Stressed during cycling: Electrochemically induced mechanical deformation in Ni-rich cathode materials

The polycrystalline architecture of Ni-rich cathode materials faces complex stresses during electrochemical cycling. Recently in Matter, Wang et al. discussed different modalities of the O3-O1 phase transformation due to electrochemically induced mechanical deformation using aberration-corrected scanning transmission electron microscopy and applying an artificial-intelligence-assisted super-resolution algorithm. The polycrystalline architecture of Ni-rich cathode materials faces complex stresses during electrochemical cycling. Recently in Matter, Wang et al. discussed different modalities of the O3-O1 phase transformation due to electrochemically induced mechanical deformation using aberration-corrected scanning transmission electron microscopy and applying an artificial-intelligence-assisted super-resolution algorithm. Direct observation of chemomechanical stress-induced phase transformation in high-Ni layered cathodes for lithium-ion batteriesWang et al.MatterFebruary 27, 2023In BriefMechanical degradation and phase transformation are two main causes of the failure of battery cathodes. Aided by deep-learning-aided super-resolution imaging, we discover that severe chemomechanical deformation during battery operation triggers phase transformation and the formation of bending bands and kinks in layered oxide cathodes. The failure mechanism uncovers the connection between mechanical degradation and phase transformation in layered oxides, and it provides useful guidance for the development of advanced layered cathodes for next-generation lithium-ion batteries. Full-Text PDF