Island-like coating with Pr6O11 nanoparticles enables high-voltage and durable LiNi0.5Mn1.5O4 cathode

Spinel LiNi 0.5 Mn 1.5 O 4 (LNMO) is a promising high-voltage cathode material for next generation lithium-ion batteries. However, its application is limited by severe interfacial side reactions and structural degradation under high-voltage conditions, which lead to poor cycling stability and inferior rate performance. Conventional full-coverage coatings cannot withstand cyclic mechanical stress during charge-discharge processes, easily causing cracks and performance fading. In this work, an island-like coating structure based on Pr 6 O 11 nanoparticles was immobilized on the LNMO surface (Pr 6 O 11 -LNMO). The island-like structure can adapt to volume changes during cycling, inhibit the dissolution of transition metals and slow down electrolyte decomposition. The oxygen vacancies in Pr 6 O 11 enable fast Li + transport, and the Pr 4+ /Pr 3+ valence equilibrium of Pr 6 O 11 can increase the Mn 4+ content in LNMO, thereby alleviating the Jahn-Teller distortion induced by Mn 3+ . In-situ XRD results reveal that faster Li + kinetics and better interfacial stability inhibit the two-phase transition of LNMO and orient it toward a reversible solid-solution reaction. The optimized Pr 6 O 11 -LNMO exhibits superior cycling stability (94.6% capacity retention after 500 cycles at 1C) and excellent rate capability (111.9 mAh g −1 at 20C). This strategy provides a promising solution for preparing durable high-voltage LNMO cathodes and facilitates the advancement of lithium-ion batteries with high energy density.