Effects of Ion Fraction in an Inorganic Ionic Liquid Electrolyte on Performance of Intermediate-Temperature Operating Sodium-Sulfur Batteries

Sodium-sulfur (Na-S) batteries are promising energy storage systems for renewable energy sources which redeem an intermittent energy source. This study reports the effects of the Na[SO₃CF₃] fraction in an inorganic Na[SO₃CF₃]-Cs[N(SO₂CF₃)₂] ionic liquid electrolyte (x(Na[SO₃CF₃]) = 0.2, 0.3, and 0.4) on the performance of Na-S batteries. Measurements of physicochemical and electrochemical properties demonstrated that decrease in the Na[SO₃CF₃] fraction decreases viscosity and increases ionic conductivity and the solubility of polysulfides into the ionic liquid, which contributes to the enhanced capacity in the low potential region during discharging

Potassium single cation ionic liquid electrolyte for potassium-ion batteries

Potassium-ion batteries (PIBs) are a promising post-lithium-ion battery (LIB), as their resources are abundant and low-cost and may have a higher voltage than LIBs. However, the high operating voltage and extremely high reactivity of potassium metal require a chemically safe electrolyte with oxidative and reductive stabilities. In this study, a potassium single cation ionic liquid (K-SCIL), which contains only K⁺ as the cationic species and has a high electrochemical stability, low flammability, and low vapor pressure, is developed as an electrolyte for PIBs. The mixture of potassium bis(fluorosulfonyl)amide and potassium (fluorosulfonyl)(trifluoromethylsulfonyl)amide at a molar ratio of 55:45 had the lowest melting point of 67 °C. The K⁺ concentration in this K-SCIL is high (8.5 mol dm⁻³ at 90 °C) due to the absence of solvents and bulky organic cations. In addition, the electrochemical window is as wide as 5.6 V, which enables the construction of PIBs with a high energy density. A high current density can be achieved with this K-SCIL, owing to the absence of a K⁺ concentration gradient. The electrolyte was successfully used with a graphite negative electrode, enabling the reversible intercalation/deintercalation of K⁺, as confirmed by X-ray diffraction

バイオマスガス化技術の実用化研究及びエネルギー作物を利用した放射線汚染地域への適用に関する検討

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 大島 義人, 東京大学教授 徳永 朋祥, 東京大学教授 森口 祐一, 東京大学准教授 大友 順一郎, 東京大学准教授 佐藤 弘泰University of Tokyo(東京大学

Potassium Difluorophosphate as an Additive for Potassium Ion Batteries

The limited cyclability and inferior Coulombic efficiency of graphite negative electrodes have been major impediments to their practical utilization in potassium-ion batteries (PIBs). Herein, for the first time, potassium difluorophosphate (KDFP) electrolyte additive is demonstrated as a viable solution to these bottlenecks by facilitating the formation of a stable and K⁺-conducting solid–electrolyte interphase (SEI) on graphite. The addition of 0.2 wt % KDFP to the electrolyte results in significant improvements in the (de)potassiation kinetics, capacity retention (76.8% after 400 cycles with KDFP vs 27.4% after 100 cycles without KDFP), and average Coulombic efficiency (∼99.9% during 400 cycles) of the graphite electrode. Moreover, the KDFP-containing electrolyte also enables durable cycling of the K/K symmetric cell at higher efficiencies and lower interfacial resistance as opposed to the electrolyte without KDFP. X-ray diffraction and Raman spectroscopy analyses have confirmed the reversible formation of a phase-pure stage-1 potassium–graphite intercalation compound (KC₈) with the aid of KDFP. The enhanced electrochemical performance by the KDFP addition is discussed based on the analysis of the SEI layer on graphite and K metal electrodes by X-ray photoelectron spectroscopy

Potassium Difluorophosphate as an Electrolyte Additive for Potassium Ion Batteries

The limited cyclability and inferior Coulombic efficiency of graphite negative electrodes have been major impediments to their practical utilization in potassium-ion batteries (PIBs). Herein, for the first time, potassium difluorophosphate (KDFP) electrolyte additive is demonstrated as a viable solution to these bottlenecks by facilitating the formation of a stable and K⁺-conducting solid–electrolyte interphase (SEI) on graphite. The addition of 0.2 wt % KDFP to the electrolyte results in significant improvements in the (de)potassiation kinetics, capacity retention (76.8% after 400 cycles with KDFP vs 27.4% after 100 cycles without KDFP), and average Coulombic efficiency (∼99.9% during 400 cycles) of the graphite electrode. Moreover, the KDFP-containing electrolyte also enables durable cycling of the K/K symmetric cell at higher efficiencies and lower interfacial resistance as opposed to the electrolyte without KDFP. X-ray diffraction and Raman spectroscopy analyses have confirmed the reversible formation of a phase-pure stage-1 potassium–graphite intercalation compound (KC₈) with the aid of KDFP. The enhanced electrochemical performance by the KDFP addition is discussed based on the analysis of the SEI layer on graphite and K metal electrodes by X-ray photoelectron spectroscopy

Potassium Difluorophosphate as an Electrolyte Additive for Potassium Ion Batteries

The limited cyclability and inferior Coulombic efficiency of graphite negative electrodes have been major impediments to their practical utilization in potassium-ion batteries (PIBs). Herein, for the first time, potassium difluorophosphate (KDFP) electrolyte additive is demonstrated as a viable solution to these bottlenecks by facilitating the formation of a stable and K⁺-conducting solid–electrolyte interphase (SEI) on graphite. The addition of 0.2 wt % KDFP to the electrolyte results in significant improvements in the (de)potassiation kinetics, capacity retention (76.8% after 400 cycles with KDFP vs 27.4% after 100 cycles without KDFP), and average Coulombic efficiency (∼99.9% during 400 cycles) of the graphite electrode. Moreover, the KDFP-containing electrolyte also enables durable cycling of the K/K symmetric cell at higher efficiencies and lower interfacial resistance as opposed to the electrolyte without KDFP. X-ray diffraction and Raman spectroscopy analyses have confirmed the reversible formation of a phase-pure stage-1 potassium–graphite intercalation compound (KC₈) with the aid of KDFP. The enhanced electrochemical performance by the KDFP addition is discussed based on the analysis of the SEI layer on graphite and K metal electrodes by X-ray photoelectron spectroscopy

The Nutritional Status of Japanese Black Breeding Cows Grazed in a Larger Abandoned Paddy Field

Because rice consumption has decreased in Japan, the number of abandoned paddy fields has increased. Some of the abandoned paddy fields are being used for livestock grazing, effectively using the abandoned fields and reducing the production costs on livestock farms. Such grazing may use an integrated grazing system of scattered small pastures where each of the small abandoned paddy fields scattered in a given agriculture area is defined as one grazing yard, and a herd consisting of two or three head of cattle is moved from one grazing yard to another. However, because the number of abandoned paddy fields has increased, it may be possible to have cattle grazing in larger fields made by combining multiple abandoned paddy fields (Shindo and Tejima 2006). Here we examined the nutritional status of Japanese Black breeding cows that stayed in larger-sized abandoned paddy fields to graze from spring to autumn

Right thoracic curvature in the normal spine

<p>Abstract</p> <p>Background</p> <p>Trunk asymmetry and vertebral rotation, at times observed in the normal spine, resemble the characteristics of adolescent idiopathic scoliosis (AIS). Right thoracic curvature has also been reported in the normal spine. If it is determined that the features of right thoracic side curvature in the normal spine are the same as those observed in AIS, these findings might provide a basis for elucidating the etiology of this condition. For this reason, we investigated right thoracic curvature in the normal spine.</p> <p>Methods</p> <p>For normal spinal measurements, 1,200 patients who underwent a posteroanterior chest radiographs were evaluated. These consisted of 400 children (ages 4-9), 400 adolescents (ages 10-19) and 400 adults (ages 20-29), with each group comprised of both genders. The exclusion criteria were obvious chest and spinal diseases. As side curvature is minimal in normal spines and the range at which curvature is measured is difficult to ascertain, first the typical curvature range in scoliosis patients was determined and then the Cobb angle in normal spines was measured using the same range as the scoliosis curve, from T5 to T12. Right thoracic curvature was given a positive value. The curve pattern was organized in each collective three groups: neutral (from -1 degree to 1 degree), right (> +1 degree), and left (< -1 degree).</p> <p>Results</p> <p>In child group, Cobb angle in left was 120, in neutral was 125 and in right was 155. In adolescent group, Cobb angle in left was 70, in neutral was 114 and in right was 216. In adult group, Cobb angle in left was 46, in neutral was 102 and in right was 252. The curvature pattern shifts to the right side in the adolescent group (p < 0.01) and in adult group (p < 0.001) compared to the child group. There was no significant difference in curvature pattern between adolescent and adult group.</p> <p>Conclusions</p> <p>Based on standing chest radiographic measurements, a right thoracic curvature was observed in normal spines after adolescence.</p

Idiopathic Pneumonia Syndrome Refractory to Ruxolitinib after Post-Transplant Cyclophosphamide-based Haploidentical Hematopoietic Stem Cell Transplantation: Lung Pathological Findings from an Autopsy Case

A 69-year-old Japanese man with acute leukemia received post-transplant cyclophosphamide-based haploidentical stem cell transplantation (PTCY-haplo-SCT) but was readmitted with dyspnea and ground-glass-opacities of the lungs. Bronchoscopy showed inflammatory changes with no signs of infection. He received steroids but required intubation as his condition deteriorated. In addition to antithymocyte globulin and cyclophosphamide, we administered ruxolitinib but failed to save him. Autopsy findings revealed fibrotic nonspecific interstitial pneumonia (NSIP) without evidence of organizing pneumonia or infection. Thus, we diagnosed idiopathic pneumonia syndrome (IPS). As far as our knowledge, this is the first case of IPS with NSIP histology after PTCY-haplo-SCT