A new type of amino polar binder with 3D network flexibility structure for high energy Li-S batteries is synthesized and successfully used with commercial sulfur powder cathodes. The binder shows significant performance improvement in capacity retention and high potential for practical application, which arouse the battery community's interest in the commercial application of high energy Li-S battery.

A sustainable route from the biomass byproduct okara as a natural nitrogen fertilizer to high-content N-doped carbon sheets is demonstrated. The as-prepared unique structure exhibits high specific capacity (292 mAh g(-1) ) and extremely long cycle life (exceeding 2000 cycles). A full battery is devised for the practical use of materials with a flexible/wearable LED screen.

Sodium-ion battery (SIB) is especially attractive in cost-effective energy storage device as an alternative to lithium-ion battery. Particularly, metal phosphides as potential anodes for SIBs have recently been demonstrated owing to their higher specifi c capacities compared with those of carbonaceous materials. Unfortunately, most reported metal phosphides consist of irregular particles ranged from several hundreds nanometers to tens of micrometers, thus delivering limited cyclic stability. This paper reports the sodium storage properties of additive-free Cu 3 P nanowire (CPNW) anode directly grown on copper current collector via an in situ growth followed by phosphidation method. Therefore, as a result of its structure features, CPNW anode demonstrates highly stable cycling ability with an ≈70% retention in capacity at the 260th cycle, whereas most reported metal phosphides have limited cycle numbers ranged between 30 and 150. Besides, the reaction mechanism between Cu 3 P and Na is investigated by examining the intermediate products at different charge/discharge stages using ex situ X-ray diffraction measurements. Furthermore, to explore the practical application of CPNW anode, a pouch-type Na + full cell consisting of CPNW anode and Na 3 V 2 (PO 4 ) 3 cathode is assembled and characterized. As a demonstration, a 10 cm × 10 cm light-emmiting diode (LED) screen is successfully powered by the Na + full cell. Figure 6. a) Schematic representation of the pouch-type CPNW/NVP Na + full cell. b) Cycling performance of the CPNW/NVP Na + full cell at current densities of 600 mA g −1 . c,d) Optical images showing a fl exible LED screen powered by the pouch-type CPNW/NVP Na + full cell. wileyonlinelibrary.com

The electroreduction of nitrogen to ammonia offers a promising alternative to the energy-intensive Haber–Bosch process. Unfortunately, the reaction suffers from low activity and selectivity, owing to competing hydrogen evolution and the poor accessibility of nitrogen to the electrocatalyst. Here, we report that deliberately triggering a salting-out effect in a highly concentrated electrolyte can simultaneously tackle the above challenges and achieve highly efficient ammonia synthesis. The solute ions exhibit strong affinity for the surrounding H2O molecules, forming a hydration shell and limiting their efficacy as both proton sources and solvents. This not only effectively suppresses hydrogen evolution but also ensures considerable nitrogen flux at the reaction interface via heterogeneous nucleation of the precipitate, thus facilitating the subsequent reduction process in terms of both selectivity and activity. As expected, even when assembled with a metal-free electrocatalyst, a high Faradaic efficiency of 71 ± 1.9% is achieved with this proof-of-concept system.

In the quest to develop next generation lithium ion battery anode materials, satisfactory electrochemical performance and low material/fabrication cost are the most desirable features. In this article, porous Si nanowires are synthesized by a cost‐effective metal‐assisted chemical etching method using cheap metallurgical silicon as feedstock. More importantly, a thin oxide layer (≈3 nm) formed on the surface of porous Si nanowires stabilizes the cycling performance of lithium ion batteries. Such an oxide coating is able to constrain the huge volume expansion of the underlying Si, yet it is thin enough to ensure good permeability for both lithium ions and electrons. Therefore, the extraordinary storage capacity of Si can be well retained in prolonged electrochemical cycles. Specifically, Si/SiOx nanowires deliver a reversible capacity of 1503 mAh g−1 at the 560th cycle at a current density of 600 mA g−1, demonstrating an average of only 0.04% drop per cycle compared with its initial capacity. Furthermore, the highly porous structure and thin Si wall facilitate the electrolyte penetration and shorten the solid‐state lithium transportation path, respectively. As a result, stable and satisfactory reversible capacities of 1297, 976, 761, 548, and 282 mAh g−1 are delivered at current densities of 1200, 2400, 3600, 4800, and 7200 mA g−1, respectively.

Low utilization of active metallic sodium (Na) and uncontrollable growth of Na dendrites remain significant challenges for high-performance Na metal batteries, which are limited to inefficient Na utilization (<1%) and shallow cycling conditions (0.25–1.0 mAh cm–2). In this work, a kind of Na metal anode with record-high utilization and long-term cycling stability is reported, using carbon-substrate-supported nitrogen-anchored zinc (Zn) single atoms as a current collector. Single Zn atom sites which serve as a strong “magnet” for Na ions, can guide the metallic Na uniform nucleation and free from dendrite-induced short circuit. The nucleation overpotential of our strategy is essentially zero, where most of the reported modified substrates were greatly exceed 20 mV. Specifically, the Na anodes exhibit a high Na stripping/plating Coulombic efficiency with 99.8% over 350 cycles and a stable voltage response with small voltage hysteresis after cycling 1000 h. The full cell exhibits high Na utilization up to 100% and superior long-term cycling stability for more than 1000 cycles with excellent capacity retention. In terms of lifetime and Na utilization, the Na metal anodes based on our strategy significantly outperforms the reported state-of-the-art Na metal anodes. Moreover, this affords new insights into the controllable Na nucleation behavior and high Na utilization and sheds fresh light on atomic level design of an electrode for Na metal anodes.

The sluggish solid−solid conversion kinetics from Li 2 S 4 to Li 2 S during discharge is considered the main problem for cryogenic Li−S batteries. Herein, an all-liquidphase reaction mechanism, where all the discharging intermediates are dissolved in the functional thioether-based electrolyte, is proposed to significantly enhance the kinetics of Li−S battery chemistry at low temperatures. A fast liquidphase reaction pathway thus replaces the conventional slow solid−solid conversion route. Spectral investigations and molecular dynamics simulations jointly elucidate the greatly enhanced kinetics due to the highly decentralized state of solvated intermediates in the electrolyte. Overall, the battery brings an ultrahigh specific capacity of 1563 mAh g −1 sulfur in the cathode at −60 °C. This work provides a strategy for developing cryogenic Li−S batteries.

the capacity of batteries; 3) large volume changes during circulation process can tend to bring about the fragmentation of solid electrolyte interphase (SEI), exposing the fresh lithium metal inside that the electrolyte will continue to react with lithium metal to consume the electrolyte and the growth of dendrite cannot be effectively inhibited (Figure 1). [3-6] Several ways have been put forward to solve these problems, [7-9] but the proposed methods to improve the performance of LMBs still face several influence factors: 1) the solvation sheath of Li + in liquid electrolyte and the ion conductivity in both gel and solid electrolyte; 2) the formation and components of solid electrolyte interfaces (SEI); (3) the deposition behavior of Li + on the surface of anode. A detailed microscopic understanding of island growth mechanism is required to successful solve these problems. Recently, some advanced characterization methods (scanning electron microscope, cryo-transmission electron microscope and lots of in situ characterization technology such as in situ X-ray diffraction, in situ fourier transform infrared spectroscopy, in situ UV absorption spectroscopy [10-12]) and advanced electrochemical measurement (cyclic voltammetry, impedance test, magnification test, exchange current density, and polarization test [13-16]) have been employed to figure out the dynamic behavior of different models. However, these characterizations and measurements are only focused on the description of test results in the level of phenomenon, lack of rational explanation. Many applications still need physical theoretical analysis to comprehend their kinetics mechanism, where molecular dynamics simulation can be used to strengthen the insights into the mechanism investigation of LMBs. [17] With the development of computational simulation technique such as Density Functional Theory (DFT) and Finite element simulation, molecular dynamics (MD) is one of the most frequently-used computational simulations in many fields. It is a science of simulating the motions of particles in system which combines with physics, mathematics and chemistry. Therefore, it can help researchers understand properties of assemblies of molecules by calculating the forces under different interaction potentials. Generally speaking, MD simulate can be divided into classic molecular dynamics (CMD) under Newtonian equation, reactive molecular dynamics (RMD) under reaction force field, ab initio molecular dynamics (AIMD) under Schrodinger The Li metal battery is attracting more and more attention in the field of electric vehicles because of its high theoretical capacity and low electrochemical potential. But its inherent disadvantages including uncontrolled lithium dendrites, high chemical activity, and large volume changes hold back the large-scale application of stable Li metal anodes. Recently, various computational studies have been used to facilitate the rationalization of experimental observed phenomenon. In this review, the progress of molecular dynamics simulations i...