Synthetic method for lithium iodide for cell and preparation method for electrolyte of lithium iodide

The invention relates to a synthetic method for lithium iodide for cells and a preparation method for an electrolyte of lithium iodide, belonging to the filed of batteries. The synthetic method for lithium iodide comprises the following steps: using lithium hydroxide or lithium carbonate and hydroiodic acid as raw materials to prepare a crude product of lithium iodide; dissolving the crude product of lithium iodide in an organic solvent in a glove box and adjusting the pH value of the solution to between 1 and 6; carrying out filtering; carrying out reduced pressure distillation for 0.5 to 50 hours; cooling the product of the distillation to normal temperature so as to obtain battery-grade white solid lithium iodide. The organic electrolyte of lithium iodide is obtained by dissolving the synthesized lithium iodide in an organic solvent. The synthesized battery-grade lithium iodide in the invention has a high purity and low moisture, and can be utilized for injection into cells after addition into an organic solvent without dewatering.