Efficient preparation method of sulfur halide compound solid electrolyte

Abstract

The invention discloses a preparation method of an efficient sulfur halide compound solid electrolyte. The preparation method comprises the following steps: weighing Li2S, P2S5 and X-containing lithium salt according to a required stoichiometric ratio; weighing a grinding medium; the preparation method comprises the following steps: adding raw materials into a vacuum ball milling tank, filling argon into the ball milling tank, and performing primary ball milling in a positive pressure state; vacuumizing and heating the ball milling tank, and carrying out secondary ball milling; cooling the ball-milling tank, filling argon, and carrying out third-time ball-milling to obtain uniformly mixed solid electrolyte precursor slurry; drying the solid electrolyte precursor slurry under the protection of an inert atmosphere; and sintering the dried solid electrolyte precursor at high temperature, cooling, grinding and screening to obtain the sulfur halide compound solid electrolyte with high ionic conductivity. The sulfur halide compound solid electrolyte prepared by the invention has relatively high ionic conductivity and a relatively wide electrochemical window. In addition, compared with a traditional preparation method, the method has the potential of large-scale production.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion batteries, and in particular relates to a method for preparing a sulfur-halogen compound solid-state electrolyte. Background technique [0002] The development of electric vehicles can reduce my country's dependence on foreign oil, improve energy security, and support major national development strategies. However, at this stage, the power batteries are all liquid batteries. The lithium dendrites formed during the electrochemical cycle can easily cause the liquid batteries to fail or even short-circuit, which can seriously cause the car to spontaneously ignite. The solid-state battery can avoid this phenomenon and improve the safety of the battery. In addition, the theoretical energy density of the solid-state battery is greater than that of the existing liquid battery, which is an inevitable trend of future development. However, the preparation and large-scale production of solid electrolyte...

AI Technical Summary

Problems solved by technology

In dry ball milling, the distribution of raw materials is uneven, and it is easy to stick to the inner wall of the ball milling tank and the surface of ball milling beads, and the yield is low; while in wet ball milling, the raw materials do not have enough contact with each other due to the existence of the grinding medium, and the pre-reaction is not thorough enough, so it cannot Obtain the expected crystal phase

The disadvantage of the liquid phase method is that the reaction time is longer, the raw materials are difficult to dissolve, and the ionic conductivity of the obtained solid electrolyte is generally low.

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