“…During the initial cycle, the capacity is primarily provided by redox couples, such as Ni 2+ /Ni 3+ , Ni 3+ /Ni 4+ , and O 2− /O − , but the release of lattice oxygen will activate lower voltage redox couples, such as Mn 3+ /Mn 4+ and Co 2+ /Co 3+ , resulting in a continuous decrease in the average valence state of transition metal ions and then accelerate the voltage decay [52]. Meanwhile, a decrease in the Mn element's valence state stimulates the Jahn-Teller effect, which intensifies Mn element dissolution [113,114,117]. Moreover, triggering anionic redox reactions reduces the formation energy and diffusion barriers of oxygen vacancies, leading to nanohole formation and crystal structure transformations [115,118].…”