POTASSIUM-INTERCALATED MANGANESE DIOXIDE AS LITHIUM-ION BATTERY CATHODES: A DENSITY FUNCTIONAL THEORY STUDY

Abstract

It is obvious to harness the intermittent renewable energy resources, energy storage applications, such as a lithium-ion battery, are very important. α‒type MnO₂ is considered as an attractive cathode material for lithium-ion battery due to its relatively large (2 × 2) tunnel structure, remarkable discharge capacity, low cost, and environmental benignity. However, low intrinsic electronic conductivity of α‒type MnO₂ limits its full utilization as a cathode for a lithium-ion battery. Therefore, studies to enhance the α‒type MnO₂ properties are undoubted of great interest. While previous computational studies have been focused on pristine α‒type MnO₂, in the present report, we present the theoretical research on potassium-intercalated α‒type MnO₂ using first principle Density Functional Theory calculations for the first time. Our results showed that potassium-intercalated α‒type MnO₂ improved the electronic conductivity which beneficial for energy storage application. The structural transformation of potassium-intercalated α‒type MnO₂ upon lithium insertion are also discussed. Our results may open the avenue for further utilization of potassium-intercalated α‒type MnO₂ materials for not only the lithium-ion battery but also other type energy storage systems.