Dual regulation of particle size and surface structure of SrVO3 for high volumetric capacity

Abstract

Perovskite SrVO3 stands out as a promising anode material for lithium-ion batteries due to its inherent redox activity, excellent electrical conductivity, and structural adaptability. Despite these advantages, challenges persist, such as in achieving high tap density and volumetric specific capacity. In this study, we overcome these challenges by finely regulating particle size and constructing a tailored surface structure for SrVO3. The implementation of ball milling during the synthesis process proves to be a simple yet highly efficient method for simultaneously tailoring particle size and in-situ creating an amorphous layer on SrVO3 particles. The reduction in particle size not only facilitates enhanced electron and ion transport but also significantly improves the tap density of SrVO3, increasing it from 2.61 to 3.15 g cm−3. The in-situ construction of an amorphous layer introduces a multitude of defects and high valence V5+. These defects serve as active sites for lithium ions, while the V5+ species contribute to increased electron transfer, collectively resulting in a high gravimetric specific capacity. The engineered SrVO3 anode delivers an impressive volumetric capacity of 1134 mAh cm−3 at 0.1 A g−1, surpassing both pristine SrVO3 (733 mAh cm−3) and commercial graphite anode (∼460 mAh cm−3).