The invention relates to preparation and application of a high-entropy
lithium argyrodite type
sulfide solid electrolyte. The
structural formula of the high-entropy
sulfide electrolyte is Li theta M alpha N beta P1-alpha-beta S 4.5-
lambda X
lambda Y 1.5, wherein theta is more than 5.32 and less than 6.46, alpha is more than or equal to 0.01 and less than 0.32, beta is more than or equal to 0.01 and less than 0.32, alpha + beta is more than 0 and less than or equal to 0.32, and
lambda is more than 0 and less than or equal to 0.5. In the
sulfide solid electrolyte prepared by
doping elements with different physical properties, the introduction of
metal cations can generate additional
lithium vacancies, increase the degree of freedom of
lithium ion migration and improve the
ionic conductivity, and meanwhile, the introduction of soft acid cations can form a stable tetrahedral structure and improve the air stability; the introduction of the inorganic anions can form a stable
interface layer in situ at the lithium negative
electrode, prevent the contact between the electrolyte and the lithium negative
electrode and improve the stability of the negative
electrode interface, and the introduction of the
halogen anions can adjust the disorder degree of internal atoms and increase the configuration entropy of the material, so that the
diffusion energy barrier of lithium ions is reduced, and the
ionic conductivity is improved.