediates rather than the complete sodiation product of Na3P. The resultant red P@carbon nanocomposite shows a highly stable cyclability (capacity retention > 88% after 200 cycles), excellent rate capability, and high capacity for sodium storage.

We demonstrate that Na+/vacancy disordering of P2-type layered cathodes ensures both fast Na mobility and a low Na diffusion barrier., As one of the most fascinating cathode candidates for Na-ion batteries (NIBs), P2-type Na layered oxides usually exhibit various single-phase domains accompanied by different Na+/vacancy-ordered superstructures, depending on the Na concentration when explored in a limited electrochemical window. Therefore, their Na+ kinetics and cycling stability at high rates are subjected to these superstructures, incurring obvious voltage plateaus in the electrochemical profiles and insufficient battery performance as cathode materials for NIBs. We show that this problem can be effectively diminished by reasonable structure modulation to construct a completely disordered arrangement of Na-vacancy within Na layers. The combined analysis of scanning transmission electron microscopy, ex situ x-ray absorption spectroscopy, and operando x-ray diffraction experiments, coupled with density functional theory calculations, reveals that Na+/vacancy disordering between the transition metal oxide slabs ensures both fast Na mobility (10−10 to 10−9 cm2 s−1) and a low Na diffusion barrier (170 meV) in P2-type compounds. As a consequence, the designed P2-Na2/3Ni1/3Mn1/3Ti1/3O2 displays extra-long cycle life (83.9% capacity retention after 500 cycles at 1 C) and unprecedented rate capability (77.5% of the initial capacity at a high rate of 20 C). These findings open up a new route to precisely design high-rate cathode materials for rechargeable NIBs.

As promising high-capacity cathode materials for Na-ion batteries, O3-type Na-based metal oxides always suffer from their poor air stability originating from the spontaneous extraction of Na and oxidation of transition metals when exposed to air. Herein, a combined structure modulation is proposed to tackle concurrently the two handicaps via reducing Na layers spacing and simultaneously increasing valence state of transition metals. Guided by density functional theory calculations, we demonstrate such a modulation can be subtly realized through cosubstitution of one kind of heteroatom with comparable electronegativity and another one with substantially different Fermi level, by adjusting the structure of NaNi0.5Mn0.5O2 via Cu/Ti codoping. The as-obtained NaNi0.45Cu0.05Mn0.4Ti0.1O2 exhibits an increase of 20 times in stable air-exposure period and 9 times in capacity retention after 500 cycles, and even retains its structure and capacity after being soaked in water. Such a simple and effective structure mo...

A novel P2-type Na

Sodium-ion batteries (SIBs) have been considered as potential candidates for stationary energy storage because of the low cost and wide availability of Na sources. O3-type layered oxides have been considered as one of the most promising cathodes for SIBs. However, they commonly show inevitable complicated phase transitions and sluggish kinetics, incurring rapid capacity decline and poor rate capability. Here, a series of sodium-sufficient O3-type NaNi

Na-ion batteries are promising for large-scale energy storage applications, but few cathode materials can be practically used because of the significant difficulty in synthesizing an electrode material with superior comprehensive performance. Herein, an effective strategy based on synergetic contributions of rationally selected metal ions is applied to design layered oxides with excellent electrochemical performances. The power of this strategy is demonstrated by the superior properties of as-obtained NaFe0.45Co0.5Mg0.05O2 with 139.9 mA h g−1 of reversible capacity, 3.1 V of average voltage, 96.6% of initial Coulombic efficiency, and 73.9 mA h g−1 of capacity at 10 C rate, which benefit from the synergetic effect of Fe3+ (high redox potential), Co3+ (good kinetics), and inactive Mg2+ with compatible radii (stabilizing structure). Moreover, it is clarified that the superior property is not the simple superposition of performance for layered oxides with single metal ions. With the assistance of density functional theory calculations, it is evidenced that the wide capacity range (>70%) of prismatic Na+-occupied sites during sodiation/desodiation is responsible for its high rate performance. This rational strategy of designing high-performance cathodes based on the synergetic effect of various metal ions might be a powerful step forward in the development of new Na-ion-insertion cathodes.

Sodium-ion batteries (SIBs) have been considered as potential candidates for stationary energy storage because of the low cost and wide availability of Na sources. O3-type layered oxides have been considered as one of the most promising cathodes for SIBs. However, they commonly show inevitable complicated phase transitions and sluggish kinetics, incurring rapid capacity decline and poor rate capability. Here, a series of sodium-sufficient O3-type NaNi0.5 Mn0.5-x Ti x O2 (0 ≤ x ≤ 0.5) cathodes for SIBs is reported and the mechanisms behind their excellent electrochemical performance are studied in comparison to those of their respective end-members. The combined analysis of in situ X-ray diffraction, ex situ X-ray absorption spectroscopy, and scanning transmission electron microscopy for NaNi0.5 Mn0.2 Ti0.3 O2 reveals that the O3-type phase transforms reversibly into a P3-type phase upon Na+ deintercalation/intercalation. The substitution of Ti for Mn enlarges interslab distance and could restrain the unfavorable and irreversible multiphase transformation in the high voltage regions that is usually observed in O3-type NaNi0.5 Mn0.5 O2 , resulting in improved Na cell performance. This integration of macroscale and atomicscale engineering strategy might open up the modulation of the chemical and physical properties in layered oxides and grasp new insight into the optimal design of high-performance cathode materials for SIBs.

Recent progress in improving Li-S batteries' cathodes, anodes, and electrolytes via different approaches is summarized. The poor conductivity of sulfur cathodes, the dissolution of polysulfide intermediates, and the high reactivity of metal Li anodes currently motivate a great deal of research. Urgent challenges concerning Li anodes are also emphasized.

Size-related properties of novel lithium battery materials, arising from kinetics, thermodynamics, and newly discovered lithium storage mechanisms, are reviewed. Complementary experimental and computational investigations of the use of the size effects to modify electrodes and electrolytes for lithium ion batteries are enumerated and discussed together. Size differences in the materials in lithium ion batteries lead to a variety of exciting phenomena. Smaller-particle materials with highly connective interfaces and reduced diffusion paths exhibit higher rate performance than the corresponding bulk materials. The thermodynamics is also changed by the higher surface energy of smaller particles, affecting, for example, secondary surface reactions, lattice parameter, voltage, and the phase transformation mechanism. Newly discovered lithium storage mechanisms that result in superior storage capacity are also briefly highlighted.