In situ constructing lithiophilic and Ion/Electron Dual-Regulated current collector for highly stable lithium metal batteries

The uncontrollable dendrite growth is the most critical barrier that hinders the practical applications of Li metal anodes. Herein, a novel lithiophilic and mixed ion/electron conductive current collector is constructed via a facile in-situ activation process of nickel sulfide on the Nickel foam (NF). Such current collector exhibits excellent lithiophilicity, high Li+ diffusion coefficient and electron conductivity due to its unique vertical-aligned and interconnected arrays consisting of lithium sulfide and nickel on NF skeleton. Especially, the mixed ion/electron conductive arrays not only effectively regulate the ionic flux and electric field, but also provide continuous pathways for the fast transportation of both the Li+ and electron. As a result, the growth of Li dendrites is suppressed. Moreover, full cells with low Negative/positive (N/P) ratio exhibit superior cycling stability, high-capacity retention and outstanding rate performance. Typically, full cells pairing with LiFePO4 (LFP) cathodes with a N/P ratio of 6.3 show long-term cycling for over 700 and 350 cycles at high rates of 5C and 10C, delivering ultrahigh capacity retentions of over 95.7% and 86.4%, respectively. Even with an ultralow N/P ratio of 1.2 with LFP loading of 2.45 mAh cm−2, the full cell still shows excellent cycling stability for over 130 cycles. This work sheds new light on the development of dendrite-free Li metal anodes for high-performance Li metal batteries with lithiophilic and ion/electron dual-regulated current collector.