Fabrication and Characterization of LiNi1/3Mn1/3Co1/3O2/Li0.6La0.4TiO3/Li4Ti5O12 Full Cell All-Solid-State Thin Film Li-Ion Batteries for Energy Applications

Abstract

Recent days, natural calamities caused by the global warming and climate changes are major concern for the entire globe and there is a pressing need to address such issues to save the mankind from further havoc and devastation. To reduce the carbon emission, countries are shifting dramatically towards renewable sources for their energy needs for their day-to-day life. Li ion batteries are in the forefront of the battle towards the sustainable growth and development due to their high energy density and renewable in nature. In the present case, we report on development of thin film based all-solid-state batteries (ASSB) for energy applications. LiNi1/3Mn1/3Co1/3O2 (NMC), Li0.6La0.4TiO3 (LLTO) and Li4Ti5O12 (LTO) materials are employed as a cathode, solid electrolyte and anode layers for fabricating a full cell all-solid-state thin film batteries. All the layers are fabricated employing RF sputtering technique. Before fabricating the full cell, individual layers are fabricated and their electrochemical and/or ionic conductivity properties are explored. Li0.6La0.4TiO3 solid electrolyte thin films are seen to exhibit room temperature in-plane ionic conductivity in the order of 10-3 S/cm. NMC thin film with the thickness of 100 nm exhibits specific capacity of 91 µAh/cm2 and the redox peaks at 3.8 V and 3.5 V. LTO anode thin films shows the specific capacity close to 100 mAh/cm2and the redox peaks around 1.5 V. XRD pattern of NMC/LLTO/LTO full cell shows the diffraction peaks corresponding to all the three layers. Cross-sectional scanning electron microscope (SEM) image indicates the uniform coating and presence of all the layers. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) along with the energy dispersive X-ray is employed to image the cross-sectional details and the elements present in each layer of the full cell all-solid-state thin film battery. Impedance spectroscopy was employed to calculate the total conductivity of the fabricated full cell. Obtained results indicates that the full cell NMC/LLTO/LTO thin film batteries can be fabricated employing a sputtering technique for the energy applications. Figure 1