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The high areal-energy and power requirements of advanced microelectronic devices favor the choice of a lithium-ion system, since it provides the highest energy density of available battery technologies suitable for a variety of applications. Several attempts have been made to produce primary and secondary thin-film batteries utilizing printing techniques. These technologies are still at an early stage, and most currently-printed batteries exploit printed electrodes sandwiching self-standing commercial polymer membranes, produced by conventional extrusion or papermaking techniques, followed by soaking in non-aqueous liquid electrolytes. In this work, we suggest a novel flexible-battery design and report the initial results of development and characterization of novel 3D printed allsolid-state electrolytes prepared by fused-filament fabrication (FFF). The electrolytes are composed of LiTFSI, polyethylene oxide (PEO), which is a known lithium-ion conductor, and polylactic acid (PLA) for enhanced mechanical properties and high-temperature durability. The 3D printed electrolytes were characterized by means of ESEM imaging, mass spectroscopy, differential scanning calorimetry (DSC) and electrochemical impedance spectroscopy (EIS). TOFSIMS analysis reveals formation of lithium complexes with both polymers. The flexible all-solid LiTFSI-based electrolyte exhibited bulk ionic conductivity of 3 × 10 −5 S/cm at 90°C and 156ohmxcm 2 resistance of the solid electrolyte interphase (SEI). We believe that the coordination mechanism of the lithium cation by the oxygen of the PLA chain is similar to that of PEO and local relaxation motions of PLA chain segments could promote Li-ion hopping between oxygens of adjacent CH-O groups. What is meant by this is that PLA not only improves the mechanical properties of PEO, but also serves as a Li-ion-conducting medium. These results pave the way for a fully printed solid battery, which enables free-form-factor flexible geometries.

We report a comparative study of the magnetic and magnetoresistance phenomena in two types of granular ferromagnets: ferromagnet-normal-metal mixtures Ni-Ag, Co-Ag, and ferromagnet-insulator mixtures Ni-SiO 2 , Co-SiO 2 . Anisotropic magnetoresistance and giant magnetoresistance ͑GMR͒ are identified in both types of systems above and below the magnetic component percolation threshold respectively. The GMR effect in granular ferromagnets is shown to be essentially independent of the nature and resistance of the nonmagnetic intergranular matrix.

Transport properties including conductivity and magnetoconductance have been measured for amorphous nickel-silicon films. This study focuses on metallic amorphous a-Ni x Si 1−x films, located just above the metal-insulator transition (MIT). Using various techniques, the MIT was identified. Electron-electron interactions dominated the conductivity, where σ ≈ σ (0) + CT 0.55. Strong spin-orbit scattering was important in the weak-localization contribution to the magnetoconductance data for the metallic films. The inelastic scattering time was extracted from the magnetoconductance data. The low-temperature magnetoconductance data versus Ni content x exhibited a negative maximum just above the critical concentration x c , suggesting another technique for identifying the MIT.

Omniphobic metallic surfaces obtained with a robust two-stage process are reported. The surfaces demonstrate high apparent contact angles accompanied with a low contact angle hysteresis for a variety of liquids, including water, diidomethane, canola, castor, silicone oils, and crude petroleum oil. The superoleophobicity was achieved by fluorination of the nano-rough aluminum surfaces under treatment with perfluorononanoic acid, as established by TOF-SIMS spectrometry. The stability of the Cassie wetting regime was investigated. The critical surface tension of a liquid corresponding to the onset of wetting transitions was established experimentally.

The evolution of microstructure in Al and Cu thin film lines during electromigration has been studied using a transmission electron microscopy. Grain boundary migration was found to be critically involved in the electromigration induced hillock formation that can be described as a three-dimensional growth of a single grain.

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