Redox Shuttle Enhanced Ion Transport and Cycling Stability of Self‐Healing Electrodes for Direct Lithium Extraction

ABSTRACT Direct lithium extraction using LiMn 2 O 4 spinel suffers from structural instability and capacity fading due to Mn dissolution and Jahn–Teller distortion. Inspired by redox shuttle chemistry, this work presents a dynamic valence‐state engineering strategy utilizing redox‐active Cr 3+ /Cr 4+ , Ni 2+ /Ni 3+ , and Co 2+ /Co 3+ pairs to stabilize the spinel framework. Among these, the Co 2+ /Co 3+ pair functions as an active “electronic buffer pool,” enabling redox‐mediated stabilization that mitigates lattice instabilities during operation. In situ Raman spectroscopy provides spectroscopic evidence of the reversible Co‐O redox dynamics, suggesting possible redox interactions between Co and Mn species (Co 3+ + Mn 2+ → Co 2+ + Mn 3+ ) that help regulate the local electronic environment prior to structural degradation. The optimized LiCo 1.0 Mn 1.0 O 4 electrode achieves a remarkable 75.52% capacity retention over 500 cycles (vs. 14.26% for pristine LiMn 2 O 4 ) in authentic salt lake brine, while suppressing Mn dissolution by 92.3%. Beyond electrochemical superiority, techno‐economic analysis and life‐cycle assessment (TEA/LCA) suggest that this “self‐healing” architecture reduces chemical remediation costs and environmental footprints, aligning with Green Chemistry principles. This redox‐mediated stabilization offers a promising strategy for engineering durable spinel electrodes for sustainable lithium recovery from brines, paving the way for next‐generation selective extraction systems.