With the increase of interest in the application of piezoelectric polyvinylidene fluoride (PVDF) in nanogenerators (NGs), sensors, and microdevices, the most efficient and suitable methods of their synthesis are being pursued. Electrospinning is an effective method to prepare higher content β-phase PVDF nanofiber films without additional high voltage poling or mechanical stretching, and thus, it is considered an economically viable and relatively simple method. This work discusses the parameters affecting the preparation of the desired phase of the PVDF film with a higher electrical output. The design and selection of optimum preparation conditions such as solution concentration, solvents, the molecular weight of PVDF, and others lead to electrical properties and performance enhancement in the NG, sensor, and other applications. Additionally, the effect of the nanoparticle additives that showed efficient improvements in the PVDF films was discussed as well. For instance, additives of BaTiO₃, carbon nanotubes, graphene, nanoclays, and others are summarized to show their contributions to the higher piezo response in the electrospun PVDF. The recently reported applications of electrospun PVDF films are also analyzed in this review paper.

Nanostructured magnesium nickel oxide (Mg_0.6Ni_0.4O) was synthesized by a self-propagating high temperature synthesis method followed by heat treatment. The particles of the resulting oxide were used as additives to prepare the sulfur/polyacrylonitrile/Mg_0.6Ni_0.4O (S/PAN/Mg_0.6Ni_0.4O) composite via wet ballmilling. The SEM observation revealed that the composite morphology was drastically changed by the addition of Mg_0.6Ni_0.4O, from smooth bulky particles of S/PAN to rough nanostructured agglomerates with two times the increase in the specific surface area, favouring the reactivity of the composite, and a homogeneous component distribution. Cyclic voltammetry, discharge–charge tests and ac impedance spectroscopy have shown improved conductivity and electrochemical properties of the composite by the addition of Mg_0.6Ni_0.4O, leading to high sulfur utilization and interfacial stabilization in a Li/S cell upon discharge–charge cycling. The cell demonstrated enhanced reversibility, resulting in a discharge capacity of about 1223 mA h g⁻¹ at the second cycle and retained about 100% of this value over 100 cycles. Furthermore, the S/PAN/Mg_0.6Ni_0.4O composite cathode exhibited a good rate capability with discharge capacities of 887, 710 and 445 mA h g⁻¹ at 0.5, 0.7 and 1 C, respectively.

In this work, a novel aqueous rechargeable battery Zn/LiCl-ZnCl2/LiFePO4 has been developed. The electrochemical performance of olivine LiFePO4 positive electrode has been investigated in the structure of this battery. Along with a high (about 100%) coulombic efficiency, this electrode exhibited enhanced cycling performance at various current densities up to 60C with the average operation voltage 1.2V. A capacity of 92mAhg−1 was achieved over 400 cycles at a cycling rate 6C, and exhibited a superior rate capability with the capacities of 72mAhg−1 at 30C and 45mAhg−1 at 60C, respectively. The battery temperature tolerance was first investigated, and it demonstrated a very stable cycling at a wide temperature range from −10°C to 50°C. A cylindrical battery with the capacity of 150mAh was first designed using proposed configuration and successfully operated under 54mA with high efficiency and capacity retention. Zn/LiFePO4 battery offers an exceptionally safe, low cost, long cycling life, and high energy and power density energy storage for large-scale applications