All-solid-state lithium secondary battery containing llzo solid electrolyte and method for preparing same

Abstract

The present invention relates to an all-solid-state lithium secondary battery and a method of manufacturing the same. The all-solid-state lithium secondary battery includes a cathode, an anode, and a composite solid electrolyte layer between the cathode and the anode, wherein first and second LLZOs contained respectively in the cathode and the composite solid electrolyte layer are each independently aluminum-doped or undoped LLZO, and the battery of the invention can exhibit improved discharge capacity and cycle characteristics because both the cathode and the composite solid electrolyte layer contain a conductive polymer, a lithium salt and an inorganic ceramic solid electrolyte. The method of the invention enables the all-solid-state lithium secondary battery to be manufactured in a non-sintering manner, thus reducing manufacturing costs and controlling interfacial reactions between active materials, between solid electrolyte particles, and between an electrolyte and an electrode, thereby further reducing the internal resistance of the battery.