Toward dendrite-free and fast-charging lithium metal batteries: interfacial engineering of 3D ZnO/ZnSe heterostructural lithium hosts
Lithium metal anodes (LMAs) offer a theoretical capacity of 3860 mAh g−1 and a redox potential of −3.04 V vs. SHE, yet uncontrolled dendrite growth and infinite volume expansion during plating/stripping degrade cycling stability, particularly at high current densities. This study introduces a three-dimensional lithiophilic host fabricated by incorporating ZnO/ZnSe heterostructures onto brass fibers (ZnO/ZnSe@Brass). The hierarchical architecture mitigates volume expansion and reduces local current density during lithiation. The uniformly distributed ZnO/ZnSe acts as a lithiophilic skin, promoting smooth and dense Li deposition. In situ formed solid electrolyte interphase (SEI), enriched with Li2Se and Li2O, provides high ionic conductivity and mechanical robustness, accelerating ion transport and charge transfer kinetics. Symmetric cells with the ZnO/ZnSe@Brass host exhibit cycling stability exceeding 10,000 cycles at 20 mA cm−2 and 1 mAh cm−2, and sustain fast charging at an ultra-high current density of 80 mA cm−2. When paired with LiFePO4, full cells deliver >500 cycles at 2 C and superior rate capability. The ZnO/ZnSe@Brass host design offers a viable pathway for advanced LMAs in fast-charging lithium metal batteries.