Multidentate Chelation of Phytate Suppresses Mn Dissolution and Enhances Structural Stability of Li-Rich Mn-Based...

Mn dissolution remains a primary obstacle limiting the long-term cycling stability of Li-rich Mn-based layered oxides (LRMOs) under high voltage. In this work, we develop a phytate-based multidentate chelation coating that directly addresses this challenge. The phytate molecule, rich in phosphate groups, simultaneously binds to Mn2+ ions via multiple coordination sites, effectively sequestering them and preventing their loss into the electrolyte. This chelation-driven protection not only preserves the structural integrity of the layered framework but also suppresses interfacial side reactions. Consequently, the phytate-modified LRMOs deliver a high capacity retention of 97.24% after 300 cycles at 1C, along with a substantially improved rate capability (160.2 mAh g-1 at 10C). Notably, voltage decay is dramatically reduced, and the cathode maintains a well-ordered layered structure even after prolonged cycling. This study highlights the effectiveness of multidentate chelation as a simple yet robust strategy to mitigate Mn dissolution, offering a promising route to enable high-voltage operation of LRMOs for advanced lithium-ion batteries.