batterydata/paper-abstracts huggingface dataset:
Capacity fade is reported for 1.5 Ah Li-ion batteries containing a mixture of Li–Ni–Co–Mn oxide (NCM) + Li–Mn oxide spinel (LMO) as positive electrode material and a graphite negative electrode. The batteries were cycled at a wide range of temperatures (10 °C–46 °C) and discharge currents (0.5C–6.5C). The measured capacity losses were fit to a simple physics-based model which calculates lithium inventory loss from two related mechanisms: (1) mechanical degradation at the graphite anode particle surface caused by diffusion-induced stresses (DIS) and (2) chemical degradation caused by lithium loss to continued growth of the solid-electrolyte interphase (SEI). These two mechanisms are coupled because lithium is consumed through SEI formation on newly exposed crack surfaces. The growth of crack surface area is modeled as a fatigue phenomenon due to the cyclic stresses generated by repeated lithium insertion and de-insertion of graphite particles. This coupled chemical–mechanical degradation model is consistent with the observed capacity loss features for the NCM + LMO/graphite cells.
A process of modification of natural graphite materials as anode for lithium ion batteries was attempted. The process started with the treatment of natural graphite with concentrated hydrochloric acid and concentrated sulfuric acid in a thermal autoclave, followed by the in situ polymerization of resorcinol–formaldehyde resin to coat the graphite, then heat-treatment. SEM, XRD, Raman and electrochemical charge–discharge analysis showed that the surface defects and impurities on natural graphite were eliminated by purification of the concentrated acids, and carbon-film encapsulation modified the surface structure of the graphite and reduced its BET surface area. The as-obtained natural graphite sample presented an initial charge–discharge coulombic efficiency of 88.4% and a reversible capacity of 355.8mAhg−1. The proposed process paves a way to prepare a promising anode material with excellent performance with low cost of natural graphite for rechargeable lithium ion batteries.
Lithium iron oxides (Li x Fe y O z ) have been synthesized using LiOH and α-FeOOH by a solid-state method at various temperatures (200–800°C). The lithium iron oxide obtained at 200°C is composed of three types of structure namely, α-LiFe5O8, β-LiFe5O8, and a trace of cubic α-LiFeO2. It exhibits not only a high initial discharge capacity 215mAhg−1, but also excellent cycling retention from the 11th to the 50th cycle (95%) between 1.5 and 4.5V. On the other hand, the powder obtained at 800°C has a well-developed, single α-LiFeO2 phase and gives a very poor cycle performance below 5mAhg−1 under the same test conditions. It is also found that lithium iron oxide obtained at 200°C is first transformed into the spinel LiFe5O8 phase and is then converted into the tetragonal LiFeO2 phase after a long-term cycling. It is suggested that the tetragonal LiFeO2 phase might assist the stabilization of the original lithium iron oxide structure on cycling.
The severe corrosion accompanied with hydrogen evolution process is the main obstacle preventing the implementation of Al as an anode in alkaline batteries. It impairs the functionality of alkaline battery, due to a drastic capacity loss and a short shelf life. The possibility to reduce Al corrosion rate in alkaline solution with the use of hybrid organic∖inorganic inhibitor based on poly (ethylene glycol) di-acid (PEG di-acid) and zinc oxide (ZnO) was examined in this work. A correlation between an Al corrosion rates and the concentrations of both PEG di-acid and ZnO in alkaline is shown. Selecting 5000 ppm PEG di-acid and 16 gr/l ZnO provides substantial corrosion protection of Al, reducing the corrosion rate in a strong alkaline solution by more than one order of magnitude. Moreover, utilizing the same formulation results in increase in Al-air battery discharge capacity, from 44.5 (for a battery utilizing only KOH in the electrolyte) to 70 mhA/cm2 (for a battery utilizing ZnO/PEG di-acid hybrid inhibitor in the electrolyte). The morphology and composition of the Al electrode surface (studied by SEM, EDS, and XRD) depend on PEG di-acid and ZnO concentrations.
Although suicide remains a leading cause of death for adolescents, risk factors beyond diagnoses and suicide attempt history remain unclear. We examined whether cognitive style and temperament impact risk for an early, yet still clinically relevant and distressing, form of suicidality: active suicidal ideation. We used binary logistic regression to test whether brooding, inattention, and impulsivity predicted significantly increased risk for suicidal ideation in a sample of 134 twins, 46 of whom endorsed active suicidal ideation (i.e., probands), as well as probands’ cotwins and matched controls. When comparing probands with controls and controlling for depression diagnoses, brooding (B = 0.73, Odds Ratio [OR] = 2.07, p = 0.021), inattention (B = 1.09, OR = 2.98, p < 0.001), and impulsivity (B = 0.91, OR = 2.47, p = 0.001) differentiated probands from controls, individually. We compared probands with their cotwins using the same approach, which allowed us to account for variance in suicidal ideation risk related to twins’ shared, familial characteristics (e.g., prenatal environment, neighborhood); inattention was the only significant predictor of suicidal ideation risk (B = 0.66, OR = 1.93, p = 0.020). We then fit a logistic regression model that included all three predictors. Only inattention predicted significantly increased likelihood of suicidal ideation in proband versus controls and proband versus cotwin comparisons (B = 0.88, OR = 2.40, p = 0.024 and B = 0.67, OR = 1.96, p = 0.045, respectively). These results highlight the potential utility of examining novel, more proximal risk factors for suicidal ideation in addition to more established distal factors, like suicide attempt history and psychiatric diagnoses.
A multi-technique investigation was performed on three copper-based ionic liquids to elucidate the influence of coordinating ligands and charge-balancing anions on the electrochemical properties of the materials. Galvanostatic cycling of Cu(OHCH2CH2NH2)6(BF4)2 (Cu1) in 1-butyl-3-methyl-imidazolium hexafluorophosphate gave partially reversible plating of copper that was consistent with cyclic voltammetry data (collected using an ionic liquid-based reference electrode verified with measurements of ferrocene, cobaltocene, and lithium). Scanning electron microscopy also showed pitting in the copper-coated surface of the electrode that was consistent with the stripping wave observed by cyclic voltammetry. Potentiostatic deposition in neat Cu1 showed significant dendrite formation. The substitution of the OHCH2CH2NH2 ligands of Cu1 with stronger coordinating NH(CH2CH2OH)2 in Cu(NH(CH2CH2OH)2)6(BF4)2 (Cu2) resulted in the complete suppression of both copper stripping and dendrite formation. Substitution of the BF 4 - anions of Cu2 with CF 3 SO 3 - in Cu(NH(CH2CH2OH)2)6(CF3SO3)2 (Cu3) shifted the copper deposition 0.1V more negative and produced slightly larger spherical particles (1.5μm versus 5μm). The results suggested that while the anion composition influenced particle size, and the metal–ligand bond strength helped control particle morphology, both factors affected the electrochemical properties including the plating and stripping of copper.
Here, we designed a facile solvothermal method to prepare Li1.2Ni0.13Co0.13Mn0.54O2 hollow microspheres with considerable uniformity and monodispersity. In this method, lithium ions and transition metal carbonate have been simultaneously precipitated in the ethanol-polyethylene glycol mixed solvent system to form carbonate precursors, which subsequently transform into self-assembled hollow microspheres by a heat treatment. As cathode material for lithium ion batteries, its unique structure makes for sufficient contact between electrode and electrolyte to provide more reaction sites and shorter paths for Li+ transportation, contributing to remarkable cycling stability and excellent rate capability with improved electrochemical kinetics properties. Specifically, Li1.2Ni0.13Co0.13Mn0.54O2 hollow microspheres achieve a high initial discharge capacity of 287 mAh g−1 at 0.1 C and 234 mAh g−1 at 1 C, with capacity retentions of 85.7% and 81.3% after 100 cycles, respectively. Besides, it exhibits a high rate capacity of 150 mAh g−1 even at 5 C. Moreover, the present synthesis method could also provide an effective and promising strategy for the preparation of high energy density cathode materials for lithium ion batteries.
The aim of this study is to analyze cognitive impairment in amyotrophic lateral sclerosis (ALS). Forty-four participants matched for age, sex, and educational background were enrolled as the sporadic ALS group (n = 22) and the control group (n = 22). All participants completed comprehensive neuropsychological tests, including the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), the Stroop Color-Word Interference Test (SCWT), the Wisconsin Card Sorting Test (WCST), and the Frontal Assessment Battery. The participants underwent a series of 3.0 Tesla magnetic resonance imaging (MRI) scans. Resting-state functional MRI (Rs-fMRI) using the amplitude of low-frequency fluctuation (ALFF) was performed. Three-dimensional T1-weighted anatomical images obtained by voxel-based morphometry (VBM) were used to conduct correlation analyses and group comparisons with the demographic and neuropsychological characteristics. The results indicated that the decreased gray matter (GM) volume in the bilateral precentral gyri and increased ALFF values in the right parahippocampal gyrus, left inferior temporal gyrus, left anterior cingulate gyrus, right superior frontal gyrus, and left middle occipital gyrus were identified in the sporadic ALS group. The increased ALFF value in the right parahippocampal gyrus was positively correlated with ALS progression rate. The ALS patients exhibited poor performances on cognitive and executive tests, which were significantly or marginally significantly correlated with the ALFF values in the anterior cingulate gyrus and the frontal, temporal, and parahippocampal cortices. In conclusion, these findings provide evidence of an extramotor involvement and suggest that the ALFF value in the right parahippocampal gyrus could represent a potential marker to monitor disease progression.
There is a need for treatments targeting neurocognitive dysfunctions in schizophrenia. The aim of this study was to investigate the neurocognitive effect of aerobic high-intensity interval training (HIIT). A comparison group performed sport simulating active video gaming (AVG). We anticipated that HIIT would improve neurocognition beyond any effect of AVG, due to engagement in higher intensity cardiorespiratory demands. Recent research on the beneficial neurocognitive effect of AVG challenges this expectation but added new relevance to comparing the two interventions. This is an observer-blinded randomized controlled trial. Eighty-two outpatients diagnosed with schizophrenia were allocated to HIIT (n = 43) or AVG (n = 39). Both groups received two supervised sessions per week for 12 weeks. The attrition rate was 31%, and 65% of the participants were defined as protocol compliant study completers. Intention-to-treat analyses showed significant improvements in the neurocognitive composite score from baseline to post-intervention and from baseline to 4 months follow-up in the total sample. The same pattern of results was found in several subdomains. Contrary to our hypothesis, we found no interaction effects of time and group, indicating equal effects in both groups. Separate within-group analysis unexpectedly showed trends of differential effects in the learning domain, as HIIT showed post-intervention improvement in verbal but not visual learning, while AVG showed improvement in visual but not verbal learning. HIIT and AVG improve neurocognition equally, suggesting that both interventions may be applied to target neurocognition in schizophrenia. Future research should investigate trends towards possible differential effects of exercise modes on neurocognitive subdomains. NCT02205684, 31.07.14.
Background The purpose of this study was to evaluate the acute in vivo pump performance of a unique valveless, sensorless, pulsatile, continuous-flow total artificial heart (CFTAH) that passively self-balances left and right circulations without electronic intervention. Methods The CFTAH was implanted in two calves, with pump and hemodynamic data recorded at baseline over the full range of pump operational speeds (2,000 to 3,000 rpm) in 200-rpm increments, with pulsatility variance, and under a series of induced hemodynamic states created by varying circulating blood volume and systemic and pulmonary vascular resistance (SVR and PVR). Results Sixty of the 63 induced hemodynamic states in Case 1 and 73 of 78 states in Case 2 met our design goal of a balanced flow and maximum atrial pressure difference of 10 mm Hg. The correlation of calculated vs measured flow and SVR was high (R 2 = 0.857 and 0.832, respectively), allowing validation of an additional level of automatic active control. By varying the amplitude of sinusoidal modulation of the speed waveform, 9 mm Hg of induced pulmonary and 18 mm Hg of systemic arterial pressure pulsation were achieved. Conclusions These results validated CFTAH self-balancing of left and right circulation, induced arterial flow and pressure pulsatility, accurate calculated flow and SVR parameters, and the performance of an automatic active control mode in an acute, in vivo setting in response to a wide range of imposed physiologic perturbations.
Fracture in silicon anodes has fascinated the electrochemistry community for two decades, as it can result in a 80% capacity loss over the first few electrochemical cycles and is the limiting factor in commercializing such high capacity anodes. Although numerous experimental data exist illustrating severe fracture patterns and their dependence on the scale of the microstructure, no theoretical model has been able to re-produce and capture such behaviour. In this article, a multi-physics phase-field damage model is presented that can accurately capture the long standing problem of dry bed-lake crack patterns observed for Si thin film anodes. A promising aspect of the model is that, in addition to accounting for Li-ion diffusion, it can explicitly capture the microstructure, and therefore when applied to a Si film with a thickness below 100 nm no fracture was observed, which is consistent with experiments. As fracture in continuous thin films is random, micron-hole patterned Si films were also fabricated and cycled, resulting in ordered crack patterns. The proposed model was able to capture these elaborate, yet ordered, crack patterns, further validating its efficiency in predicting damage during lithiation of Si. This paves the way to using multiscale modeling for predicting the dimensions that limit and control fracture during lithiation, prolonging hence the electrode lifetime.
Solid-state lithium batteries have attracted significant attention recently due to their superior safety and energy density. Nevertheless, the large interfacial resistance has limited the development of SSLBs. To tackle this problem, a general strategy is to add liquid electrolytes (LE) at the interface to form a solid-liquid hybrid electrolyte. However, the effects and interfacial properties of LE in the solid-liquid hybrid electrolyte have not been well-understood. In this work, we quantitatively add LE at the interface to eliminate the large interfacial resistance and study its interfacial properties. As little as 2 µL of LE at the interface enables a hybrid LiFePO4/LATP/Li battery to deliver a specific capacity of 125 mA h g−1 at 1 C and 98 mA h g−1 at 4 C. Excess LE has no further contribution to the electrochemical performance. Furthermore, the rigid SSE could suppress the formation of lithium dendrites, especially in the case with a high cathode loading (9.1 mg/cm2), suggesting the feasibility of high energy density SSLBs using Li metal anodes. The interfacial analysis reveals that an interfacial solid-liquid electrolyte interphase (SLEI) was formed at the interface, preventing the reduction of LATP by Li metal, thus ensuring the long-term durability of LATP in LE.
Two β-glucosidase/xylosidase genes, Rubg3A and Rubg3B, were cloned from yak rumen uncultured microorganisms by metagenome method and function-based screening. Recombinant RuBG3A and RuBG3B purified from Escherichia coli were characterized for enzymatic properties, and they exhibited activity against 4-nitrophenyl-β-d-glucopyranoside and 4-nitrophenyl-β-d-xylopyranoside, suggesting bifunctional β-glucosidase/xylosidase activity. Chromatography analysis showed that they could effectively hydrolyze cellooligosaccharide substrates, indicating the facilitation in saccharification of cellulose. RuBG3A and RuBG3B can also increase the reducing sugar released in xylan hydrolysis to 218% and 169%, respectively, through synergism with xylanase, suggesting their application in hemicellulose saccharification. Molecular modeling and substrate docking showed that there should be one active center responsible for the bifunctional activity in each enzyme, since the active site pocket is substantially wide to allow the entry of both β-glucosidic or β-xylosidic substrates, which elucidated the structure–function relationship in substrate specificities. Therefore, the enzymatic properties, the participation in hydrolysis of cellooligosaccharides, and the synergism with xylanase make RuBG3A and RuBG3B very interesting candidates for saccharification of both cellulose and hemicellulose.
The accurate online estimation of cell state of charge in electric vehicles is challenging due to extensive computational requirement, measurement noise and convergence issues. This paper proposes an adaptive extended Kalman filter based state of charge determination method, which employs improved simulated annealing method to access the uncertain states and adaptive switch mechanism to adjust the estimation algorithm. It combines the advantages of the local linear approximation and noise reduction capability from extended Kalman filter with the global optimization from improved simulated annealing. The method is verified by the samples collected from battery test system. Results illustrate that the proposed method estimates the cell remained capacity with great performance despite a range of common errors from initialization, current disturbance and measurement noise.
The cyclic voltammetry characteristics of Sn2+/Sn couple in the H2SO4 medium on a graphite felt electrode is evaluated. The charge–discharge performance of Sn–V battery with VO2 +/VO2+ couple as positive part and Sn2+/Sn couple as negative part is investigated through a small laboratory cell. The result shows that though the deposition/dissolution of Sn is not a normal reversible process, Sn deposits can almost dissolve completely during the charge–discharge tests. It is remarkable that the battery could work normally at a current density of 180 mA cm−2 with an average voltage efficiency of 72%.
The superior suppression of aluminum current collector oxidation by a 1.2 M LiFSI in PYR13FSI ionic liquid electrolyte is demonstrated. Addition of EC:EMC (1:2 wt.) is shown to significantly increase the severity of parasitic aluminum oxidation. Despite leading to increased aluminum oxidation at high voltages (>4.2 V vs. Li/Li+), adding organic solvent to PYR13FSI based ionic liquids greatly enhances important electrochemical properties. The ionic conductivity and lithium ion transference number of the PYR13FSI + 1.2 M LiFSI electrolyte increase with increasing volumetric content of organic co-solvent (EC:EMC), resulting in significant improvements to high rate performance. The electrochemical benefits of organic co-solvent addition and the compatibility of the PYR13FSI + 1.2 M LiFSI electrolyte with Li(Ni1/3Mn1/3Co1/3)O2 demonstrated in this study substantiate the need to develop strategies to suppress aluminum oxidation during high voltage cycling of lithium-ion batteries in ionic liquid electrolytes.
A strong interface coupling is of vital importance to develop metal oxide/carbon nanocomposite anodes for next-generation lithium ion batteries. Herein, a rational N-doped carbon riveting strategy is designed to boost the lithium storage performance of Fe3O4/N-doped carbon tubular structures. Polypyrrole (PPy) has been used as the precursor for N-doped carbon. N-doped carbon-riveted Fe3O4/N-doped carbon (NC@Fe3O4@NC) nanocomposites were obtained by pyrolysis of PPy-coated FeOOH@PPy nanotubes in Ar atmosphere. When tested as an anode for LIBs, the NC@Fe3O4@NC displays a high reversible discharge capacity of 675.8 mA h g−1 after 100 cycles at a current density of 100 mA g−1 and very good rate capability (470 mA h g−1 at 2 A g−1), which significantly surpasses the performance of Fe3O4@NC. TEM analysis reveals that after battery cycling the FeO x particles detached from the carbon fibers for Fe3O4@NC, while for NC@Fe3O4@NC the FeO x particles were still trapped in the carbon matrix, thus preserving good electrical contact. Consequently, the superior performance of NC@Fe3O4@NC is attributed to the synergistic effect between Fe3O4 and N-doped carbon combined with the unique structure properties of the nanocomposites. The strategy reported in this work is expected to be applicable for designing other electrode materials for LIBs.
Graphene like graphite (GLG) samples containing various amounts of oxygen are prepared from the thermal reduction of graphite oxide (GO) and are used as anodes of lithium ion battery. The oxygen/carbon (O/C) ratios in GLG varied from 0 to 0.08, depending on the thermal reduction temperature, oxygen gas pressure during heat treatment and degree of oxidation of the starting GO. The cell voltage during discharge almost linearly increases below 1 V independent of the oxygen contents in them. The discharge capacity of GLG above 1 V increases with the increase in the oxygen content with a slope of lithium/oxygen ratio of 3 at lower O/C ratios. Then the slope becomes smaller and the discharge capacity reaches 673 mAhg−1 for GLG with O/C = 0.08. When GLG is treated with hydrogen gas, considerable amounts of oxygen atoms are substituted by hydrogen ones. The discharge capacity of the resulting GLG samples is larger than that expected form their oxygen contents and coulombic efficiency is slightly improved up to 59%. Introduction of oxygen atoms within carbon layers results in the large increase in the interlayer spacing during charging, which leads to accommodation of large amounts of lithium ions.
A new micro-combustor configuration for a micro fuel-cell reformer integrated with a micro-evaporator is studied experimentally and computationally. The micro-combustor as a heat source is designed for a 10–15W micro-reformer using the steam reforming method. In order to satisfy the primary requirements for designing a micro-combustor integrated with a micro-evaporator, i.e., stable burning in a small confinement and maximum heat transfer through a wall, the present micro-combustor is a simply cylinder, which is easy to fabricate, but is two-staged (expanding downstream) to control ignition and stable burning. The aspect ratio and wall thickness of the micro-combustor substantially affect ignition and thermal characteristics. For optimized design conditions, a pre-mixed micro-flame is easily ignited in the expanded second-stage combustor, moves into the smaller first-stage combustor, and finally is stabilized therein. The measured and predicted temperature distributions across the micro-combustor walls indicate that heat generated in the micro-combustor is well transferred. Thus, the present micro-combustor configuration can be applied to practical micro-reformers integrated with a micro-evaporator for use with fuel cells.