Advances in the application of first principles calculations to phosphate-based NASICON battery materials

Abstract

Sodium-ion batteries are a promising area of research, and phosphate-based sodium superionic conductor (NASICON) materials have received significant attention from researchers due to their high structural stability and ionic conductivity. First principles calculations have been employed to facilitate the research process. This paper introduces the application of first principles calculations in the study of battery materials. It reviews the research progress of the application of first principles calculations in phosphate-based NASICON structured cathode, anode and electrolyte materials, which mainly include the intrinsic properties of the materials and the study of ionic doping modification of some of the materials. It is demonstrated that NASICON materials exhibit excellent structural stability, an appropriate working voltage (approximately 2–4.2 V for cathode materials and below 2 V for anode materials) and an exceptional sodium ion transport performance (Na⁺ migration barrier less than 1 eV), which collectively render them highly promising for application. However, the poor electronic conductivity (mostly semiconductor materials, with a band gap of 2–3 eV or so) limits the performance of the material. Ion doping can improve the electronic conductivity of the material to a certain extent, but the NASICON battery materials still cannot be compared with the current commercial lithium-ion battery materials. Consequently, multiple ion doping and conductive material modification will be some of the future research directions. As computers and computing software progress, first principles calculations could eventually become the standard approach for studying battery materials. This strategy might make it more straightforward to select the best battery materials and modification methods while including experimental testing to enhance the phosphate-based NASICON materials' overall performance and develop new battery materials.