Preparation and characterization of PVDF-HFP composite membrane with magnesium borate reinforcement as a separator for lithium ion batteries by electro-spi̇nni̇ng method

The effective utilization of boron resources in our country and the development of production technologies are of great importance. In this study, boron and magnesium compounds, which are increasingly used in industrial applications, were synthesized in fiber form, and it was anticipated that they would enhance the mechanical strength in composite materials. The aim was to improve the thermal and mechanical properties through the use of Magnesium Borate-reinforced nanofiber-composite material in combination with PVDF-HFP for the production of separators in Lithium Ion batteries. 3 Different films consisting of pure PVDF-HFP, 2.5% Magnesium 97.5% PVDF-HFP, 5% Magnesium Borate 95% PVDF-HFP were formed into DMF/Acetone solvent.Scanning Electron Microscopy (SEM), X-ray diffraction(XRD) and battery tests were performed to examine the mechanical, morphological, crystallographic structure of PVDF-HFP/Magnesium Borate solutions prepared in different ratios in fiber structure and their properties in battery structure. As a result of SEM images, the addition of Magnesium Borate to a 5% PVDF-HFP solution by weight in DMF/Acetone caused an increase in fiber diameter. It is also vaguely seen in the SEM image that a beaded fiber structure can be formed to a greater extent. Reducing the Magnesium Borate additive by increasing the amount of PVDF-HFP in the solution (2.5% by weight) stabilizes the electroweak jet by reducing the viscosity and has led to the formation of a more homogeneous structure compared to the 5% concentration of bead-free nanofiber formation.The presence of the weight percentage of pure PVDF-HFP has been shown to reduce the diameter of nanofibers. CV (Cyclic voltammetry) tests were performed on the prepared batteries and the reduction and oxidation peaks of the batteries were determined.