Charge Transport and Glassy Dynamics in Blends Based on 1-Butyl-3-vinylbenzylimidazolium Bis(trifluoromethanesulfonyl)imide Ionic Liquid and the Corresponding Polymer

Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic liquid (IL) and the corresponding polymer (polyIL) were examined by Pulsed-Field-Gradient Nuclear Magnetic Resonance (PFG-NMR) and rheology coupled with broadband dielectric spectroscopy (rheo-BDS). We found that the mechanical storage modulus (G′) increases with an increasing amount of polyIL and G′ is a factor of 10,000 higher for the polyIL compared to the monomer (G′$_{IL}$= 7.5 Pa at 100 rad s$^{-1}$ and 298 K). Furthermore, the ionic conductivity (σ$_{0}$) of the IL is a factor 1000 higher than its value for the polymerized monomer with 3.4×10$^{-4}$ S cm$^{-1}$ at 298 K. Additionally, we found the Haven Ratio (H$_{R}$) obtained through PFG-NMR and BDS measurements to be constant around a value of 1.4 for the IL and blends with 30 wt% and 70 wt% polyIL. These results show that blending of the components does not have a strong impact on the charge transport compared to the charge transport in the pure IL at room temperature, but blending results in substantial modifications of the mechanical properties. Furthermore, it is highlighted that the increase in σ$_{0}$ might be attributed to the addition of a more mobile phase, which also possibly reduces ion-ion correlations in the polyIL

Poly(ethylene oxide)-Based Electrolytes for Solid-State Potassium Metal Batteries with a Prussian Blue Positive Electrode

Potassium-ion batteries are an emerging post-lithium technology that are considered ecologically and economically benign in terms of raw materials’ abundance and cost. Conventional cell configurations employ flammable liquid electrolytes that impose safety concerns, as well as considerable degrees of irreversible side reactions at the reactive electrode interfaces (especially against potassium metal), resulting in a rapid capacity fade. While being inherently safer, solid polymer electrolytes may present a solution to capacity losses owing to their broad electrochemical stability window. Herein, we present for the first time a stable solid-state potassium battery composed of a potassium metal negative electrode, a Prussian blue analogue K₂Fe[Fe(CN)₆] positive electrode, and a poly(ethylene oxide)-potassium bis(trifluoromethanesulfonyl)imide polymer electrolyte. At an elevated operating temperature of 55 °C, the solid-state battery achieved a superior capacity retention of 90% over 50 cycles in direct comparison to a conventional carbonate-based liquid electrolyte operated at ambient temperature with a capacity retention of only 66% over the same cycle number interval

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Multi-messenger Observations of a Binary Neutron Star Merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∼ 1.7 {{s}} with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of {40}-8+8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 {M}ȯ . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∼ 40 {{Mpc}}) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∼ 9 and ∼ 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.</p

Datasets to Impact of Nano-sized Inorganic Fillers on PEO-based Electrolytes for Potassium Batteries

&lt;p&gt;This dataset provides the raw data to the manuscript&lt;/p&gt;&lt;p&gt;&lt;strong&gt;"Impact of Nano‐Sized Inorganic Fillers on PEO‐Based Electrolytes for Potassium Batteries"&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;published in Batteries &amp; Supercaps, &lt;strong&gt;2023&lt;/strong&gt;, e202300404. https://doi.org/10.1002/batt.202300404&lt;/p&gt;&lt;p&gt;&nbsp;&lt;/p&gt;&lt;p&gt;Specifically, the following measurements are provided in separate zip folders:&lt;/p&gt;&lt;p&gt;Solid polymer electrolytes characterization:&lt;/p&gt;&lt;p&gt;Differential Scanning Calorimetry ("DSC.zip")&lt;/p&gt;&lt;p&gt;Rheological measurements ("Rheology.zip")&lt;/p&gt;&lt;p&gt;Electrochemical Impedance Spectroscopy ("PEIS.zip")&lt;/p&gt;&lt;p&gt;Plating and Stripping Experiments ("Plating-Stripping.zip")&lt;/p&gt;&lt;p&gt;Galvanostatic Cycling with Potential Limitations (GCPL.zip)&lt;/p&gt;&lt;p&gt;&nbsp;&lt;/p&gt;&lt;p&gt;Experimental and sample details, including assignment to filenames are provided in the respective README files.&lt;/p&gt

Styrene-Based Poly(ethylene oxide) Side-Chain Block Copolymers as Solid Polymer Electrolytes for High-Voltage Lithium-Metal Batteries

Herein, we report the design of styrene-based poly(ethylene oxide) (PEO) side-chain block copolymers featuring a microphase separation and their application as solid polymer electrolytes in high-voltage lithium-metal batteries. A straightforward synthesis was established, overcoming typical drawbacks of PEO block copolymers prepared by anionic polymerization or ester-based PEO side-chain copolymers. Both the PEO side-chain length and the LiTFSI content were varied, and the underlying relationships were elucidated in view of polymer compositions with high ionic conductivity. Subsequently, a selected composition was subjected to further analyses, including phase-separated morphology, providing not only excellent self-standing films with intrinsic mechanical stability but also the ability to suppress lithium dendrite growth as well as good flexibility, wettability, and good contacts with the electrodes. Furthermore, good thermal and electrochemical stability was demonstrated. To do so, linear sweep and cyclic voltammetry, lithium plating/stripping tests, and galvanostatic overcharging using high-voltage cathodes were conducted, demonstrating stable lithium-metal interfaces and a high oxidative stability of around 4.75 V. Consequently, cycling of Li||NMC622 cells did not exhibit commonly observed rapid cell failure or voltage noise associated with PEO-based electrolytes in Li||NMC622 cells, attributed to the high mechanical stability. A comprehensive view is provided, highlighting that the combination of PEO and high-voltage cathodes is not impossible per se

Advanced Block Copolymer Design for Polymer Electrolytes: Prospects of Microphase Separation

Herein, we report on an advanced design for polymer electrolytes (PEs) based on our previously reported microphase-separated poly(vinyl benzyl methoxy poly(ethylene oxide) ether)-block-polystyrene block copolymers (PVBmPEO-b-PS). Usually, such block copolymers are characterized by a high mechanical stability provided by the PS domain, while the PEO-based domain features decent ionic conductivities, however, mostly only at higher temperatures. To enable suitable ionic conductivities at lower temperatures, we selectively implemented two ionic liquids (ILs) as a model plasticizer for the PEO domain. Since those ILs are nonmiscible with PS, the latter domain is unaffected, thus still providing a great mechanical stability. To maintain the necessary self-standing film forming ability, we adjusted the size of the PS domain to match with the conducting PEO-based domain. For this, a series of four block copolymers with different PS:PVBmPEO block ratios were synthesized, thus enabling the study of the influence of different amounts of IL. Further, all derived polymer electrolytes were thoroughly characterized by thermal, rheological, morphological, and electrochemical analyses. We could prove the microphase-separated morphology with long-range order and a good thermal and mechanical stability as well as the selective mixing of the ILs within the conducting domain. Consequently, electrochemical impedance spectroscopy revealed a significant increase in ionic conductivity up to 2 orders of magnitude and a reduced interfacial resistance in comparison to a nonplasticized reference sample. Moreover, exhaustive studies of the lithium-ion transference number showed not only the importance of such detailed analysis for IL-containing PEs but also the true increase of the effective lithium-ion conductivity. Finally, we conducted a full cycling in Li||LiFePO4 (LFP) cells to clearly demonstrate the applicability of our approach