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The solution-cast method was used to prepare new solid polymer electrolytes (SPEs) that conduct potassium ions and are based on polyethylene glycol (PEG) complexed with potassium nitrate (KNO3). This polymer electrolyte system was characterized using different experimental techniques, such as X-ray diffraction (XRD), differential scanning calorimetry (DSC), composition vs. conductivity, temperature vs. conductivity, frequency-dependent conductivity, and dielectric measurements. The degree of crystallinity decreased with increasing salt concentration, according to the X-ray diffraction and DSC patterns of PEG with KNO3 salt. For PEG: KNO3 (80 : 20) composition, an optimum conductivity of 8.24× KT−6 S/cm was recorded at 30 °C. Compared with pure PEG, the optimum conducting composition (OCC) conductivity increased by two orders of magnitude. The temperature range of 303 to 333 K was used for the temperature-dependent conductivity experiments. The findings demonstrate that the conductivity obeys the Arrhenius rule and increases as the temperature rises. A dc plateau and a dispersive zone were observed in the conductance spectrum, which also follows Jonscher's power law. It was investigated how temperature and frequency affect the dielectric permittivity. An electrochemical cell with the configuration K/(80PEG : 20KNO3)/(I2+C+electrolyte) was constructed using an 80 : 20 electrolyte system, and its discharge properties were investigated. The cell's open circuit voltage was measured at 2.48 V. [ABSTRACT FROM AUTHOR]

Strong magnetic fields are required in many fields, such as medicine (magnetic resonance imaging), pharmacy (nuclear magnetic resonance), particle accelerators (such as the Large Hadron Collider) and fusion devices (for example, the International Thermonuclear Experimental Reactor, ITER), as well as for other diverse scientific and industrial uses. For almost two decades, 45 tesla has been the highest achievable direct-current (d.c.) magnetic field; however, such a field requires the use of a 31-megawatt, 33.6-tesla resistive magnet inside 11.4-tesla low-temperature superconductor coils.sup.1, and such high-power resistive magnets are available in only a few facilities worldwide.sup.2. By contrast, superconducting magnets are widespread owing to their low power requirements. Here we report a high-temperature superconductor coil that generates a magnetic field of 14.4 tesla inside a 31.1-tesla resistive background magnet to obtain a d.c. magnetic field of 45.5 tesla--the highest field achieved so far, to our knowledge. The magnet uses a conductor tape coated with REBCO (REBa.sub.2Cu.sub.3O.sub.x, where RE = Y, Gd) on a 30-micrometre-thick substrate.sup.3, making the coil highly compact and capable of operating at the very high winding current density of 1,260 amperes per square millimetre. Operation at such a current density is possible only because the magnet is wound without insulation.sup.4, which allows rapid and safe quenching from the superconducting to the normal state.sup.5-10. The 45.5-tesla test magnet validates predictions.sup.11 for high-field copper oxide superconductor magnets by achieving a field twice as high as those generated by low-temperature superconducting magnets. A copper oxide high-temperature superconductor magnet generates a direct-current magnetic field of 45.5 tesla--the highest value reported so far--using a design that enables operation at high current densities., Author(s): Seungyong Hahn [sup.1] [sup.2] , Kwanglok Kim [sup.1] , Kwangmin Kim [sup.1] , Xinbo Hu [sup.1] , Thomas Painter [sup.1] , Iain Dixon [sup.1] , Seokho Kim [sup.1] [sup.3] [...]