Abstract: Provided are an all-solid-state battery and a preparation method thereof. The all-solid-state battery includes a positive electrode, a negative electrode, and a solid-state electrolyte located between the positive electrode and the negative electrode. The negative electrode includes a first negative electrode and a second negative electrode. The second negative electrode is located on a side of the first negative electrode. The solid-state electrolyte includes a first solid-state electrolyte and a second solid-state electrolyte. The first solid-state electrolyte is located between the positive electrode and the first negative electrode. The second solid-state electrolyte is located between the positive electrode and the second negative electrode. The roughness of the second solid-state electrolyte is greater than the roughness of the first solid-state electrolyte.

Abstract: The present invention provides a lithium ion battery including a lithium ion battery body. The lithium ion battery body includes a positive electrode sheet, a separator, a cushion rubber and a solid-state negative electrode sheet. The positive electrode sheet and the solid-state negative electrode sheet are provided at upper and lower surfaces of the separator. The cushion rubber is located in the positive electrode sheet and the separator. The present invention further provides a method for preparing a lithium ion battery including the preparation of the positive electrode sheet, the preparation of the solid-state negative electrode sheet and the preparation of the cushion rubber.