10 research outputs found
Superior Electrochemical Performance of a Ni-P/Si Negative Electrode for Li-ion Batteries in an Ionic Liquid Electrolyte
To achieve electrode performance with both high capacity and long cycle life, we investigated the effect of the anion structure in an ionic liquid electrolyte on the electrochemical performance of an annealed Ni-P/(etched Si) negative electrode for Li-ion batteries. The electrode maintained a discharge capacity of 1890 mA h g-1 after 250 cycles in bis(fluorosulfonyl)amide-based ionic liquid electrolyte, which was approximately three times higher than that in bis(trifluoromethanesulfonyl)amide-based electrolyte
Electrochemical performance of Sn4P3 negative electrode for Na-ion batteries in ether-substituted ionic liquid electrolyte
We have previously disclosed that the ionic-liquid electrolyte sodium bis(fluorosulfonyl)amide (NaFSA)/1-methyl-1-propylpyrrolidinium bis(fluorosulfonyl)amide (Py13-FSA) can significantly improve the cycling stability of Sn4P3 negative electrodes for Na-ion batteries (NIBs). However, the strong electrostatic interaction between Na+ and FSAā in the electrolyte leads to high viscosity and low conductivity. In this study, we have tried to improve the conductivity of the electrolyte and enhance the rate capability of the Sn4P3 electrode by introducing an ether group in the side-chain of the ionic liquid cation to reduce said electrostatic interaction. Ether-substituted ionic liquid 1-methoxymethyl-1-methylpyrrolidinium (PyMOM)-FSA showed higher conductivity than Py13-FSA and the Sn4P3 electrode exhibited a higher rate capability. The differential capacity vs. potential plots suggest that the reaction between Na+ and Sn or P is promoted in the ether-substituted ionic liquid electrolyte. These results demonstrate that introduction of an ether moiety is an effective approach to improve the rate capability of the Sn4P3 electrode in NIBs
Effect of Annealing Temperature of Ni-P/Si on its Lithiation and Delithiation Properties
Annealed NiāPācoated Si (NiāP/Si) anodes for lithium-ion batteries have shown a superior cycle life with discharge capacity of 1000 mA h gā1 over 1100 cycles in some ionic-liquid electrolytes. However, the annealing temperature has yet to be optimized for NiāP/Si electrodes. We investigated the electrochemical performance of NiāP/Si electrode annealed at various temperatures in this study. The NiāP/Si electrodes annealed at 800 Ā± 20 Ā°C exhibited a superior cycle life with a reversible capacity of 1000 mA h gā1 over 1000 cycles, whereas the capacity of the electrodes annealed at temperatures of 750 Ā°C and 850 Ā°C faded at approximately 500 cycles. At 800 Ā°C, a newly formed NiSi2 phase was theorized to significantly contribute to improving adhesion between the NiāP coating layer and the Si particles. The NiāP coating particles tended to aggregate at 850 Ā°C, leading to a reduction in the coating effect, that is, a decline in their reactivity with Li+, acceleration of electrode disintegration, and a reduction in electrical conductivity. On the other hand, NiāP/Si electrodes annealed at 850 Ā°C exhibited a superior rate performance. The amount of available NiSi2 which ultimately contributed to higher reactivity with Li should increase
Piperidinium-Based Ionic Liquids as an Electrolyte Solvent for Li-Ion Batteries: Effect of Number and Position of Oxygen Atom in Cation Side Chain on Electrolyte Property
ArticleJournal of The Electrochemical Society. 167(7): 174101 (2019)journal articl
Plaque REgression with Cholesterol absorption Inhibitor or Synthesis inhibitor Evaluated by IntraVascular UltraSound (PRECISE-IVUS Trial): Study protocol for a randomized controlled trial
AbstractBackgroundAlthough the positive association between achieved low-density lipoprotein cholesterol (LDL-C) level and the risk of coronary artery disease (CAD) has been confirmed by randomized studies with statins, many patients remain at high residual risk of events suggesting the necessity of novel pharmacologic strategies. The combination of ezetimibe/statin produces greater reductions in LDL-C compared to statin monotherapy.PurposeThe Plaque REgression with Cholesterol absorption Inhibitor or Synthesis inhibitor Evaluated by IntraVascular UltraSound (PRECISE-IVUS) trial was aimed at evaluating the effects of ezetimibe addition to atorvastatin, compared with atorvastatin monotherapy, on coronary plaque regression and change in lipid profile in patients with CAD.MethodsThe study is a prospective, randomized, controlled, multicenter study. The eligible patients undergoing IVUS-guided percutaneous coronary intervention will be randomly assigned to receive either atorvastatin alone or atorvastatin plus ezetimibe (10mg) daily using a web-based randomization software. The dosage of atorvastatin will be increased by titration within the usual dose range with a treatment goal of lowering LDL-C below 70mg/dL based on consecutive measures of LDL-C at follow-up visits. IVUS will be performed at baseline and 9ā12 months follow-up time point at participating cardiovascular centers. The primary endpoint will be the nominal change in percent coronary atheroma volume measured by volumetric IVUS analysis.ConclusionPRECISE-IVUS will assess whether the efficacy of combination of ezetimibe/atorvastatin is noninferior to atorvastatin monotherapy for coronary plaque reduction, and will translate into increased clinical benefit of dual lipid-lowering strategy in a Japanese population
Impact of Dual Lipid-Lowering Strategy With Ezetimibe and Atorvastatin on Coronary Plaque Regression in Patients With Percutaneous Coronary Intervention The Multicenter Randomized Controlled PRECISE-IVUS Trial
AbstractBackgroundDespite standard statin therapy, a majority of patients retain a high āresidual riskā of cardiovascular events.ObjectivesThe aim of this study was to evaluate the effects of ezetimibe plus atorvastatin versus atorvastatin monotherapy on the lipid profile and coronary atherosclerosis in Japanese patients who underwent percutaneous coronary intervention (PCI).MethodsThis trial was a prospective, randomized, controlled, multicenter study. Eligible patients who underwent PCI were randomly assigned to atorvastatin alone or atorvastatin plus ezetimibe (10 mg) daily. Atorvastatin was uptitrated with a treatment goal of low-density lipoprotein cholesterol (LDL-C)Ā <70 mg/dl. Serial volumetric intravascular ultrasound was performed at baseline and again at 9 to 12 months to quantify the coronary plaque response in 202 patients.ResultsThe combination of atorvastatin/ezetimibe resulted in lower levels of LDL-C than atorvastatin monotherapy (63.2 Ā± 16.3 mg/dl vs. 73.3 Ā± 20.3 mg/dl; pĀ < 0.001). For the absolute change in percent atheroma volume (PAV), theĀ mean difference between the 2 groups (ā1.538%; 95% confidence interval [CI]: ā3.079% to 0.003%) did not exceedĀ the pre-defined noninferiority margin of 3%, but the absolute change in PAV did show superiority for the dual lipid-lowering strategy (ā1.4%; 95% CI: ā3.4% to ā0.1% vs. ā0.3%; 95% CI: ā1.9% to 0.9% with atorvastatin alone; pĀ =Ā 0.001). For PAV, a significantly greater percentage of patients who received atorvastatin/ezetimibe showed coronary plaque regression (78% vs. 58%; pĀ = 0.004). Both strategies had acceptable side effect profiles, with a low incidence ofĀ laboratory abnormalities and cardiovascular events.ConclusionsCompared with standard statin monotherapy, the combination of statin plus ezetimibe showed greater coronary plaque regression, which might be attributed to cholesterol absorption inhibitionāinduced aggressive lipid lowering. (Plaque Regression With Cholesterol Absorption Inhibitor or Synthesis Inhibitor Evaluated by Intravascular Ultrasound [PRECISE-IVUS]; NCT01043380
Design of ionic liquids as liquid desiccant for an air conditioning system
Suitable control of the humidity can contribute to electric energy savings. However, the present dehumidification system has many weak points. The liquid desiccant air-conditioning system has recently gained growing interest from the stand point of reducing energy consumption during dehumidification. In order to find the appropriate ionic liquids (ILs) as a desiccant for the liquid desiccant air-conditioner system, we conducted a systematic evaluation of the humidification capability of 16 types of ILs. Among the tested ILs, tributyl(methyl)phosphonium dimethyl phosphate ([P4441][DMPO4]) exhibited the best dehumidification capacity and had a less corrosive effect on four types of metals as possible piping materials. It should be noted that this [P4441][DMPO4] has a very stable nature and produced no odor while conducting the experiment and storing for over 1Ā year at room temperature under ambient conditions. Furthermore, it was revealed that a 77% (w/w) aqueous solution of [P4441][DMPO4] worked as an efficient desiccant liquid for the liquid desiccant air-conditioner system. Keywords: Dehumidification, Liquid desiccant, Ionic liquids, Air-conditioner system, Phosphonium IL