Oxides composed of an oxygen framework and interstitial cations are promising cathode materials for lithium-ion batteries. However, the instability of the oxygen framework under harsh operating conditions results in fast battery capacity decay, due to the weak orbital interactions between cations and oxygen (mainly 3d-2p interaction). Here, a robust and endurable oxygen framework is created by introducing strong 4s-2p orbital hybridization into the structure using LiNi0.5 Mn1.5 O4 oxide as an example. The modified oxide delivers extraordinarily stable battery performance, achieving 71.4 % capacity retention after 2000 cycles at 1 C. This work shows that an orbital-level understanding can be leveraged to engineer high structural stability of the anion oxygen framework of oxides. Moreover, the similarity of the oxygen lattice between oxide electrodes makes this approach extendable to other electrodes, with orbital-focused engineering a new avenue for the fundamental modification of battery materials.
Keywords: 4s-2p Orbital Hybridization; Lithium-Ion Batteries; Orbital Modification; Oxygen Framework; Spinel Oxides.
© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.