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High Li+ transference number electrolytes have long been understood to provide attractive candidates for realizing uniform deposition of Li+. However, such electrolytes with immobilized anions would result in incomplete solid electrolyte interphase (SEI) formation on the Li anode because it suffers from the absence of appropriate inorganic components entirely derived from anions decomposition. Herein, a boron‐rich hexagonal polymer structured all‐solid‐state polymer electrolyte (BSPE+10% LiBOB) with regulated intermolecular interaction is proposed to trade off a high Li+ transference number against stable SEI properties. The Li+ transference number of the as‐prepared electrolyte is increased from 0.23 to 0.83 owing to the boron‐rich cross‐linker (BC) addition. More intriguingly, for the first time, the experiments combined with theoretical calculation results reveal that BOB− anions have stronger interaction with B atoms in polymer chain than TFSI−, which significantly induce the TFSI− decomposition and consequently increase the amount of LiF and Li3N in the SEI layer. Eventually, a LiFePO4|BSPE+10% LiBOB|Li cell retains 96.7% after 400 cycles while the cell without BC‐resisted electrolyte only retains 40.8%. BSPE+10% LiBOB also facilitates stable electrochemical cycling of solid‐state Li‐S cells. This study blazes a new trail in controlling the Li+ transport ability and SEI properties, synergistically. [ABSTRACT FROM AUTHOR]

The Li dendrite growth and the liquid electrolyte volatilization under semi-open architecture are intrinsic issues for Li-O2 battery. In this work, we propose a non-Newtonian fluid quasi-solid electrolyte (NNFQSE) SiO2-SO3Li/PVDF-HFP, which has both shear-thinning and shear-thickening properties. The component interactions among the sulfonated silica nanoparticles, liquid electrolyte, and polymer network are beneficial for decent Li+ conductivity and high liquid electrolyte retention without volatilization. Furthermore, NNFQSE exhibits shear-thinning property to eliminate the stress of dendrite growth during repeated cycling. Meanwhile, when the force suddenly increases, such as a high current rate, the NNFQSE may dynamically turn shear-thickening to respond and mechanically stiffen to inhibit the lithium dendrite penetration. By coupling with the NNFQSE, the lithium symmetrical battery can run over 2000 h under 1 mA cm−2 at room temperature, and the quasi-solid Li-O2 battery actualizes long life above 5000 h at 100 mA g−1. Lithium dendrite growth and liquid electrolyte volatilization limit the further development of lithium-oxygen batteries. Here, authors report a non-Newtonian fluid quasi-solid electrolyte to address those issues, which improve the life duration of the lithium-oxygen batteries. [ABSTRACT FROM AUTHOR]

A high-performance Ni/Mo co-doped lithium manganate composite material, LiNi0.03Mo0.01Mn1.96O4, is prepared by a solid-state method, then a biomass-derived carbon layer with ethyl cellulose as the carbon source is applied to the surface of the composite particles. We find that carbon layer with the proper loading can significantly enhance the material's cyclic stability and capacity at high discharge rates. At rates of 5C and 10C, our optimal sample (LNMMO-3wt%C), with 3 wt% carbon layer loading, has discharge capacities up to 114 and 98 mAh g−1, respectively, which are 10 and 8% higher than those of the uncoated co-doped material. Further, the carbon layer coating significantly improves the material's stability at high discharge rates: the capacity retention of LNMMO-3wt%C after 400 cycles at discharge rates of 5C and 10C is high reaching 93.6 and 88.1%, respectively, compared with 91.4 and 74.3% for uncoated LNMMO. Based on our experimental results and analysis, we attribute the enhanced stability and capacity at high discharge rates to two factors: (i) enhanced conductivity and (ii) reduced Mn3+ dissolution, combined with significantly decreased resistance from Li+ ion intercalation/de-intercalation, due to the uniformity of the carbon layer coating.Ni/Mo-doped lithium manganate, LiNi0.03Mo0.01Mn1.96O4, is coated with carbon layer by using biomass-based feedstock ethyl cellulose (EC) as carbon source. The carbon layer coating results significantly improved stability at high discharging rates: the capacity retention of our optimal sample (LNMMO-3wt%C) material after 400 cycles at discharging rates of 5C and 10C are high up to 93.6 and 88.1%, respectively, compared with 91.4 and 74.3% for uncoated material. [ABSTRACT FROM AUTHOR]

Liu, L.; Song, H.; and Xing, J., 2019. Benchmarking of marine equipment manufacturing industry in Liaoning province. In: Gong, D.; Zhu, H., and Liu, R. (eds.), Selected Topics in Coastal Research: Engineering, Industry, Economy, and Sustainable Development. Journal of Coastal Research, Special Issue No. 94, pp. 838–841. Coconut Creek (Florida), ISSN 0749-0208. This article constructs an evaluation index system for the competitiveness of marine equipment manufacturing industry from six aspects: industrial scale, economic benefits, international competitiveness, asset management capabilities, innovation capabilities, and social benefits. And it is measured by 14 relatively objective, complete, and quantifiable indicators. Taking the marine equipment manufacturing industry in 12 provinces and cities such as Liaoning, Jiangsu, Shandong, Guangdong, Shanghai and Zhejiang as the research object, quantify this approach of the competitiveness level of seven sub-sectors in the selected 12 provinces and cities in the marine equipment manufacturing industry based on competitive evaluation theory, then comprehensively evaluated and simply sorted, and based on the research to calculate results. Finally, identify the provinces and cities which has characteristics of individual advantage of competitiveness level. As a benchmark province, which will compare the competitive status with that of Liaoning's marine equipment manufacturing industry in order to find out the gaps and identify the reasons. [ABSTRACT FROM AUTHOR]

A high voltage cathode material, LiNi0.5Mn1.5O4, is synthesized with a two-step approach, in which the nickel–manganese oxalate precipitate is firstly obtained by adding oxalic acid to the solution of nickel and manganese ions precursors, followed by calcining the oxalates to obtain spinel nickel–manganese oxide, incorporating lithium ions with ball milling and calcining at 900 °C for 15 h. The materials are characterized with TG, XRD, SEM, BET and FTIR; it is revealed that both nickel–manganese oxide and final LiNi0.5Mn1.5O4 have well defined spinel structure. The LiNi0.5Mn1.5O4 spinel materials exhibit high capacities and good cyclic stability, the capacity of the materials is in the range from 126 to 136 mAh −1, depending on the calcining temperatures. The sample calcined at an optimal temperature of 900 °C exhibits best performance, the capacity is high up to 136 mAh g−1 at tenth cycle and the capacity retention after 50 cycles is 93%. For the sample prepared by mixing and milling oxalate with lithium salt, the discharge capacity is only 115 mAh g−1. We suggest that the spinel oxide derived from oxalate may play an important role for the high performance and high stability of the final cathode materials. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries (LSBs) are considered one of the most promising candidates for next-generation energy storage owing to their large energy capacity. Tremendous effort has been devoted to overcoming the inherent problems of LSBs to facilitate their commercialization, such as polysulfide shuttling and dendritic lithium growth. Pouch cells present additional challenges for LSBs as they require greater electrode active material utilization, a lower electrolyte-sulfur ratio, and more mechanically robust electrode architectures to ensure long-term cycling stability. In this review, the critical challenges facing practical Li-S pouch cells that dictate their energy density and long-term cyclability are summarized. Strategies and perspectives for every major pouch cell component-cathode/anode active materials and electrode construction, separator design, and electrolyte-are discussed with emphasis placed on approaches aimed at improving the reversible electrochemical conversion of sulfur and lithium anode protection for high-energy Li-S pouch cells.