Novel glass-ceramic ion conducting electrolytes for safe, high-energy solid-state secondary batteries
External reference persons Giuseppe Antonio Elia, Sofia Saffirio
Thesis type EXPERIMENTAL APPLIED
Description Renewable energy sources (RESs) represent a striking energy supply that can help reducing the environmental impact of electricity production. However, some of them (e.g. solar or wind) are intermittent by nature. To overcome this relevant issue, energy storage is an efficient way to maintain a constant electric supply. Batteries used as electrochemical storage represent one of the best solutions. Solid-state-batteries (SSBs) are devices relying on solid electrolytes to store energy. Their integration to systems based on RESs represent an effective way to overcome their intermittence. This solution is progressively replacing the commonly used liquid electrolytes since they suffer from low thermal stability being volatile and may cause serious safety issues. Furthermore, SSBs offer better cycling stability and lifetime at lower processing costs. However, SSBs have some intrinsic drawbacks, which include low ionic conductivity and instability at the interface with the electrode materials. Recently, solid electrolytes with a NASICON) structure have been widely investigated by the scientific community, due to their electrochemical stability and appreciable ionic conductivity. In this context, the aim of the present Master Degree Thesis is to develop and characterize a new NASICON composition, based on the LAGP (Lithium Aluminum Germanium Phosphate) glass ceramic electrolyte material for secondary solid-state alkali metal ion batteries. The produced glass material will be physico-chemically and thermally characterized by Differential Thermal Analysis (DTA) and Heating Stage Microscopy (HSM) to assess the sinter-crystallization behavior. X-ray Diffraction (XRD) analysis will allow to study the chemical composition and crystal structure of the samples, thus understanding which phases are present. Scanning Electron Microscope (SEM) will be used to understand the morphology of the glass-ceramic samples, their densification and their conductivity. To determine the ionic conductivity of gold-sputtered samples, Electrochemical Impedance Spectroscopy (EIS) will be carried out. All the materials will be then thoroughly electrochemically characterised to evaluate their promising prospects in real cell configuration.
Deadline 16/05/2023 PROPONI LA TUA CANDIDATURA