Intergrating Hollow Multishelled Structure and High Entropy Engineering toward Enhanced Mechano-Electrochemical Properties in Lithium Battery

Hollow multishelled structures (HoMSs) are attracting great interest in lithium-ion batteries as the conversion anodes, owing to their superior buffering effect and mechanical stability. Given the synthetic challenges, especially elemental diffusion barrier in the multimetal combinations, this complex structure design has been realized in low- and medium-entropy compounds so far. It means that poor reaction reversibility and low intrinsic conductivity remain largely unresolved. Here, a hollow multishelled (LiFeZnNiCoMn)3O4 high entropy oxide (HEO) is developed through integrating molecule and microstructure engineering. As expected, the HoMS design exhibits significant targeting functionality, yielding satisfactory structure and cycling stability. Meanwhile, the abundant oxygen defects and optimized electronic structure of HEO accelerate the lithiation kinetics, while the retention of the parent lattice matrix enables reversible lithium storage, which is validated by rigorous in situ tests and theoretical simulations. Benefiting from these combined properties, such hollow multishelled HEO anode can deliver a specific capacity of 967 mAh g-1 (89% capacity retention) after 500 cycles at 0.5 A g-1. The synergistic lattice and volume stability showcased in this work holds great promise in guiding the material innovations for the next-generation energy storage devices. A high entropy oxide (LiFeZnNiCoMn)3O4 hollow multishelled sphere (HEO-HoMS) with multiple electroactive elements is successfully developed. Benefiting from the delicate cocontrol from molecule to microstructure, HEO-HoMS provides impressively high specific capacity and long life span for lithium storage. This work may inspire more thoughts on rational multiscale design of conversion-type electrodes. image