Now a days, solid-state lithium-metal batteries are attracting interest as potential replacement for conventional Li-ion batteries Replacing the organic liquid-based electrolyte with a lithium-ion conducting solid-state electrolyte (SSE) reduces safety issues, release of toxic gases, risk of thermal runaway and short-circuiting. Among the different types of oxide-based inorganic solid-state electrolyte, the NASICON-structure, lithium aluminium titanium phosphate (Li(1+x)AlxTi(2-x)(PO4)3, LATP) is considered as one of the most promising SSEs to be used as catholyte. However, poor physical contact and high charge transfer resistance at the cathode/electrolyte interface are the major challenges in the development of for the quest of hybrid solid state lithium metal batteries. Moreover, the non-homogeneous lithium-ion transport and high tortuosity in thick electrodes impedes the long-term cyclic performance of the batteries and fast capacity fading. We design the preparation of composite cathode my incorporating the different amount of lithium aluminium titanium phosphate (Li(1+x)AlxTi(2-x)(PO4)3, LATP) into the NMC cathode materials by using simple and easily up-scalable mechanical mixing method. This helps in enhancing good ionic conduction in thick electrodes by filling the porosity of the thick electrodes. Study the effect of LATP amount on the electrochemical properties of the cathodes. The electrochemical performance of the composite cathode was tested using an in-situ polymerized electrolyte. As a preliminary measurement the electrochemical performance of the composite cathode was tested using the convectional liquid electrolyte (1 M LiPF6 in EC: DEC w/w). The cell impedance using the liquid electrolyte shows comparable result and shows the negligible impact of LATP in the composite cathode howver and electrochemical cell measurement using the in-situ polymerized electrolyte, a substantial impact of LATP amount on cell impedance could be observed. Cell impedance decreased when increasing the LATP amount in the composite cathode, indicating improved ion conduction. The initial capacity of the cathode decreases when introducing LATP, suggesting insufficient filling of the remaining porosity in case of p-DOL electrolyte. Capacity fading over cycling is observed in all cases, suggesting the p-DOL composition should be optimized.
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