Review—Revealing the Intercrystalline Cracking Mechanism of NCM and Some Regulating Strategies

Nickel-rich cathode has received much attention due to its high energy density, high capacity, low cost and environmental friendliness. The existence of intercrystalline microcracks in NCM seriously affects the structural stability and integrity of the battery crystal surface. Irreversible phase transitions result in changes in lattice parameters, the interface side reactions severely corrode the crystal surface, and secondary particle heterogeneity leads to uneven reactions. Common amorphous microcracks include single crystal, gradient doping, etc. This review first introduced the microcrack mechanism of NCM, and then summarized two solutions: single crystal and gradient doping. Finally, we presented new views and insights, and hope to give enlightenment on the subsequent inhibition of intercrystal microcrack, and construct the reasonable structure of NCM cathode.