Interpenetrated Gel Polymer Binder for High‐Performance Silicon Anodes in Lithium‐ion Batteries

Silicon has attracted ever‐increasing attention as a high‐capacity anode material in Li‐ion batteries owing to its extremely high theoretical capacity. However, practical application of silicon anodes is seriously hindered by its fast capacity fading as a result of huge volume changes during the charge/discharge process. Here, an interpenetrated gel polymer binder for high‐performance silicon anodes is created through in‐situ crosslinking of water‐soluble poly(acrylic acid) (PAA) and polyvinyl alcohol (PVA) precursors. This gel polymer binder with deformable polymer network and strong adhesion on silicon particles can effectively accommodate the large volume change of silicon anodes upon lithiation/delithiation, leading to an excellent cycling stability and high Coulombic efficiency even at high current densities. Moreover, high areal capacity of ～4.3 mAh/cm² is achieved based on the silicon anode using the gel PAA–PVA polymer binder with a high mass loading. In view of simplicity in using the water soluble gel polymer binder, it is believed that this novel binder has a great potential to be used for high capacity silicon anodes in next generation Li‐ion batteries, as well as for other electrode materials with large volume change during cycling.     

Stabilizing Polymer–Lithium Interface in a Rechargeable Solid Battery

Solid polymer electrolytes (SPEs) are promising candidates for developing high‐energy‐density Li metal batteries due to their flexible processability. However, the low mechanical strength as well as the inferior interfacial regulation of ions between SPEs and Li metal anode limit the suppress ion of Li dendrites and destabilize the Li anode. To meet these challenges, interfacial engineering aiming to homogenize the distribution of Li⁺/electron accompanied with enhanced mechanical strength by Mg₃N₂ layer decorating polyethylene oxide is demonstrated. The intermediary Mg₃N₂ in situ transforms to a mixed ion/electron conducting interlayer consisting of a fast ionic conductor Li₃N and a benign electronic conductor Mg metal, which can buffer the Li⁺ concentration gradient and level the nonuniform electric current distribution during cycling, as demonstrated by a COMSOL Multiphysics simulation. These characteristics endow the solid full cell with a dendrite‐free Li anode and enhanced cycling stability and kinetics. The innovative interface design will accelerate the commercial application of high‐energy‐density solid batteries.     

Oxygen Vacancies Evoked Blue TiO2(B) Nanobelts with Efficiency Enhancement in Sodium Storage Behaviors

Oxygen vacancies (OVs) dominate the physical and chemical properties of metal oxides, which play crucial roles in the various fields of applications. Density functional theory calculations show the introduction of OVs in TiO₂(B) gives rise to better electrical conductivity and lower energy barrier of sodiation. Here, OVs evoked blue TiO₂(B) (termed as B‐TiO₂(B)) nanobelts are successfully designed upon the basis of electronically coupled conductive polymers to TiO₂, which is confirmed by electron paramagnetic resonance and X‐ray photoelectron spectroscopy. The superiorities of OVs with the aid of carbon encapsulation lead to higher capacity (210.5 mAh g^?1 (B‐TiO₂(B)) vs 102.7 mAh g^?1 (W‐TiO₂(B)) at 0.5 C) and remarkable long‐term cyclability (the retention of 94.4% at a high rate of 10 C after 5000 times). In situ X‐ray diffractometer analysis spectra also confirm that an enlarged interlayer spacing stimulated by OVs is beneficial to accommodate insertion and removal of sodium ions to accelerate storage kinetics and preserve its original crystal structure. The work highlights that injecting OVs into metal oxides along with carbon coating is an effective strategy for improving capacity and cyclability performances in other metal oxide based electrochemical energy systems.     

Influence of sputtering conditions on the solar and luminous optical properties of amorphous LixWoy thin films

Thin films of amorphous tungsten oxide were deposited by sputtering onto glass substrates coated by conductive indium–tin oxide. The films were sputtered at different oxygen-to-argon flow ratios with different pressure and power. Elastic recoil detection analysis determined the density and the stoichiometry. X-ray diffraction measurements showed that the films were amorphous. The films were electrochemically intercalated with lithium ions. At several intercalation levels of each film, the optical reflectance and transmittance were measured in the wavelength range 0.3–2.5 μm. We study the effect of various sputtering conditions on the coloration efficiency of the films and on the luminous and solar optical properties. The O₂/Ar ratio and the sputter pressure determine to a large extent the optical absorption. As-deposited sputtered tungsten oxide with sufficiently little oxygen exhibits an absorption peak similar to the case of lithium intercalation.     

从盐湖卤水中提锂的研究进展

介绍了我国锂资源的一些基本概况,在此基础上比较了各种提锂方法,着重探讨了离子吸附法提锂的技术现状及相关发展趋势。     

从盐湖卤水中提锂的研究进展

介绍了我国锂资源的一些基本概况，在此基础上比较了各种提锂方法，着重探讨了离子吸附法提锂的技术现状及相关发展趋势。     

Active radiative liquid lithium divertor concept

Developing a reactor compatible divertor has been identified as a particularly challenging technology problem for magnetic confinement fusion. Application of lithium (Li) in NSTX resulted in improved H-mode confinement, H-mode power threshold reduction, and reduction in the divertor peak heat flux while maintaining essentially Li-free core plasma operation even during H-modes. These promising Li results in NSTX and related modeling calculations motivated the radiative liquid lithium divertor (RLLD) concept [1]. In the RLLD, Li is evaporated from the liquid lithium (LL) coated divertor strike point surface due to the intense heat flux. The evaporated Li is readily ionized by the plasma due to its low ionization energy, and the poor Li particle confinement near the divertor plate enables ionized Li ions to radiate strongly, resulting in a significant reduction in the divertor heat flux. This radiative process has the desired effect of spreading the localized divertor heat load to the rest of the divertor chamber wall surfaces, facilitating divertor heat removal. The modeling results indicated that the Li radiation can be quite strong, so that only a small amount of Li (∼a few mol/s) is needed to significantly reduce the divertor peak heat flux for typical reactor parameters. In this paper, we examine an active version of the RLLD, which we term ARLLD, where LL is injected in the upstream region of divertor. We find that the ARLLD has similar effectiveness in reducing the divertor heat flux as the RLLD, again requiring only a few mol/s of LL to significantly reduce the divertor peak heat flux for a reactor. An advantage of the ARLLD is that one can inject LL proactively even in a feedback mode to insure the divertor peak heat flux remains below an acceptable level, providing the first line of defense against excessive divertor heat loads which could result in damage to divertor PFCs. Moreover, the low confinement property of the divertor (i.e., <1 ms for Li particle confinement time) makes the ARLLD response fast enough to mitigate the effects of possible transient events such as large ELMs.     

Progress in development and application of lithium based components for Tokamak

Experiments with lithium plasma facing components (PFCs) show promising results for the operation of hot plasma facilities and the general improvement of plasma parameters. The design and development of new tokamak plasma facing material (PFM) based on lithium capillary porous systems (CPS) are described in this paper.The recent progress in the development of limiters with different kinds of CPS is relevant for protection of tokamak PFCs from damage under normal operation, ELMs and disruptions. New PFM eliminates the lithium flux into plasma, its pollution and lithium accumulation.Here we present an overview of the design and the experimental tests of the liquid lithium limiters. These limiters are based on CPS with hard matrix from stainless steel mesh, molybdenum and tungsten. Different types of limiter have been taken into account: the horizontal and vertical rail type limiters with passive and active cooling for investigation the possibility to provide the closed lithium circulation in tokamak chamber; the ring CPS-based limiter for investigation of lithium behavior in limiter scrape-off layer (SOL).Here we also present the preliminary results of the application of the cryogenic techniques for lithium removal from the chamber wall after operation in hot plasma.     

Simple self-assembly of SnS2 entrapped graphene aerogel and its enhanced lithium storage performance

In this work, SnS₂ nanoplates entrapped graphene aerogel has been successfully prepared by simple self-assembly of reduced graphene oxide obtained through mild chemical reduction. Structural and morphological investigations demonstrated that SnS₂ nanoplates are highly dispersed in the three dimensional (3D) porous graphene matrix. When served as anode material for lithium-ion batteries, the electrochemical properties of SnS₂/graphene aerogel (SnS₂/GA) were evaluated by galvanostatic discharge–charge tests, cyclic voltammetry and impedance spectroscopy measurement. Compared with pristine SnS₂, the SnS₂/GA nanocomposite achieved a much higher initial reversible capacity (1186 mAh g⁻¹), superior cyclic stability (1004 mAh g⁻¹ after 60 cycles, corresponding to 84.7% of the initial reversible capacity), as well as better rate capability (650 mAh g⁻¹ at a current density of 1000 mA g⁻¹). This significantly improved lithium storage performance can be attributed to the good integration of SnS₂ nanoplates with 3D porous graphene network, which can not only provide much more active sites and easy access for Li ions intercalation, but also prevent the aggregation of SnS₂ nanoplates and facilitate fast transportation of Li ions and surface electrons during the electrochemical process.     

低能耗熔盐电解金属锂电解槽的开发及研究

近年来,金属锂在全固态锂电池、铝锂合金制备中发挥着不可替代的价值,但金属锂生产成本仍然是生产企业需要解决的问题。因此,从降低能耗角度优化生产工艺及设备角度利用Solid Works三维建模电解槽结构,以及ANSYS仿真模拟软件对电解槽进行热场模拟及计算,得出最优设计方案。生产电解效率可达到91%,能耗在35 kWh/kg以下,抽氯和集锂装置可以自动运行,抽出氯气浓度90%,集锂效率可达到80%以上,且出锂量较为稳定。该设备可以更好的投入产业化生产,满足企业降低生产成本的需要,促进熔盐电解金属锂行业的发展。