All-Solid-State Lithium Battery and Preparation Method Thereof

The present invention discloses a preparation method of an all-solid-state lithium battery based on borohydride/sulfide two-layer fast ion conductors, comprising the steps of: Step 1: cold-pressing a borohydride fast ion conductor and a sulfide fast ion conductor into a two-layer electrolyte; Step 2: mixing a cathode active material, a sulfide fast ion conductor, and a conductive agent according to a ratio to prepare a cathode of the all-solid-state lithium battery, and cold-pressing the cathode onto a side, corresponding to the sulfide fast ion conductor, of the two-layer electrolyte obtained in Step 1; and taking a lithium metal plate as an anode of the all-solid-state lithium battery, and cold-pressing the anode onto a side, corresponding to the borohydride fast ion conductor, of the two-layer electrolyte obtained in Step 1; and Step 3: packaging a material obtained in Step 2 to obtain the all-solid-state lithium battery based on borohydride/sulfide two-layer fast ion conductors. According to the present invention, an all-solid-state battery with high working voltage and good cycle performance is achieved, and the preparation process is simple and has good repeatability, thereby being suitable for large-scale commercial production.