Non-Axial Stress Orbital Interaction Induced Degradation Anisotropy in Layered Electrodes via MEMS chip-based in situ...

The structural degradation remains a critical bottleneck in Mn-based layered cathodes due to strong Mn distortion and dissolution. While internal stresses are always associated with the intrinsic planar instability and are generally believed to exacerbate the octahedral distortion, our non-axial pre-bending strategy reveals a distinct stress-orbital coupling that leads to an anisotropic degradation pathway with enhanced Mn stability. Through MEMS chip-based in situ TEM studies, non-axial stress is found to induce a counteractive lattice distortion that reduces the cooperative Jahn-Teller effect by spatially decoupling axial and equatorial Mn─O bond deformations. As a result, the emergence of degenerate electronic ground states is suppressed, leading to reduced lattice distortion and enhanced kinetic stability. This work establishes a dedicated relationship between non-axial stress and orbital coupling, thereby offering a stress-orbital interaction strategy for designing stable layered cathodes.