Li-In alloy: preparation, properties, wettability of solid electrolytes based on Li7La3Zr2O12

In the presented work, Li-In alloys with 10 and 18 at% Li were obtained. According to scanning electron microscopy, indium is evenly distributed in obtained alloys with different lithium contents. The atomic force microscopy study was used for elastic modulus investigation of Li-In alloys. It was established that obtained alloys are two-phase systems with matrix phase consisting of solid solution (α phase) and inclusions of the LiIn phase (β phase) with individual domain sizes of 0.5–3 μm. The wettability of the solid electrolyte based on Li7La3Zr2O12 with metallic In and Li-In alloy was study by high-temperature optical dilatometry. It was found that metallic indium wets ceramics better than obtained lithium–indium alloys. The symmetric cells with Li and Li-In alloy are assembled and studied. Li-In alloy application as an anode leads to significant reduction in the interface resistance between metallic anode and solid electrolyte from 37 to 0.4 kΩ cm2 at room temperature. The composite solid electrolyte does not degrade in contact with Li-In anode.