Synthesis and Characterization of solid electrolyte and electrode material for all-solid state Li batteries.

Abstract

Researches are being done constantly in Lithium-ion battery to improve its properties like the capacity, stability and rate. Electrolytes are being studied over the years to enhance the properties of batteries. Solid-state electrolytes were discovered which paved way to a more safe, compact and cost-efficient battery. Li7La3Zr2O12 (LLZO) is a garnet type oxide electrolyte having high conductivity. The properties of LLZO were improved by incorporating or doping various elements on them. Doping with the elements like Ga, Al etc. helps in developing a cubic phase in them which has high conductivity. Here, Aluminium is doped on LLZO to develop a cubic phase. Chemical and physical characterizations were done to observe the morphology, crystallinity and the phase formed. Three different polymer solutions were made using PVA, PVP and PVA+PVP, electrospun and pyrolyzed. The characterizations like XRD, FESEM, TEM and Raman spectroscopy were performed on respective samples. The samples were used in making three respective electrodes and fabricated into Lithium-ion coin cells. Charge- discharge measurements were conducted on the coin cells to study their electrochemical properties. Based on the properties, the material can be chosen to be used in electrodes. The Al-doped LLZO and any of the pyrolyzed carbon fibre chosen by its chemical and electrochemical properties can be used in a battery by altering its properties by various methods.