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The electrochemical signals are very important to analyze and regulate the electrochemical systems, and the electrochemical oscillation is a newly discovered electrochemical signal in Li-ion batteries (LIBs), including the voltage and current oscillations. In this work, the Li4Ti5O12 was prepared using a home-made spray-drying instrument and high-temperature sintering, and its electrochemical oscillation was studied in LIBs. The electrochemical oscillation arose when the as-prepared Li4Ti5O12 precursor was sintered in a powder (not pellet) form, and it became stronger by reducing the lithium content in Li4Ti5O12. There are two types of electrochemical oscillation as a single-period oscillation or a double-period oscillation, and they can be transformed through varying the operating temperature, the current rate, and the conductive agent ratio, which might be owing to the electrochemical kinetics of Li4Ti5O12 electrodes. Combining the sintered forms and the X-ray photoelectron spectroscopy results, whether there is some fresh surface (formed by grinding the sintered pellet) becomes a typical difference between the powder-sintered and pellet-sintered Li4Ti5O12, which would affect the nucleation step and the reaction kinetics, and we proposed a possible reaction process of the electrochemical oscillation during the galvanostatic charging process of Li4Ti5O12 in LIBs.

Na3V2(PO4)3 (NVP) is a promising electrode material for sodium‐ion batteries. However, many of its electrochemical properties like ionic conductivities have never been systematically studied. In the present paper, a battery cell with controlled morphology of NVP was prepared and the electrochemical impedance spectra were measured at various voltages. The ionic conductivity of NVP was calculated in dependence on applied potentials. NVP has a total conductivity of 1×10−6 S cm−1 at 2.9 V, which decreases to 8×10−8 S cm−1 at 3.5 V. This low conductivity, especially at higher voltages, influences the performance of batteries with an NVP electrode, especially by limiting the high‐rate cycling of solid‐state batteries.

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A stable filamentous coaxial microelectrode of olivine LiFePO4 was fabricated by using a facile spray drying method.

With the development of portable electronic devices, it is an urgent demand to miniaturize energy storage components, especially for Li-ion batteries, and the thin-film electrode is a promising miniaturization strategy. In this work, we successfully fabricated a binder-free thin-film electrode of LiFePO4/C by a spray drying method. According to the scanning electron microscopy, the Al-foil substrate was coated with a porous LiFePO4/C layer of ca. 4 µm thick, and the X-ray diffraction and the Raman spectra reveal the good crystallization of LiFePO4 and the presence of amorphous carbon. The as-prepared electrode exhibits an excellent cycle stability, which works quite good even after 2000 cycles. Thereby, we suggested that the as-prepared binder-free thin-film electrode can be potentially applied in the field of all-solid-state, flexible, and micro Li-ion batteries.

The wide-spread use of contrast-enhanced imaging is often combined with pharmaco-kinetic modeling to estimate the level of perfusion and/or permeability of the tissue or tumour under investigation. Despite the availability of advanced experimental methods and phantoms to test the accuracy of blood flow and transfer rates, the reliable estimation of tissue permeability following kinetic modeling against a known truth is still outstanding. This work reports on the first two phases of the development of a tissue mimicking permeable hepatic perfusion phantom being tested under DCE-CT: material selection and fabrication, as well as property testing. The required properties of these synthetic materials include a tailored porous structure, tumor mimicking pore size and tumor mimicking permeability. Three phantom materials were investigated for their capabilities to address these requirements, i.e. polydimethylsiloxane (PDMS), thermoplastic polyurethane (TPU) and agar gel. Porous structures were made using different techniques such as phase separation micro-molding (for PDMS) and a particular leaching process (for PDMS and TPU). Manual pores were made on agar gel and all were characterized under SEM, micro-CT scan and pycnometer. TPU was selected as the phantom material of choice moving forward due to its high homogeneity in pore size ranging from 200 to 400 μm, which mimics tumor vasculature the best. TPU also has the highest permeability of the three materials and its stable structure provides good repeatability.