Li metal anodes attract intensive attention due to their high specific capacity, low density and the lowest electrochemical potential. However, inferior coulombic efficiency (CE) and safety hazards induced by uncontrollable Li dendrite growth are main obstacles against the commercialization of Li metal batteries (LMBs). Herein, we demonstrate that the polyacrylonitrile fiber/polyimide sphere (PAN fiber/PI sphere) double-layer coating can serve as an interfacial functional layer to guide uniform Li deposition and inhibit the formation of Li dendrites. Owing to polar groups and regularly arranged PI spheres of the coating layer, Li||PAN/PI@Cu cells display high coulombic efficiency and long cycle life at a current density of 1 mA cm⁻², maintaining an average CE of ∼98.5% after 400 cycles with a deposition capacity of 1 mA h cm⁻².

中文翻译：

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PAN / PI功能性双层涂层，用于无枝晶的锂金属阳极

锂金属阳极由于其高比容量，低密度和最低电化学势而引起了广泛的关注。然而，由于锂枝晶生长不受控制而导致的库仑效率（CE）较低和安全隐患是阻碍锂金属电池（LMB）商业化的主要障碍。本文中，我们证明了聚丙烯腈纤维/聚酰亚胺球（PAN纤维/ PI球）双层涂层可以用作界面功能层，以引导均匀的Li沉积并抑制Li树突的形成。由于极性基团和涂层的有规则排列的PI球，Li || PAN / PI @ Cu电池在1 mA cm ^-2的电流密度下显示出高库仑效率和长循环寿命，在400次循环后，平均CE维持在〜98.5％，沉积能力为1 mA h cm ^-2。