Searching Ternary Oxides and Chalcogenides as Positive Electrodes for Calcium Batteries

Abstract

The identification of alternatives to the Lithium-ion battery architecture remains a crucial priority in the diversification of energy storage technologies. Accompanied by the low reduction potential of Ca 2+ /Ca, -2.87 V vs. SHE, metal-anode-based rechargeable Calcium (Ca) batteries appear competitive in terms of energy densities. However, the development of Ca-batteries lacks high-energy density intercalation cathode materials.Using first-principles methodologies, we screen a large chemical space for potential Cabased cathode chemistries, with composition of Ca i TM j Z k , where TM is a 1 st or 2 nd row transition metal and Z is oxygen, sulfur, selenium or tellurium. 10 materials are selected and their Ca intercalation properties are investigated. We identify two previously unreported promising electrode compositions: the post-spinel CaV 2 O 4 and the