Research On Corrosion Behavior Of Aluminum Nitride In Lithium Vapor

The liquid metal battery is a new type of energy storage battery technology and it is very promising for business due to its low cost,large capacity,high efficiency and long service life.But both the high operating temperature and reactivity of the electrodes render insulators and sealed parts heavy corrosion which can affect the performance of the battery in various degrees and further lead to a shortened service life.This article proves that AlN ceramics can be used as potential insulated ceramic materials for ceramic components to improve the service life of liquid metal batteries.In this paper,both yttrium and zirconium-doped aluminum nitride ceramics are investigated in high-temperature lithium vapor and molten metal lithium environments.It is found that the former has obvious changes in color and morphology,while the latter exhibits good corrosion resistance.Meanwhile,the corrosion behavior and possible failure mechanism of aluminum nitride ceramic in both lithium vapor and molten lithium have been investigated using X-ray diffraction、scanning electron microscope、X-ray photoelectron spectroscopy and auger electron spectroscopy technology.It is showed in research that when Y-doped AlN is corroded in lithium vapor,aluminum-lithium compounds and yttrium-aluminum compounds will be generated at the trigeminal grain boundaries and prevent the diffusion of lithium along the grain boundaries,which causing the lithium concentrated and weakening the crystals.While in the metal lithium,the lithium will enter the ceramic through the defective parts on the surface of the sample and diffuse along the grain boundaries,gradually wrapping the aluminum nitride grains together.Zr-doped AlN has better corrosion resistance in metallic lithium because of Zr element-related compounds having better compatibility with lithium.Lithium corrosion on aluminum nitride is carried in different environment for the first time and effect in comparison were made in this thesis.Meanwhile,it is pointed that appropriate doping techniques can effectively enhance the corrosion resistance of aluminum nitride ceramics in lithium vapor and molten lithium,which has reference significance for follow-up related research.