Solid-state unit cell, preparation method thereof and multilayer solid-state battery

The invention provides a solid-state unit cell, a preparation method thereof and a multilayer solid-state battery. The preparation method comprises the following steps: S1, preparing a double-sided negative plate, and performing insulation treatment between a negative tab of the double-sided negative plate and a negative plate material by using an insulating tape; s2, respectively pasting solid electrolyte membranes on the double-sided negative plate by a transfer printing method; s3, preparing a single-sided positive plate, and respectively attaching the positive plate to the solid electrolyte membrane to obtain an inner cell; s4, stainless steel foils are attached to the outer sides of the two positive plates of the inner battery cell, the size of the stainless steel foils is larger than that of the largest electrode plate, the peripheries of the stainless steel foils are sealed through sealing adhesive tape, packaging is completed, and a packaged battery cell is obtained; and S5, carrying out isostatic pre