Optimizing Disordered Rock Salt Cathodes by Solid-State Synthesis and Design of Experiments for Enhanced Battery Performance

Abstract

Aiming at discovering new positive electrode materials with superior electrochemical performance for application in lithium-ion batteries, this work focuses on the design of fluorine-free, manganese-rich disordered rock salt (DRX) cathodes. Samples with a starting composition of Li_1.1Mn_0.8Ti_0.1O₂ are successfully prepared by facile solid-state synthesis and further optimized through a design of experiments approach. Several key factors are examined, including carbon type and content as well as lithium (precursor) excess. The tailored DRX/carbon composites, using either graphite or multiwalled nanotubes, are capable of delivering specific capacities of up to 190 mAh g⁻¹ and exhibit high cycling stability, with the capacity retention being greater than 90% after 100 cycles. This study emphasizes the importance of screening key factors in developing next-generation battery materials.