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Effective interventions are needed to help adolescents with T1D develop independent self-management skills to prevent commonly observed deterioration of disease self-management resulting in poor health outcomes. Using a prospective RCT design, we assessed the impact of a nurse-led education program based on motivational interviewing (MI) in youth with Type 1 diabetes (T1D).After parental consent and youth assent, we prospectively randomized 66 adolescents 13-18 years old with T1D to either usual care (every 3 months visit with pediatric endocrinologist) or usual care supplemented by 2 in-person and 4 follow-up phone calls with a nurse educator in a pediatric endocrinology clinic of the University Hospital Farhat Hached, Sousse, Tunisia. We used MI sessions to support youth general and disease specific self-management skills. Outcomes were change, between baseline and 6 months, in TRAQ (a validated measure of youth self-management) scores and HbA1c values.Mean TRAQ scores (based on a 5-point Likert scale) increased by 1.44 points (s.d. = 0.56) in the Intervention Group versus 0.26 points (s.d. = 0.34) in the control group (p0.001). The mean HbA1C value decreased in the intervention group by 0.95 units versus a decrease of 0.12 units in the control group (p = 0.047).We found that a brief, nurse-led MI-based educational intervention, integrated into specialty pediatric care, resulted in a significant improvement in both self-reported self-management skills and in HbA1c values.Registered in ClinicalTrials.gov Identifier: NCT04798937.

Roll-to-roll (R2R) slot-die coating of polymer electrolyte membrane fuel cell (PEMFC) catalyst layers represents a scalable deposition method for producing 10-20 m2·min-1 of catalyst-coated gas diffusion layers (GDLs). This high-throughput production technique will help lower the cost of PEMFC catalyst layers. The uniformity of the wet layer applied by slot die deposition is affected by process parameters such as substrate speed, vacuum pressure applied at the upstream meniscus, gap between the slot die lips and substrate, ink rheology, and other ink and substrate properties. The set of conditions for producing a defect-free coating with a dilute ink typically requires little to no upstream vacuum pressure, so suitable operating conditions can be found easily through trial and error and operator intuition. However, the higher viscosity of more concentrated inks dramatically shifts the range of settings that result in a homogeneous coating to higher vacuum levels, which are harder to find through hit or miss. A predictive model showing the range of operable conditions decreases material wastage inherent in experimentally searching for suitable parameters. In this study, the defect-free coating parameter window is explored experimentally and theoretically for two concentrations of PEFC cathode inks. Both a full capillary hydrodynamic model and a computationally cheaper viscocapillary model successfully predict the experimentally determined coating window within the experimental and model uncertainty limits for inks with 5.3 wt.% and 12.0 wt.% solids ink while maintaining the 0.1 mgPt·cm-2 Pt areal loading target. This paper demonstrates a viable pathway for meeting the $30/kWnet ultimate cost target of the United States Department of Energy (U.S. DOE) Hydrogen Fuel Cells Technologies Office (HFTO). The concentrated ink lowers the thermal energy and capital expenditure (CapEx) budget of the coating process by decreasing the amount of time, energy, and floorspace required for drying the coating.

Here we report dual ion conduction capability of Na-based NASICON type super ion conductor materials using Na1+xMnx/2Zr2–x/2(PO4)3 (NMZP) as a candidate system. This method enables the use of Na-ba...

Lithium-ion battery (LIB) production can benefit both economically and environmentally from aqueous processing. Although these electrodes have the potential to surpass electrodes conventionally processed with N-methyl-2-pyrrolidone (NMP) in terms of performance, significant issues still exist with respect to ultra-thick cathodes (≫4 mAh/cm2 areal capacities). A major concern for these types of electrodes with high-nickel active material stems from lithium leaching from active material, which drives the pH of the dispersion in excess of 12 and subsequently corrodes the current collector interface. As this corrosion reaction proceeds, hydrogen generation at the interface creates bubbles which cause severe cracking in the dried electrode surface. When areal loadings are increased, this effect becomes more pronounced and is detrimental to both mechanical and electrochemical properties of these electrodes. Herein, a technique for mitigating corrosion at the current collector by adjusting the pH of the dispersion with the addition of phosphoric acid is investigated. Phosphoric acid was added in 0.5 wt% increments between 0.0 and 1.5 wt%, and effects on rheology, adhesion, corrosion, and electrochemical performance were investigated. A technique is reported for producing aqueous processed cathodes with areal loadings of 6–8 mAh/cm2 with reduced surface cracking and superior high-rate discharge capacity (i.e. high-power performance) for this class of cathode loadings.

Fresh-cut mango (Mangifera indica) slices and chunks garner an exotic image and are highly appreciated for their unique flavor and nutritional value. However, processors tend to use firm unripe mangoes to achieve shelf life of 10 to 14 days, which compromises eating quality. The post-processing life of ripe fresh-cut mangoes is limited by tissue softening, translucency, and browning. The current study was undertaken to investigate whether edible coatings can extend the shelf life of fresh-cut mangoes processed at an eating-ripe stage. Three edible coatings, carboxymethylcellulose (1% w/v), aloe (Aloe vera) powder (2% w/v), and whey protein isolate (2% w/v), supplemented with calcium ascorbate 2% w/v (firming agent) and the antioxidants citric acid (0.8% w/v) and acetyl-N-cysteine (0.4% w/v), were used. The mixture of antibrowning agents, whether applied alone or with the edible coatings, was the most effective at reducing slice browning up to 10 and 11 days at 5 °C for ‘Tommy Atkins’ and ‘Kent’, respectively. In general, there were no differences in firmness and flavor among the three edible coatings. Calcium ascorbate alone did not suppress browning consistently, whereas citric acid appeared to be the ingredient having the greatest antibrowning effect on slice quality. Citric acid can easily be used by processors of fresh-cut mangoes to prevent browning.

Garnet oxides are a promising material family for solid-state batteries (SSBs). Dendrite formation in solid electrolytes critically limits the applicability of SSBs because of limiting Coulombic ef...

Objective Project ECHO (Extension for Community Healthcare Outcomes), a telementoring program, utilizes lectures, case‐based learning, and an “all teach–all learn” approach to increase primary care provider (PCP) knowledge/confidence in managing chronic health conditions. The American Academy of Pediatrics (AAP) Epilepsy and Comorbidities ECHO incorporated quality improvement (QI) methodology to create meaningful practice change, while increasing PCP knowledge/self‐efficacy in epilepsy management using the ECHO model. Methods Monthly ECHO sessions (May 2018 to December 2018) included lectures, case presentations/discussion, and QI review. Pediatric practices were recruited through the AAP. Practices engaged in ECHO sessions and improvement activities including monthly Plan‐Do‐Study‐Act cycles, team huddles, chart reviews, and QI coaching calls to facilitate practice change. They were provided resource toolkits with documentation templates, safety handouts, and medication side effects sheets. QI measures were selected from the American Academy of Neurology Measurement Set for Epilepsy. The AAP Quality Improvement Data Aggregator was used for data entry, run chart development, and tracking outcomes. Participants completed retrospective surveys to assess changes in knowledge and self‐efficacy. Results Seven practices participated across five states. Average session attendance was 14 health professionals (range = 13‐17). A total of 479 chart reviews demonstrated improvement in six of seven measures: health care transition (45.3%, P = .005), safety education (41.6%, P = .036), mental/behavioral health screening (32.2% P = .027), tertiary center referral (26.7%, not significant [n.s.]), antiseizure therapy side effects (23%, n.s.), and documenting seizure frequency (7.1%, n.s.); counseling for women of childbearing age decreased by 7.8%. Significance This project demonstrated that integrating QI into an ECHO model results in practice change and increases PCP knowledge/confidence/self‐efficacy in managing epilepsy.

As lithium-ion battery (LIB) active material and cell manufacturing costs continue to drop with wider adoption of electric vehicles, electrode and cell processing costs remain too high in terms of reaching the ultimate U.S. Department of Energy (DOE) cell cost target of $80/kWh. This paper primarily covers major materials chemistry advancements made over the last 10 ​years ​at Oak Ridge National Laboratory (ORNL) in the space of advanced manufacturing science for LIBs with the aim of simultaneously meeting the ultimate cost target, 500 ​Wh/kg gravimetric energy density, 10-15-min fast charge times, and 1000 deep discharge cycles. Aqueous electrode processing with a variety of active anode and cathode materials is now a standard procedure at the DOE Battery Manufacturing R&D Facility at ORNL (BMF), including the latest processes developed for Ni-rich cathodes. New results on cobalt-free LiNi0.8Fe0.1Al0.1O2 (NFA 811) are also included and discussed in an electrode processing advantage context. In addition, colloidal processing advancements have been made for Si/C composite anodes for achieving >600 ​mA ​h/g capacities. Optimization of electrode coating parameters and drying protocols have been completed, which has elucidated how key processing variables need to be changed when parameters such as slurry solids loading, solvent type, and wet electrode thickness are changed. ORNL has also increased the line speeds at which thick cathodes can be processed using ultra-fast electron beam (EB) curing and substantially decreased formation cycling times to

Thermal stability is a crucial parameter that must be considered within the overall performance metrics of Ni-rich layered oxide cathodes. While the intrinsic structural stability of the cathode ma...

An engaging area of research in sodium-ion batteries (SIBs) has been focusing on discovery, design, and synthesis of high-capacity cathode materials in order to boost energy density to levels close enough to that of state-of-the-art lithium-ion batteries. Of particular interest, P2-type layered oxide, Na2/3Fe1/2Mn1/2O2, has been researched as a potential cathode in SIBs based on its high theoretical capacity of 260 mA h/g and use of noncritical materials. However, the reported synthesis methods are not only complex and energy-demanding but also often yield inhomogeneous and impure materials with capacities less than 200 mA h/g under impractical test conditions. Here, we report a novel synthesis route using low-temperature eutectic reaction to produce highly homogeneous, crystalline, and impurity-free P2-NaxFe1/2Mn1/2O2 with enhanced Na-ion diffusivity and kinetics. The overall electrochemical performances of the Na-ion cells have been improved by pairing the P2-cathode with presodiated hard carbon anodes, leading to reversible capacities in the range of 180 mA h/g. This new approach is a contribution toward the simplification of synthesis and scalability of sodium-based cathodes with high crystallinity and fine-tuned morphology and the realization of a sodium-ion battery system with lower cost and improved electrochemical performance.

To examine associations between in utero marijuana exposure and birth outcomes. In two separate cohorts (Appalachian, Rocky Mountain), data were collected from medical records. Marijuana exposure was positive based on urine drug screening at delivery, with nonexposed controls matched on multiple factors including other substance exposure. Marijuana-exposed newborns (n = 531) had significantly worse birth outcomes than controls (n = 531), weighing 218 g less, 82%, 79%, and 43% more likely to be low birth weight, preterm, or admitted to the NICU, respectively, and significantly lower Apgar scores. Marijuana exposure in utero predicted newborn factors linked to longer-term health and development issues. Effects were not attributable to other comorbidities in this study due to rigorous matching and biochemical verification of marijuana and other drug use. Findings add to growing evidence linking marijuana exposure to adverse birth and longer-term outcomes. Women should be encouraged to avoid marijuana use during pregnancy.

Replacing N-methyl-2-pyrrolidone (NMP) with water for processing of lithium-ion battery (LIB) electrodes has both cost and environmental benefits, which include reduced drying time, lower dryer cap...

Research on in utero opioid exposure impacts has focused on Neonatal Opioid Withdrawal Syndrome (NOWS). However, possible impacts on fetal growth and newborn wellbeing have emerged, with inconsistencies likely driven by methodological issues. Our goal was to compare birth outcomes between newborns with prenatal opioid exposure and a matched control group.Participants were identifiedCompared to biochemically verified controls, exposed newborns had higher rates of fetal growth restriction, weighed less, had decreased length and head circumference, and had higher rates of respiratory distress, sepsis, and jaundice. No significant differences in gestational length, Apgar scores, or neonatal hypoglycemia were found. Adjusted regression analyses revealed that compared to controls, those exposed had an average 150 g decrease in birth weight, a two-fold increased risk for IUGR (OR = 2.09), a nearly three-fold (OR = 2.80) increased risk for jaundice, a more than seven-fold (OR = 7.40) increased risk for respiratory distress, and a thirty-fold (OR = 30.47) increased risk for sepsis.Results suggest significant pregnancy and newborn outcomes beyond NOWS following pregnancy opioid use, informing clinical screening and treatment decisions to enhance health and wellbeing in pregnancy, during the neonatal period, and beyond.

The prevalence of opioid use disorder has increased across the United States, but the rural population of Appalachia has been disproportionately impacted. Concurrently, the slow, but steady progress in the legalization of marijuana may be affecting perception of marijuana use in pregnancy. However, marijuana use in pregnancy has been associated with adverse perinatal outcomes. Concomitant use of opioids and marijuana in pregnancy has not been evaluated.The primary aim of the study was to evaluate the association between confirmed marijuana use in late pregnancy and preterm birth in opioid-exposed pregnancies.A retrospective chart review was conducted that included all births from July 2011 to June 2016 from 6 delivery hospitals in South-Central Appalachia. Out of 18,732 births, 2368 singleton pregnancies indicated opioid use and met remaining inclusion criteria, with 108 of these mothers testing positive for marijuana at delivery. Independent sampleNeonates born to marijuana-positive women in opioid-exposed pregnancy were more likely to be born preterm, small for gestational age, have low birth weight, and be admitted to NICU. After statistically controlling for parity, marital status, tobacco and benzodiazepine use, preterm birth and low birth weight remained statistically significant with aOR of 2.35 (1.30-4.24) and 2.01 (1.18-3.44), respectively.Maternal use of marijuana in any opioid-exposed pregnancy may increase risk of preterm birth and low-birth weight infants. Prospective studies need to examine the dose and timing of marijuana and opioid use in pregnancy to better delineate perinatal effects. Nonetheless, pregnant women using opioids, including recommended medication assisted treatment for opioid use disorder, should be educated about the risks of concurrent marijuana use during pregnancy and may need to be counseled to abstain from marijuana use during pregnancy for an optimal outcome.

Cobalt content in Li-ion battery cathodes has become a top concern due to its price volatility and limited source availability. Low-cobalt, Ni-rich active materials are promising candidates for next-generation cathodes due to their high capacities, and water-based processing of these materials can further reduce both cost and environmental impact. We systematically evaluated the water compatibility of four different LiNixMn1-x-yCoyO2 (NMC) powders with increasing nickel contents. Comprehensive characterization verified there is no major change to their bulk structures, and only slight surface modifications related to the removal of contaminant species. For the first time, we demonstrate that LiNi0.8Mn0.1Co0.1O2 (NMC 811) cathodes can be formulated in water and cycled 1000 times in full pouch cells with excellent capacity retention (~70% compared to ~76% for NMP-processed cells). When implemented in future battery production lines, aqueous processing of Ni-rich NMC will simultaneously enable cost reductions and higher cell energy densities.

A layered oxide cathode, LiNi0.6Mn0.2Co0.2O2, undergoes noticeable crystal expansion by losing significantly higher amounts of Li+ at the end of fast charging cycles. However, the bulk structure of the cycled NMC622 is restored back to its pristine discharged state when intercalated with enough lithium ions during an electrochemical process.

This review will focus on a systems medicine approach to neonatal abstinence syndrome (NAS). Systems medicine utilizes information gained from the application of "omics" technology and bioinformatics (1). The omic approaches we will emphasize include genomics, epigenomics, proteomics, and metabolomics. The goals of systems medicine are to provide clinically relevant and objective insights into disease diagnosis, prognosis, and stratification as well as pharmacological strategies and evidence-based individualized clinical guidance. Despite the increasing incidence of NAS and its societal and economic costs, there has been only a very modest emphasis on utilizing a systems medicine approach, and this has been primarily in the areas of genomics and epigenomics. As detailed below, proteomics and metabolomics hold great promise in advancing our knowledge of NAS and its treatment. Metabolomics, in particular, can provide a quantitative assessment of the exposome, which is a comprehensive picture of both internal and external environmental factors affecting health.

PURPOSE The purpose of this study is to report preliminary evidence to support a new condition-specific measure of transition readiness that is theoretically grounded in the Stages of Changes framework. The Transition Readiness Assessment Questionnaire-Spina Bifida (TRAQ-SB) supplement is a newly developed tool used to measure independence and skill acquisition related to spina bifida. Similar to the Transition Readiness Assessment Questionnaire (TRAQ), the TRAQ-SB uses a 5-point Likert response set. METHODS Working with a multi-disciplinary team with expertise in the care of children with spina bifida, the authors developed twelve items pertaining to main aspects of SB self-management. The items were reviewed and revised through several iterations by the team and patients. The items were then fielded at a spina bifida Specialty Clinic, where 93 consecutive patients 12-25 years of age were approached to participate and 90 were administered the 20-item TRAQ and a 12-item TRAQ-SB questionnaire. A principal component analysis (PCA) was conducted on the twelve items with oblique rotation (promax). Criterion validity was also assessed by examining the correlation of the TRAQ-SB supplement with the TRAQ and with age. RESULTS Results of the factor analysis revealed that eleven of the twelve items loaded onto one factor with factor loadings ranging from 0.46 to 0.84. The scale yielded excellent internal reliability with a Cronbach alpha of 0.90. Correlations of the TRAQ-SB supplement scale score with the TRAQ overall scale score demonstrated good criterion validity (r= 0.74, p< 0.01). In addition, it was highly correlated with the TRAQ subscales, varying from 0.68 to 0.74 (all p< 0.01). Lastly, the TRAQ-SB was significantly correlated with age (r= 0.25, p< 0.01). CONCLUSIONS Results of our analyses indicated that the TRAQ-SB demonstrated good internal reliability and criterion validity as evidenced by strong correlation with age and the validated TRAQ measure. The TRAQ-SB tool can be useful to incorporate transition readiness assessment and self-management training into routine care for adolescents with spina bifida.

David Wood is a Senior Staff Scientist and University of Tennessee Bredesen Center Adjunct Faculty Member at Oak Ridge National Laboratory (ORNL), researching novel electrode architectures, mass transport phenomena, solid-liquid surface chemistry, advanced processing methods, manufacturing science, and materials characterization for low-temperature fuel cells, PEM electrolyzers, and lithium-ion batteries, and has been employed there since 2009. He is also the former ORNL Fuel Cell Technologies Program Manager (2011–2018), the former Roll-to-Roll Manufacturing Team and Group Leader (2015–2017), and a well-known energy conversion and storage researcher with an industrial and academic career that began in 1995. From 1997 to 2002, he was employed by General Motors Corporation and SGL Carbon Group, excelling at applied R&D related to automotive and stationary PEFC technology. Later work (2003–2009) at Los Alamos National Laboratory (LANL) and Cabot Corporation focused on elucidation of key chemical degradation mechanisms, development of accelerated testing methods, and component development. Dr. Wood received his BS in Chemical Engineering from North Carolina State University in 1994, his MS in Chemical Engineering from the University of Kansas in 1998, and his PhD in Electrochemical Engineering from the University of New Mexico in 2007. He was part of two LANL research teams that won the DOE Hydrogen Program R&D Award for outstanding achievement in 2005 and 2009. He was also part of the Cabot Corporation Direct Methanol Fuel Cell team, which won the Samuel W. Bodman Award for Excellence in 2008. Dr. Wood was also the 2011 winner of the ORNL Early Career Award for Engineering Accomplishment and led a team that won both a 2013 R&D 100 award and 2014 Federal Laboratory Consortium (FLC) award with Porous Power Technologies. He has received 19 patents and patent applications, authored 93 refereed journal articles and transactions papers, and authored 2 book chapters. Jianlin Li is a R&D Staff and University of Tennessee Bredesen Center Adjunct Faculty Member at Oak Ridge National Laboratory (ORNL). His research interest lies in materials synthesis, processing and characterization, electrode engineering, and manufacturing for energy storage and conversion. Dr. Li received his BS in Materials Chemistry and his MS in Materials Science from University of Science and Technology of China in 2001 and 2004, respectively, and his PhD in Materials Science and Engineering from the University of Florida in 2009. He is a recipient of several prestigious awards including two R&D 100 awards and one Federal Laboratory Consortium (FLC) award. He has received 14 patents and patent applications and authored 96 refereed journal articles and 3 book chapters. Seong Jin An is a Principal Engineer at Samsung Electronics leading rechargeable battery platforms for smartphone applications and has been employed there since late 2017. He had researched solid electrolyte interphase (SEI) in the lithium-ion battery as a guest at Oak Ridge National Laboratory (ORNL) (2014–2017). He worked at Samsung SDI in South Korea as a senior engineer developing PEM fuel cell stacks (2003–2011) and GS Fuel Cell in South Korea developing fuel processors for PEM fuel cell systems (2001–2003). He received his BS in Chemical Engineering from Seoul National University of Science and Technology in 1999, his MS in Chemical Engineering from Yonsei University, Seoul in 2001, his MS in Mechanical Engineering from Carnegie Mellon University, Pittsburgh in 2014, and his PhD in Energy Science & Engineering from University of Tennessee, Knoxville in 2017. He studied PEM fuel cells and lithium-ion batteries with fellowships during his MS and PhD programs. He has received over 200 patents and authored 21 refereed journal articles and transactions papers.

Electron beam curing is demonstrated as a promising method for high speed, low cost and environmentally friendly battery electrode manufacturing. This work reports transfer of this process to pilot scale equipment and evaluation of electrochemical performance in prototype 1.5 Ah pouch cells. Thick LiNi0.5Mn0.3Co0.2O2 (NMC532) composite electrodes with an areal loading of 25 mg cm−2 (∼4 mAh cm−2) are successfully cured at a line speed of 500 feet per minute at 275 keV. Compared to the NMC532 cathode processed via a conventional coating method, the electron beam cured electrodes show higher capacity fade in the first 100 cycles, but similar fade rate afterwards. Further improvement strategies are proposed and discussed. This work demonstrates that electron beam curing is a promising method for manufacturing thick battery electrodes at high speeds and low capital/operation cost. Keywords: Electron beam curing, Li-ion batteries, Thick electrode

Small pouch cells containing Si/graphite electrodes were systematically charged to 100, 120, 140, 160, 180 and 250% state of charge. Characterization of the Si/graphite electrode after the overcharge showed some features similar to those found in a pure graphite electrode. Since the amount of silicon in the electrode was ∼15 wt%, this was not unexpected. The effect of silicon was seen in the composition of the SEI layer and the trends in two components of the SEI layer.

Unlike conventional electrode processing for Li-ion batteries, which uses the expensive and highly toxic organic N-methyl-2-pyrrolidone (NMP) solvent, aqueous processing simply employs deionized wa...

Enabling fast charging capability of high energy density Li-ion cells could dramatically increase the widespread adoption of battery electric vehicles. However, fast charging is limited by Li ion depletion in the electrolyte and increasing Li ion transport from cathode to anode is essential. By evaluating different Li salts in the electrolyte, we find lithium bis(fluorosulfonyl)imide (LFSI) has both higher conductivity and higher Li ion transference number compared to the traditional LiPF6 salt. In a 12-minute charge, the electrolyte with LiPF6 salt reaches the cut-off voltage rapidly while the one with LiFSI exhibits a longer constant current charge with more capacity achieved. The LiFSI electrolyte also shows better cycling performance and less Li plating after repeated fast charging cycles. Keywords: Fast charging, NMC811, Electrolyte, LiFSI

A quantitative measurement of wettability between the porous electrode and the electrolyte in lithium-ion batteries can greatly improve our understanding of wetting behavior. Although the wetting balance method is widely used to measure the electrolyte transport rate in the porous electrodes, it suffers from several drawbacks and has limited accuracy. We here presented a combined experimental and theoretical investigation of the dynamics of electrolyte imbibition through electrodes. We proposed a novel method to accurately measure the electrolyte imbibition rate. Excellent agreement between the experimental data and the developed analytical model is obtained. The coefficient of penetrance (COP) and the solid permeability coefficient (SPC) are identified as important parameters, i.e., the electrolyte with higher COP value wets faster into an electrode, whereas for an electrolyte, the electrode with higher SPC value is more amenable to be impregnated. The effect of electrolyte salt concentration and electrolyte solvent has been studied in detail. The result suggests that increasing salt concentration adversely influences electrolyte wetting rate, whereas switching from EC-DEC system to EC-EMC system improves electrolyte wetting rate. In addition, for the electrolytes tested in this study, the imbibition into the uncalendered graphite anode is much faster than that into the uncalendered NMC532 cathode.

The mechanical and thermal conductivity properties of two composite elastomers were studied. Styrene&ndash, butadiene rubber (SBR) filled with functionalized graphene oxide (GO) and silica nanofibers, and styrene&ndash, butadiene&ndash, styrene (SBS) block copolymers filled with graphene oxide. For the SBR composites, GO fillers with two different surface functionalities were synthesized (cysteamine and dodecylamine) and dispersed in the SBR using mechanical and liquid mixing techniques. The hydrophilic cysteamine-based GO fillers were dispersed in the SBR by mechanical mixing, whereas the hydrophobic dodecylamine-based GO fillers were dispersed in the SBR by liquid mixing. Silica nanofibers (SnFs) were fabricated by electrospinning a sol&ndash, gel precursor solution. The surface chemistry of the functionalized fillers was studied in detail. The properties of the composites and the synergistic improvements between the GO and SnFs are presented. For the SBS composites, GO fillers were dispersed in the SBS elastomer at several weight percent loadings using liquid mixing. Characterization of the filler material and the composite elastomers was performed using x-ray photoelectron spectroscopy, x-ray diffraction, transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis, dynamic mechanical analysis, tensile testing, nanoindentation, thermal conductivity and abrasion testing.

Monterey pine is widely planted throughout low-elevation urban areas throughout California and is the most planted conifer in the San Francisco Bay Area. This pine, along with ponderosa and sugar pine, are subject to attack by red turpentine beetles; leaving them vulnerable to premature death and fire.Learn how to inspect and manage your pines to protect them from infestation by this beetle and three other beetles frequently found in dying urban conifers.

Recent achievements in high-energy batteries have been made by using Ni-rich NMC cathodes (LiNixMnyCo1–x–yO 2with x > 0.5) in conjunction with higher cell voltages. However, these gains have come at a cost of fast capacity fade and poor rate performace. In our previous study, we showed that Al2O3 ALD coatings on LiNi0.8Mn0.1Co0.1O2 (NMC811) and LiNi0.8Co0.15Al0.05O2 (NCA) cathodes prevented surface phase transitions, reduced impedance, and extended cycle life in high voltage cells. Here, neutron diffraction (ND), X-ray photoelectron spectroscopy (XPS), and electron energy loss spectroscopy (EELS) are used to fully investigate the mechanism by which ALD surface coatings mitigate NMC811 cathode degredation. Refinement of ND patterns indicated no changes in the bulk crystal structure of cycled cathodes with or without the Al2O3 coating. Rather, the improved performance of ALD-coated cathodes is clearly due to surface stabilization. EELS established that all three transition metal oxidation states were reduce...

Water-based processing for lithium-ion battery electrodes is attractive due to its lower manufacturing cost and smaller environmental impact. However, multiple challenges associated with aqueous cathode processing have hindered commercial adoption. Polymer binders are an important component of the electrode, and thus the choice of binders can alter electrode cycling performance significantly. In this work, four different water-based binder combinations are investigated for Ni-rich LiNi0.8Mn0.1Co0.1O2 (NMC811)-based cathodes, with a focus on the long-term electrochemical performance in practical-format full pouch cells. No additional pH-modulating additives were added to the aqueous cathode slurries, and no protective coatings were present on the cathode or aluminum current collector. Results are compared with the standard PVDF/NMP-based binder/solvent combination, used as a baseline. The influence of water-based binder type on slurry rheology and electrode microstructure are also discussed. All cells made by water-processing had worse rate performance compared to the baseline. However, the cell discharge capacity after 1000 U.S. Advanced Battery Consortium (USABC) cycles at C/3 charge/discharge rate was comparable to the baseline for two of the water-based cathode formulations (CMC & JSR, and LiPAA), demonstrating the potential viability of aqueous-processed Ni-rich cathodes at a commercial scale.

Most lithium-ion batteries still rely on intercalation-type graphite materials for anodes, and the formation process for them typically takes several days or even more to provide a stable solid electrolyte interphase (SEI). The slow formation step results in lower LIB production rates, requires a large number of battery cyclers, and constitutes the second highest cost during battery manufacturing. In an effort to decrease the high manufacturing cost associated with long formation times, we studied five different formation protocols in nickel-rich LiNi0.8Mn0.1Co0.1O2 (NMC811)/graphite cells where the total formation time varied from 10 to 86 h. Electrochemical characterization and post mortem analysis show that very long formation time do not necessarily improve long-term performance while very short formation protocols result in lithium plating and poorer electrochemical performance. We find the optimum formation cycling protocol is intermediate in length to minimize impedance growth, improve capacity retention, and avoid lithium plating.

Cells based on NMC/graphite, containing poly(vinylidene difluoride) (PVDF) binders in the positive and negative electrodes, were systematically overcharged to 100, 120, 140, 160, 180, and 250% state-of-charge (SOC). At 250% SOC the cell vented. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) of the anodes showed several state-of-overcharge-dependent trends. Starting at 120% SOC, dendrites appeared and increased in concentration as the SOC increased. Dendrite morphology appeared to be dependent on whether the active material was on the “dull” or “shiny” side of the copper collector. Significantly more delamination of the active material from the collector was seen on the “shiny” side of the collector particularly at 180 and 250% SOC. Transition metals were detected at 120% SOC and increased in concentration as the SOC increased. There was considerable spatial heterogeneity in the microstructures across each laminate with several regions displaying complex layered structures.