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Ni-rich layered oxide cathode materials LiNixCoyMnzO2 (x>0.6) have been widely used in high specific energy Li-ion batteries. Compared with polycrystalline LiNixCoyMnzO2, single crystal Ni-rich cathode materials have attracted much attention for their unique advantages. However, they also suffer from some drawbacks, such rapid capacity decay and intragranular crack during cycling. In order to enhance the structure and electrochemical performance of single crystal LiNi0.8Co0.1Mn0.1O2 (SC811), different amount of aluminium (1 mol%, 2 mol% and 3 mol%) is utilized to substitute the materials. Physical characterizations of SC811 show the successful synthesis and Al doping of the single-crystal materials as well as lower Li/Ni intermixing after Al doping. Electrochemical tests illustrate that the single-crystal materials doped with 2mol% Al (2Al-SC811) shows superior electrochemical performance, and maintains 83.5 % of the initial discharge capacity after 100 cycles at 1 C in comparison with 68.9 % of the pristine SC811. It is hoped this work should shed light on the development of advanced cathode materials for Li-ion batteries.

Silicon anode is a promising candidate as an alternative to the conventional graphitic anode in lithium-ion batteries. In this work, silicon anode is modified by NH4F using a facile method in air. The concentration of NH4F on the electrochemical performance is systematically checked. The 5wt%NH4F-modified silicon anode exhibits enhanced cycle and rate performances, the first discharge specific capacity is 3958 mAh·g-1 with 86.45% as the coulombic efficiency at 0.4A·g-1. The capacity can maintain at 703.3 mAh·g-1 after 50 cycles, exhibiting a much better cycle stability than pristine silicon anode (329.9 mAh·g-1 after 50 cycles). SEM images confirm that NH4F can alleviate the volume expansion of silicon since LiF can be generated at the surface which is beneficial to the stability of solid-electrolyte interphase (SEI).

Nickel-rich layered oxides (Ni ≥60%) are considered as the most promising cathode materials for lithium-ion batteries due to its high energy density and low cost. However, its cycling performance is seriously influenced by the synthesis condition, like the sintering temperature, time and atmosphere. Herein, we investigate different properties of LiNi0.83Co0.11Mn0.06O2 (LNCMO) sintered from 720 to780 °C, and the cathode calcined at 760 °C display the most perfect layered structure and the uniform distribution of primary particles size. Therefore, the LNCMO sintered at 760 °C exhibited the best rate capability of 118 mAh·g-1 at 10 C and the highest capacity retention of 95.44 % after 100 cycles at 1 C. Our results indicate that the cycling performance and rate capability of LNCMO are heavily depended on the sintering temperature.

The PVDF/PVC blending membrane has a certain application in the field of sewage treatment. In this paper, the simulation study for the blending ratio of the PVDF/PVC membrane has been carried on, which has an influence on the membrane’s ability of sewage treatment. Firstly, the membrane models were constructed via Amorphous Cell module of MS (material studios) 6.0. Secondly, the optimization processes were achieved via Minimizer and MD (Molecular Dynamics) method of the Discover module. Lastly, the diffusion coefficientsDwas calculated indirectly through the Mean square displacement (MSD) getting from Forcite module and the solubility coefficientsSwas calculated indirectly through the adsorption isotherm getting from Sorption module. It was found that the membrane had a best ability of sewage treatment when the content of PVC was 5% (mass fraction). And the calculated result was well consistent with experiment result.

Virtual assembly was introduced in the chemical process simulation, and the method of virtual assembly for common chemical process was studied. The process of biomass fuel ethanol was analyzed which is combined by the first-grade distillation system in industrial ethanol production and the salt-added extractive distillation system in fuel ethanol production, and the scene graph structure was established. According to the assembly characteristics of the chemical process, the assembly equipment model was designed and constructed. The assembly points were added, and the assembly, simulation and transitive properties of the assembly points were defined. The 1+1and 1+n universality assembly method was proposed. By choosing unit equipment freely to assembly, the complex distillation system was realized. Results have shown that the assembly effect was good and accuracy, the method was proved correct and feasible. It is of great significance in the visual design of chemical process, digital construction of chemical plant and development of three-dimensional (3D) chemical process simulation technology.

The scene graph structure of Fischer-Tropsch synthesis (FTS) was constructed. In the meanwhile, the assembly unit model of equipment was designed. The main FTS reactor and its mathematical physical model were described. Platform for chemical process simulation was established, on base of the virtual assembly for FTS. The method of data transfer in common chemical process simulation was proposed. The composition and flow rate of components, as well as the temperature and pressure of the FTS reactor was investigated by the one dimensional quasi homogeneous model. The relative error is less than 3% between the calculation and experiment. The accuracy of the system process simulation is reliable. It is verified that the simulation method of chemical process is feasible on base of the virtual assembly. This work studies a new way for simulation of the FTS, and also provides technologic supports for the simulation of chemical process based on virtual assembly.

A simple strategy of pre-doping lithium ion into carbon negative electrode for lithium ion capacitor was introduced. In this strategy, a kind of Li-containing compound was added directly into the positive electrode of the lithium ion capacitor (LIC). When the lithium ion capacitor was charging first time, the Li-containing compound releases Li+, and the pre-doping of lithium ion into the negative electrode was performed. Here, we developed a lithium ion capacitor using Meso-carbon microbeads (MCMB)/activated carbon (AC) as the negative and positive electrode materials, respectively and use the lithium iron phosphate (LiFePO4) as the Li-containing compound, which supply the Li+ ions for pre-doping. The results demonstrated that, by adding 20 percent of LiFePO4 into the positive electrode, the efficiency of the capacitor increases from lower than 60% up to higher than 90%, and the capacitor shows good capacitance characteristics and high capacity.

Hydrous ruthenium oxide was synthesized by a sol-gel method on the surface of activated carbon (AC). After heat treatment at 150°C, the RuO2/AC composite was used as a positive electrode material in an alkaline electrochemical capacitor. Several composites with different Ru contents were prepared and studied. It was found that the composite containing 30 w/% Ru had a specific capacitance of about 333 F/g at a low current density, whereas that of the pure AC was only about 241 F/g. With an increase of Ru content, the spe-cific capacitance of the electrode increased correspondingly. When the Ru content exceeded 10 w/%, the specific capacitance contributed by RuO2·xH2O was about 440 F/g. The performance of the composite under the condition of high rate discharge was as good as that of the AC electrode.