The invention relates to the technical field of
solid-state electrolytes, and discloses a high-ionic-
conductivity solid-state
electrolyte, a preparation method thereof and a
solid-state battery. The preparation method comprises the following steps: mixing
lithium sulfide,
lithium chloride,
lithium oxide,
phosphorus pentasulfide and
boron nitride in an
inert atmosphere to obtain a mixture; carrying out ball milling on the mixture to obtain precursor
powder; and
sintering the precursor
powder, and dispersing the sintered precursor
powder to obtain the high-ionic-
conductivity solid
electrolyte. The
boron element, the
nitrogen element and the
oxygen element are introduced into a lithium
phosphorus sulfur chlorine system as
doping elements, lattice parameters of LPSC are changed through the
boron element, the rotation rate of a PS4 / BS4
tetrahedron is enhanced, and a lithium
ion diffusion channel is optimized, so that the lithium
ion transition
activation energy of the
electrolyte is reduced, the migration rate of lithium ions is increased, and the performance of the electrolyte is improved. Therefore, the solid electrolyte has high
ionic conductivity. The introduced
nitrogen element and
oxygen element can interact with atoms such as
sulfur and
phosphorus, the
electron cloud distribution of anion groups is adjusted, the
interaction energy of lithium ions and the anion groups is reduced, the lithium
ion transmission performance is further improved, and the electrochemical stability of the anion framework is enhanced. This makes it possible to increase the
energy density of an all-solid-state battery when used in a solid-state battery.