A Coaxial-Interweaved Hybrid Lithium Metal Anode for Long-Lifespan Lithium Metal Batteries

摘要

Lithium (Li) metal is one of the most promising anode materials to construct next-generation rechargeable batteries owing to its ultrahigh theoretical capacity and the lowest electrochemical potential. Unfortunately, practical application of Li metal batteries is severely hindered by short lifespan and safety concerns caused by Li dendrite growth during cycling. Herein, a coaxial-interweaved hybrid Li metal anode is proposed for dendrite inhibition that significantly improves the cycling stability of Li metal batteries. The hybrid Li metal anode is fabricated by Li composition into a 3D interweaved scaffold, where each fiber of the interwoven scaffold is composed of a conductive skeleton and a coaxial lithiophilic layer modified on the surface. The coaxial-interweaved structure endows the hybrid anode with favored Li affinity to guide uniform Li deposition, sufficient channels for ion transportation and electron conduction, and enhanced stability during Li plating and stripping. Consequently, the hybrid Li metal anode affords high Coulombic efficiency over 98.5% for 750 cycles with dendrite-free morphologies in half cells and improved capacity retention of 80.1% after 100 cycles in LiFePO4 full cells. The innovative coaxial-interweaved hybrid Li metal anode demonstrates multiscale design strategy from lithiophilic modification to scaffold construction and promises the prospect of Li metal batteries for future applications.