Electron-ion confinement enabled by 3D Cu framework and lithiophilic Li-Si alloy for high-performance lithium metal batteries

Electron-ion confinement enabled by 3D Cu and Li-Si alloy for lithium metal batteries. • Symmetric cells sustain 4.0 mA/cm 2 with ultralow polarization over 1200 h lifespan. • NCM811 full cells retain 80.70% capacity after 500 cycles at 2C with high loading. • The lithiophilic Li-Si alloy guides uniform Li + flux suppressing dendrite growth. • Pouch cells achieve 83.87% retention after 300 cycles validating practical scalability. Lithium metal batteries with ultrahigh energy density are promising for next-generation energy storage, but their practical deployment are severely hindered by uncontrolled dendrite growth and extreme volumetric instability. Here, we propose electron-ion confinement enabled by 3D Cu framework and lithiophilic Li-Si alloy (3D-LS) for high-performance lithium-metal batteries. A new-type composite anode based on commercial 3D Cu framework and lithiophilic Li-Si alloy is successfully designed and produced via a facile calendering process, which enables electron-ion confinement to suppress dendrite proliferation and mitigate volume expansion-induced stress. 3D conductive Cu framework establishes continuous electronic transmission pathways, while lithiophilic Li-Si alloy regulates uniform Li + flux distribution, synergistically constructing a robust electron-ion confinement structure. Symmetric cell with 3D-LS anode exhibits ultra-long cycling stability over 1200 h at 0.2 mA/cm 2 and maintain robust performance at 4.0 mA/cm 2 . When assembled with industrialized LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathode, full cell retains 80.70% capacity after 500 cycles at 2C, with pouch-cell prototypes further validate its practical scalability. These findings provide a universal electron-ion confinement route to develop ultrastable high-energy-density lithium-metal batteries. Download: Download high-res image (155KB) Download: Download full-size image