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Compounds crystallizing in the structure of NaZr 2 (PO 4) 3 (NZP) are considered as promising materials for solid state electrolytes in Li-ion batteries. Using density functional theory (DFT), a systematic computational screening of 18 NZP compounds, namely, LiX 2 (LO 4) 3 with X = Ti , V, Fe, Zr, Nb, Ru, Hf, Ta, Os, and L = P , Mn, is performed with respect to their activation energies for vacancy-mediated Li migration. It is shown how the different ionic radii of the cationic substitutions influence structural characteristics such as the octahedron volumes around Li ions on the initial-state and transition-state sites, which affect the activation energies ("composition–structure–property" relationships). The prevalent assumption that structural bottlenecks formed by triangularly arranged oxygen atoms at a certain location along the migration path determine the energy barriers for Li migration is not supported by the DFT results. Instead, the ionic neighborhood of the migrating ion in the initial and in the transition state needs to be taken into account to relate the structure to the activation energies. This conclusion applies to Na-containing NZP compounds as well. [ABSTRACT FROM AUTHOR]

Abstract: In searching for polymer‐based electrolytes with improved performance for lithium ion and lithium metal batteries, we studied block copolymer electrolytes with high amounts of bis(trifluoromethane)sulfonimide lithium obtained by macromolecular co‐assembly of a poly(isoprene)‐block‐poly(styrene)‐block‐poly(ethylene oxide) and the salt from tetrahydrofuran. Particularly, an ultra‐short poly(ethylene oxide) block of 2100 g mol−1 was applied, giving rise to 2D continuous lamellar microstructures. The macroscopic stability was ensured with major blocks from poly(isoprene) and poly(styrene), which separated the ionic conductive PEO/salt lamellae. Thermal annealing led to high ionic conductivities of 1.4 mS cm−1 at 20 °C with low activation energy and a superior lithium ion transference number of 0.7, accompanied by an improved mechanical stability (storage modulus of up to 107 Pa). With high Li:O ratios >1, we show a viable concept to achieve fast Li+ transport in block copolymers (BCP), decoupled from slow polymer relaxation. [ABSTRACT FROM AUTHOR]

All-solid-state lithium-ion electrolytes offer substantial safety benefits compared to flammable liquid organic electrolytes. However, a great challenge in solid electrolyte batteries is forming a stable and ion conducting interface between the electrolyte and active material. This study investigates and characterizes a possible solid-state electrode-electrolyte pair for the high voltage active cathode material LiMn1.5Ni0.5O4 ( LMNO) and electrolyte Li1+ xAlxGe2-x( PO4)3 ( LAGP). In situ X-ray diffraction measurements were taken on pressed pellets comprised of a blend of LMNO and LAGP during exposure to elevated temperatures to determine the product materials that form at the interface of LMNO and LAGP and the temperatures at which they form. In particular, above 600°C a material consistent with LiMn PO4 was formed. Scanning electron microscopy and energy-dispersive X-ray spectroscopy were used to image the morphology and elemental compositions of product materials at the interface, and electrochemical characterization was performed on LMNO-coated LAGP electrolyte pellet half cells. Although the voltage of Li/ LAGP/ LMNO assembled batteries was promising, thick interfacial phases resulted in high electrochemical resistance, demonstrating the need for further understanding and control over material processing in the LAGP/ LMNO system to reduce interfacial resistance and improve electrochemical performance. [ABSTRACT FROM AUTHOR]

All-solid-state lithium-ion electrolytes offer substantial safety benefits compared to flammable liquid organic electrolytes. However, a great challenge in solid electrolyte batteries is forming a stable and ion conducting interface between the electrolyte and active material. This study investigates and characterizes a possible solid-state electrode-electrolyte pair for the high voltage active cathode material LiMn1.5Ni0.5O4 ( LMNO) and electrolyte Li1+ xAlxGe2-x( PO4)3 ( LAGP). In situ X-ray diffraction measurements were taken on pressed pellets comprised of a blend of LMNO and LAGP during exposure to elevated temperatures to determine the product materials that form at the interface of LMNO and LAGP and the temperatures at which they form. In particular, above 600°C a material consistent with LiMn PO4 was formed. Scanning electron microscopy and energy-dispersive X-ray spectroscopy were used to image the morphology and elemental compositions of product materials at the interface, and electrochemical characterization was performed on LMNO-coated LAGP electrolyte pellet half cells. Although the voltage of Li/ LAGP/ LMNO assembled batteries was promising, thick interfacial phases resulted in high electrochemical resistance, demonstrating the need for further understanding and control over material processing in the LAGP/ LMNO system to reduce interfacial resistance and improve electrochemical performance. [ABSTRACT FROM AUTHOR]

Sterile amino acid solutions are applied in medical care as part of Total Parenteral Nutrition systems. Typical formulations consist of variable admixtures of essential and non-essential amino acids together with carbohydrates, electrolytes, vitamins, trace element solutions and lipid emulsions. The complexity of these formulations gives rise to stability and compatibility reflections. This review focuses on amino acid stability in pure amino acid solution and name methods of assessment. Incompatibilities of amino acids with the other ingredients are matter of concern in clinical practice and evaluated for relevance. [ABSTRACT FROM AUTHOR]

Background: Despite exercising in cool environments, ice hockey players exhibit several dehydration risk factors. Individualized fluid plans (IFPs) are designed to mitigate dehydration by matching an individual's sweat loss in order to optimize physiological systems and performance. Methods: A randomized control trial was used to examine IFP versus ad libitum fluid ingestion on hydration in 11 male minor professional ice hockey players (mean age = 24.4 ± 2.6 years, height = 183.0 ± 4.6 cm, weight = 92.9 ± 7. 8 kg). Following baseline measures over 2 practices, participants were randomly assigned to either control (CON) or intervention (INT) for 10 additional practices. CON participants were provided water and/or carbohydrate electrolyte beverage to drink ad libitum. INT participants were instructed to consume water and an electrolyte-enhanced carbohydrate electrolyte beverage to match sweat and sodium losses. Urine specific gravity, urine color, and percent body mass change characterized hydration status. Total fluid consumed during practice was assessed. Results: INT consumed significantly more fluid than CON (1180.8 ± 579.0 ml vs. 788.6 ± 399.7 ml, p = 0.002). However, CON participants replaced only 25.4 ± 12.9% of their fluid needs and INT 35.8 ± 17.5%. Mean percent body mass loss was not significantly different between groups and overall indicated minimal dehydration (<1.2% loss). Pre-practice urine specific gravity indicated CON and INT began hypohydrated (mean = 1.024 ± 0.007 and 1.024 ± 0.006, respectively) and experienced dehydration during practice (post = 1.026 ± 0.006 and 1.027 ± 0.005, respectively, p < 0.001). Urine color increased pre- to post-practice for CON (5 ± 2 to 6 ± 1, p < 0.001) and INT (5 ± 1 to 6 ± 1, p < 0.001). Conclusions: Participants consistently reported to practice hypohydrated. Ad libitum fluid intake was not significantly different than IFP on hydration status. Based on urine measures, both methods were unsuccessful in preventing dehydration during practice, suggesting practice-only hydration is inadequate to maintain euhydration in this population when beginning hypohydrated. [ABSTRACT FROM AUTHOR]

In this study, we proposed a new real-time internal stress measurement design based on bending deformation of electroplated specimen. The volume change of fluid compartment caused by bending deformation of specimen on the wall was measured by fluid column height in a glass tube, and then the variation of internal stress could be calculated according to the Stoney formula. There are many factors that can cause variations during measurement, such as capillary action in glass tube, temperature of electrolyte, and clamped boundary condition of specimen. Their effects in measurement were taken into account and compensated accordingly. When tested in Watts bath for nickel plating, the proposed design successfully recorded the evolution of internal stress with respect to plating thickness. Comparing with the results from commercial bent strip method and the literature, the proposed design was capable of measuring both tensile and compressive internal stresses during electroplating with good precision. [ABSTRACT FROM AUTHOR]

The electrolyte is one of the most important components of the vanadium redox flow battery and its properties will affect cell performance and behavior in addition to the overall battery cost. Vanadium exists in several oxidation states with significantly different half-cell potentials that can produce practical cell voltages. It is thus possible to use the same element in both half-cells and thereby eliminate problems of cross-contamination inherent in all other flow battery chemistries. Electrolyte properties vary with supporting electrolyte composition, state-of-charge, and temperature and this will impact on the characteristics, behavior, and performance of the vanadium battery in practical applications. This Review provides a broad overview of the physical properties and characteristics of the vanadium battery electrolyte under different conditions, together with a description of some of the processing methods that have been developed to produce vanadium electrolytes for vanadium redox flow battery applications. [ABSTRACT FROM AUTHOR]

Beta-phase alloys like Ti-40Nb with outstanding elastic properties are promising new materials for implant applications. For the generation of bioactive surface states electrodeposition of hydroxyapatite (Hap) was conducted on alloy substrates in a water-based electrolyte with 6.1 × 10 − 4 M Ca(NO 3 ) 2 and 3.6 × 10 − 4 M NH 4 H 2 PO 4 and results were compared with those obtained for cp2-Ti. The impact of electrolyte temperature and of different chemical pre-treatments of the alloy surface, i.e. etching in piranha solution and alkali treatment, on the cyclic polarization behavior and on the potentiostaticly generated deposit characteristics were assessed. At all adjusted surface states the high Nb content of the beta-phase alloy alters passivity by incorporation of oxidized Nb species in the Ti oxide film, but this has no significant impact on the cathodic reduction steps of the complex deposition process. On Ti-40Nb single-phase microcrystalline Ca 10 (PO 4 ) 6 OH 2 (Hap) with preferred {002} orientation grows. Increasing the electrolyte temperature from 333 K to 353 K yields accelerated Hap growth rates and a morphology change from plate-like to needle-like. At 353 K on mechanically ground Ti-40Nb, adhesive layers with a mean thickness of 1–2 μm precipitate. Chemical pre-treatments of the alloy surface yield small variations of the Hap coating morphology. [ABSTRACT FROM AUTHOR]

The decline of garden rose sales over the past 20 years can be partially attributed to the lack of material adapted to a wide range of landscapes, which includes adaptation to high temperature stress.Currentmethods for evaluating high temperature susceptibility in garden roses are based on field observations, which are time consuming and subjected to ever-changing environmental conditions. A series of experiments were conducted to optimize protocols and compare the use of chlorophyll fluorescence (CFL) and cell membrane thermostability (MTS) by way of electrolyte leakage as methods to screen for high temperature susceptibility. Immature leaves proved better than mature leaves for both CFL and MTS measurements, using either detached leaf or whole plant stress assays. MTSmeasured on immature leaves stressed in a water bath at 50 °C for 45 minutes proved most consistent in separating rose clones based on high temperature susceptibility. Stressing actively growing plants with flower buds of 2 mm in diameter in a heat chamber at 44 °C for 3 hours resulted in increased flower abscission and leaf necrotic lesions on more susceptible clones when compared with those that were heat tolerant. Combining MTS measurements from immature leaves stressed in a water bath with the flower abscission and leaf necrosis responses 10 days after stress in a heat chamber could be the first step to screen and select against the more susceptible clones in a garden rose breeding program. Power analyses suggest that the proposed MTS protocol would be efficient in detecting differences between clones when the difference in electrolyte leakage is greater than 10%. [ABSTRACT FROM AUTHOR]

In the paper we propose the model that describes the interaction energy of the hydrated ions in uni-univalent electrolytes at various concentrations and temperatures. The approach developed allows one to calculate the main effect of various physical factors, and based on this, to determine the activity coefficients in the range of concentrations from zero to several mol/l and the range of temperatures from zero to several tens of degrees. The results of simulation have been tested by comparison with available literature data. [ABSTRACT FROM AUTHOR]

Low-order, explicit models of lithium ion cells are critical for real-time battery management system (BMS) applications. This paper presents a seventh-order, electrolyte enhanced single particle model (ESPM) with electrolyte diffusion and temperature dependent parameters (ESPM-T). The impedance transfer function coefficients are explicit in terms of the model parameters, simplifying the implementation of temperature dependence. The ESPM-T model is compared with a commercially available finite volume based model and results show accurate matching of pulse responses over a wide range of temperature (T) and C-rates (I). The voltage response to 30 s pulse charge-discharge current inputs is within 5% of the commercial code for 25°C < T < 50°C at I ≤ 12.5C and -- 10°C < T < 50°C at I ≤ IC for a graphite!nickel cobalt manganese (NCM) lithium ion cell. [ABSTRACT FROM AUTHOR]

A power-law expression is proposed for correlating the temperature dependence of infinite-dilution activity coefficients ( [ABSTRACT FROM AUTHOR]

Nanoporous anodic titanium dioxide (ATO) layers were formed via a three-step anodization process in glycerol-based electrolyte containing 0.38wt.% NH4F and 1.79wt.% H2O. The effects of applied potential (10-70V), duration of the third step of anodization (15, 30 and 60min) and the previous usage of the electrolyte on formation of ATO layers were examined at the anodizing temperature of 40°C. It was found that at 10V in both the fresh and used electrolytes, the porous layers are observed for short anodizing times and the compact oxide layers were formed when the time was extended to 60min. On the other hand, the uneven oxide layers were obtained at 70V. The structure and surface morphology analyses showed that for the fresh electrolyte the pore diameter increases with increasing anodizing potential and time. However, for the used electrolyte the pore diameter increases with potential and decreases or remains constant with time. The latter one is attributed to the enhanced precipitation of hydrous titanium dioxide on the ATO surface. The precipitation of hydrous titanium dioxide is also confirmed by oxide thickness analyses performed for the fresh and used electrolytes. The current density-time plots showed that usage of the previously used electrolyte leads to retardation of the oxide formation as a result of partial depletion of the fluoride ions from the electrolyte. These results were confirmed by measurements of the electrolyte conductance. The calculated efficiency of the anodization process, based on the thickness of the oxide layers, are significantly higher for the fresh electrolyte than for the used one. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ce1 − x Sr x O2 − δ (x =0.05–0.2) were synthesized by citrate-complexation method. [•] Pure solid solution was found for x =0.05 unlike other compositions. [•] Raman spectra confirms the existence SrCeO3 secondary phase for x >0.05. [•] Conductivity decreases with increase in x for Ce1 − x Sr x O2 − δ (x =0.05–0.2). [•] Sr-doped ceria here showed higher conductivity when compared to rare-earth doped ceria. [Copyright &y& Elsevier]

This paper presents the effect of some electrolytes on the Krafft temperature ( T) of cetylpyridinium chloride in aqueous solution. The results show that more chaotropic anions raise while less chaotropic anions lower the T of the surfactant. More chaotropic Br, SCN and I form contact ion pairs with the cetylpyridinium ion and reduce the electrostatic repulsion between the surfactant molecules. As a result, these ions exhibit salting-out behavior, showing an increase in the T of the surfactant. On the other hand, less chaotropic NO increase the solubility of the surfactant, with a consequent decrease in the T. Surface tension data of the salt solutions reveal that more chaotropic ions show a relatively less molar increase in surface tension compared to less chaotropic ions. This indicates that less chaotropic ions have a preferential tendency to be negatively adsorbed at the air-water interface as well as hydrocarbon-water interface and thereby disturb the hydration of the surfactant. SO being a strong kosmotrope cannot form contact ion pairs with the cationic part of the surfactant. Rather this ion preferentially remains in the bulk because of its strong tendency for hydration and thereby stays apart. As a result, SO also causes a significant lowering of the T of the surfactant. Thus it appears that contrary to the usual trend SO behave like a chaotrope showing salting-in effect of the surfactant. [ABSTRACT FROM AUTHOR]

Lithium ion batteries (LIBs) are key components for portable electronic devices that are used around the world. However, thermal decomposition products in the battery reduce its lifetime, and decomposition processes are still not understood. In this study, a rapid method for in situ analysis and reaction monitoring in LIB electrolytes is presented based on high-resolution mass spectrometry (HR-MS) with low-temperature plasma probe (LTP) ambient desorption/ionization for the first time. This proof-of-principle study demonstrates the capabilities of ambient mass spectrometry in battery research. LTP-HR-MS is ideally suited for qualitative analysis in the ambient environment because it allows direct sample analysis independent of the sample size, geometry, and structure. Further, it is environmental friendly because it eliminates the need of organic solvents that are typically used in separation techniques coupled to mass spectrometry. Accurate mass measurements were used to identify the time-/condition-dependent formation of electrolyte decomposition compounds. A LIB model electrolyte containing ethylene carbonate and dimethyl carbonate was analyzed before and after controlled thermal stress and over the course of several weeks. Major decomposition products identified include difluorophosphoric acid, monofluorophosphoric acid methyl ester, monofluorophosphoric acid dimethyl ester, and hexafluorophosphate. Solvents (i.e., dimethyl carbonate) were partly consumed via an esterification pathway. LTP-HR-MS is considered to be an attractive method for fundamental LIB studies. [ABSTRACT FROM AUTHOR]

Abstract: The behavior of sulfonated poly (ether ether ketone) (SPEEK) with different degrees of sulfonation (DS) (60–76%) blended with charged surface modifying macromolecule (cSMM) at different operating temperatures as an electrolyte membrane for direct methanol fuel cell (DMFC) application has been studied. A good DMFC electrolyte membrane should possess high proton conductivity and low methanol permeability. In this work, the fabricated SPEEK/cSMM membranes were compared with pure SPEEK and commercial Nafion 112 membranes in terms of water uptake, proton conductivity, and methanol permeability at temperature range of room to 80°C. The water uptake of SPEEK/cSMM membranes increased with the temperature and it was higher than that of SPEEK and Nafion 112 membranes; however newly fabricated membranes with 68% and 76% DS were dissolved at high temperatures although showed the same trend at lower temperatures. In agreement with the result of water uptake, proton conductivity of SPEEK/cSMM membranes also increased with temperature and was higher as compared to the corresponding SPEEK membranes; however it was still lower than that of Nafion 112. The methanol permeability values of the SPEEK/cSMM membranes were lower at different temperatures as compared to corresponding SPEEK and Nafion 112 at the same condition. Owing to considerable proton conductivity and lower methanol permeability values, SPEEK60/cSMM exhibited the highest overall performance than other tested membranes at 60°C. These results indicated that SPEEK60/cSMM membrane is promising to be used as a polymer electrolyte membrane in direct methanol fuel cell. [Copyright &y& Elsevier]

Abstract: Chloride attack is a serious deterioration mechanism of reinforced concrete structures, causing steel corrosion in concrete. As a repair method, the electrochemical chloride removal technique named desalination was developed and has been applied to many concrete structures. Desalination can extract chloride ions (Cl−) from hardened concrete but it is impossible to remove all Cl− contained in concrete. Therefore, it is important to improve chloride removal efficiency in order to help prevent early deterioration of concrete after desalination. In this study, the influence of the temperature of the electrolyte solution on electrochemical chloride removal efficiency is investigated by chemical analysis to evaluate electrochemical migration of several kinds of ions. As a result, it was found that chloride removal percentage and transference number of Cl− increased by about 10% with a rise of temperature ranging from 20°C to 40°C. [Copyright &y& Elsevier]

This study was focused on the performances of membrane electrode assemblies (MEAs) consisting of the proton-conducting 90PVA/3PWA/4GPTMS/1PO/2Gl and 80PVA/10PWA/6GPTMS/2PO/2Gl hybrid membranes as electrolytes together with a Pt/C electrode for proton exchange membrane fuel cells. The MEAs were fabricated and tested as a function of temperature and humidity, and yielded a current density value of about 350 mA cm at 60 °C and 100% relative humidity (RH) for the membrane electrolyte 80PVA/10PWA/6GPTMS/2PO/2Gl. These values were compared with Nafion® membranes, and the single-cell performances based on proton-conducting organic/inorganic hybrid electrolytes were discussed. The test conditions employed were equivalent for each MEA that had an active area of 5 cm. These hybrid membranes showed a high proton conductivity in the range of 10-10 S cm at low temperatures, i.e., 60, 80, and 90 °C, and 50%, 75%, and 100% RH. [ABSTRACT FROM AUTHOR]

The article presents information on a new liquefied-gas-based electrolyte developed by researcher Cyrus Rustomji and colleagues that enables lithium batteries to operate efficiently at very cold temperatures. It is reported that the electrolyte can be useful for electric cars that travel much farther distances in cold climates than they can with today’s batteries.