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In this study, an electrode slurry composed of molybdenum disulfide (MoS2) and vapor-grown carbon fiber (VGCF) prepared through a solid-phase synthesis method was blade-coated onto copper foil to form a thick film as the anode for lithium-ion batteries. In previously reported work, MoS2-based lithium-ion batteries have experienced gradual deformation, fracture, and pulverization of electrode materials during the charge and discharge cycling process. This leads to an unstable electrode structure and rapid decline in battery capacity. Furthermore, MoS2 nanosheets tend to aggregate over charge and discharge cycles, which diminishes the surface activity of the material and results in poor electrochemical performance. In this study, we altered the density of the MoS2–carbon fiber/Cu foil anode electrode by rolling. Three different densities of electrode sheets were obtained through varying rolling repetitions. Our study shows the best electrochemical performance was achieved at a material density of 2.2 g/cm3, maintaining a capacity of 427 mAh/g even after 80 cycles. [ABSTRACT FROM AUTHOR]

We investigated the effectiveness of using methylboronic acid MIDA ester (ADM) as an additive in an electrolyte to enhance the overall electrochemical and material properties of an LNCAO (LiNi0.8Co0.15Al0.05O2) cathode. The cyclic stability of the cathode material measured at 40 °C (@ 0.2 C) showed an enhanced capacity of 144.28 mAh g−1 (@ 100 cycles), a capacity retention of 80%, and a high coulombic efficiency (99.5%), in contrast to these same properties without the electrolyte additive (37.5 mAh g−1, ~ 20%, and 90.4%), thus confirming the effectiveness of the additive. A Fourier transform infrared spectroscopy (FTIR) analysis distinctly showed that the ADM additive suppressed the EC-Li+ ion coordination (1197 cm−1 and 728 cm−1) in the electrolyte, thereby improving the cyclic performance of the LNCAO cathode. The cathode after 100 charge/discharge cycles revealed that the ADM-containing system exhibited better surface stability of the grains in the LNCAO cathode, whereas distinct cracks were observed in the system without the ADM in the electrolyte. A transmission electron microscopy (TEM) analysis revealed the presence of a thin, uniform and dense cathode electrolyte interface (CEI) film on the surface of LNCAO cathode. An operando synchrotron X-ray diffraction (XRD) test identified the high structural reversibility of the LNCAO cathode with a CEI layer formed by the ADM, which effectively maintained the structural stability of the layered material. The additive effectively inhibited the decomposition of electrolyte compositions, as confirmed by X-ray photoelectron spectroscopy (XPS). [ABSTRACT FROM AUTHOR]

In this study, a viscometer, which can measure the viscosity of low-volume liquids (25 μl) within 30 s, was developed on a centrifugal platform. The centrifugal viscometer consists of a disk platform and a motor. Under disk rotation, centrifugal, Coriolis, and viscosity-induced drag forces result in deflection of liquid flow. The viscosity of the liquid sample is determined by the deflection angle of the liquid, which can be examined through image analysis or visual inspection. The viscosities of a series of Newtonian model fluids were tested by the centrifugal viscometer and the results showed good agreement with the ones tested by a conventional rotational viscometer. Since the centrifugal viscometer only requires a motor to function, the microfluidic disk can be produced in large quantities at a low cost through injection molding, and the deflection angle can be detected through visual inspection, it provides an inexpensive, easy to operate, and portable approach to measure low-volume liquid viscosity. [ABSTRACT FROM AUTHOR]

Relative solid electrolyte interphase (SEI) film thickness investigation on graphite electrodes after the first charge state in the lithium‐ion battery was successfully demonstrated by the ex‐situ small‐angle neutron scattering technique. Here, for both the mesophase graphite powder (MGP) and the fine‐mesophase graphite powder (FMGP) anodes, with two different particle sizes was analyzed precisely by the Guinier–Porod model. The data revealed a stable, maximum (~tens of nm) bi‐layer SEI film formed on MGP anode in ethylene‐carbonate/dimethyl‐carbonate (EC/DMC) at a capacity of 50 mAh/g and sluggish above 100 mAhg‐1. The SEI formed on FMGP with and without 3 wt% fluoroethylene‐carbonate additive in EC/DMC showed the relative thickness greater than that only in ethylene‐carbonate/diethyl‐carbonate. Lithiation initiated the rapid SEI formation on the graphite surface and achieved a maximum thickness in the cell potential ≤0.2 V, and became thinner when the graphite particle expanded after Li+ intercalation. It was observed that the SEI thickness influenced the electrolytes and additives, which might ultimately impact battery performance. Our preliminary results make evident that small‐angle neutron scattering could be employed to better understand the complex microstructure solid electrolyte interphase formation and its accurate thickness, on a mesophase graphite anode. [ABSTRACT FROM AUTHOR]

Thermal behavior and solid electrolyte interphase (SEI) are crucial topics for the development and operation of the lithium-ion battery. To investigate the thermal behavior and SEI formation in a lithium-ion battery (C-LiMn 0.5 Ni 0.3 Co 0.2 O 2), a numerical method combining the pseudo-two-dimensional electrochemical model, heat transfer model, and capacity fading model is developed. For the battery operated at a low C-rate, the ohmic heat and the reversible heat dominate the heat generation at a low state of charge (SOC) and high SOC, respectively. Alternatively, the ohmic heat is the dominant factor causing heat generation at a high C-rate. The reversible heat reaches a maximum at the SOC of 65% due to the entropic coefficient of the cathode active materials. The SEI thickness increases around 70 nm with increasing the C rate cycling. The heat generation is the bottleneck for the resistance of Li+ ion conductivity at the SCI. The heat generation of the cathode is larger than that of the anode, which is caused by the low solid phase conductivity of the cathode. This analysis has provided useful insights into the thermal management of lithium-ion battery in the course of charging and discharging which is conducive to the development and safe operation of the battery. • A numerical method model is developed to investigate thermal behavior of a Li-ion battery. • Heat generation at a low C rate is mainly contributed by the reversible heat at high SOC. • Ohmic heat dominates heat generation at a high C rate. • Heat generation of the cathode is larger than that of the anode. • SEI thickness increases around 70 nm with increasing the C rate cycling. [ABSTRACT FROM AUTHOR]

The rapid rate of technology obsolescence in many high-technology markets makes it imperative for firms to renew their technological bases constantly. Given its critical importance, the technology acquisition from the fast followers’ perspective needs to be the subject of careful analysis. This paper aims to identify the factors influencing fast-follower firms’ choice of technology acquisition model, using a multi-factorial analysis and taking into account their technological capabilities, marketing capabilities, and environmental risk tradeoffs. This study sourced data from the Securities Data Company (SDC) Platinum Database for a total of 205 instances of technological cooperation between technology holders and fast followers in the LED industry. Based on the empirical results, some significant findings were found. First, regarding technological capabilities, when fast-follower firms had greater R&D, complementary manufacturing capabilities, and technological similarities with the partners, they preferred the acquisition model that required higher resource commitments. Secondly, when fast followers had marketing channel advantages, they were more likely to choose a high resource-commitment acquisition model to obtain time-to-market benefits. [ABSTRACT FROM PUBLISHER]

The core-food (CF) approach, first adopted in the United States in the 1980s, has been widely used by many countries to assess the exposure to dietary hazards at a population level. However, the reliability of exposure estimates (C × CR) depends critically on sampling methods designed for the detected chemical concentrations (C) of each CF to match with the corresponding consumption rate (CR) estimated from the surveyed intake data. In order to reduce the uncertainty of food matching, this study presents a sampling design scheme, namely the subsample method, for the 2016 Taiwan total diet study (TDS) on veterinary drugs. We first combined the four sets of national dietary recall data that covered the entire age strata (1–65+ years), and aggregated them into 307 CFs by their similarity in nutritional values, manufacturing and cooking methods. The 40 CFs pertinent to veterinary drug residues were selected for this study, and 16 subsamples for each CF were designed by weighing their quantities in CR, product brands, manufacturing, processing and cooking methods. The calculated food matching rates of each CF from this study were 84.3–97.3%, which were higher than those obtained from many previous studies using the representative food (RF) method (53.1–57.8%). The subsample method not only considers the variety of food processing and cooking methods, but also it provides better food matching and reduces the uncertainty of exposure assessment. [ABSTRACT FROM PUBLISHER]

Consumers with different lifestyles often have distinctive needs for the same type of technology products. Previous studies have focused mostly on the characteristics and pricing of these products but there is lack of a comprehensive study on the effect of internal demands from consumers and the sources of external information on intentions to purchase. This study proposes a hybrid decision-making model that integrates product characteristics, consumers’ internal demands and sources of external information for the exploration of behavioural patterns of consumers with different lifestyles when purchasing technology products. The empirical results suggest that lifestyle plays a significant role in moderating consumers’ purchase intentions. Among various consumers, early adopters’ purchase intention is motivated by features that highlight self-personality, while those of the pragmatists and the majority are mainly motivated by ease of contact, work need and sense of group. In addition, both the early adopters and the majority are influenced by the introduction of network and magazines, while the pragmatists are mainly affected by the introduction of retailers. [ABSTRACT FROM PUBLISHER]

In the currently rapidly changing business world, innovation has not only become the key to survival and success, but also the defining challenge of organisations. For latecomer firms, however, because of their inherent resource constraints, innovation has become a far more complex undertaking, similar to a multidimensional puzzle. Although there have been an increasing number of practitioner-based surveys, a discrepancy still remains between academia and industry concerning the role and importance of R&D in innovation. Therefore, this study carried out an industry–university–institution survey of Taiwan, based on a multidimensional framework of the innovation puzzle: human, R&D, flow and connection. The results reveal several interesting clues and provide a better understanding of the innovation puzzle for latecomers, and more importantly, resolves the puzzle that could help latecomers identify where new opportunities lie and what weaknesses they must strengthen. [ABSTRACT FROM AUTHOR]