6 - Battery cathodes for lithium-ion batteries with liquid and solid-state electrolytes

Abstract

Numerous intercalation cathode materials, initially developed for lithium-ion batteries with liquid electrolytes, have been synthesized and tested over time. The most important parameters include lithium-ion storage capacity, operating voltage, and current density. With the ultimate goal of performance improvement, different metal oxides in the form of solid solutions or nanocomposites have been engineered. Among them, layered lithium-based metal oxides with transition metals, such as nickel, cobalt, manganese, and iron, have been broadly studied in terms of their chemical, electrochemical, physical, and mechanical properties. However, a number of challenges, such as voltage and capacity decay with cycling, irreversible capacity loss, insufficient rate capability, and oxygen gas evolution, still exist. In solid-state batteries, these problems are further complicated due to the absence of liquid electrolyte that provides high lithium-ion conductivity and conduction pathways within porous cathode structures. On the contrary to cathode materials in batteries with liquid electrolytes, all-solid-state battery cathodes require even more efforts regarding novel architectural designs that allow for sufficiently high ionic and electronic conductivity within the bulk of the lithium-ion storage metal oxides and at the interfaces with solid-state electrolytes.