Abstract Single‐crystal Ni‐rich LiNi 1−x−y Co x Mn y O 2 (NCM) cathodes have garnered widespread attention in the lithium‐ion battery community due to their unique advantages in mechanical performance and their ability to minimize interfacial electrochemical side reactions. The synthesis of single‐crystal materials with monodisperse and appropriate size, minimal lattice defects, and highly ordered structures is the key for high‐performance batteries. However, achieving this goal poses challenges due to the lack of in‐depth understanding regarding specific experimental parameters and the solid reaction mechanism during the synthesis process. In this review, the aim is to provide an in‐depth analysis of the critical process parameters involved in the synthesis and their impact on crystal morphology, structure, and electrochemical performance. Consequently, the first section focuses on the effect of the precursor morphology, lithium salt, atmosphere, and sintering procedure. In the second section, the study delves into an in‐depth discussion of the solid reaction and crystal growth mechanism. Lastly, it is concluded by highlighting the prospects and challenges associated with the synthesis and application of single‐crystal Ni‐rich NCM cathodes.