Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300072, China.
Department of Mechanicals, Dalian University of Technology , Dalian 116024, China.
Nano Lett. 2017 Sep 13;17(9):5862-5868. doi: 10.1021/acs.nanolett.7b03185. Epub 2017 Aug 14.
Na-based batteries are proposed as promising energy storage candidates for beyond Li-ion technology due to the higher natural earth of Na metal. For its high capacity and low potential, Na metal may carve itself a niche when directly used as anodes. Similar to or even more problematic than Li, however, uneven plating/stripping of Na leads to dendrite formation. As the plating substrates, current collectors have a paramount influence on the Na plating/stripping behaviors. Here we propose porous Al current collectors as the plating substrate to suppress Na dendrites. Al does not alloy with Na. It is advantageous over Cu current collectors in terms of cost and weight. The interconnected porous structure can increase available surface for Na to nucleate and decrease the Na flux distribution, leading to homogeneous plating. The Na metal anodes can run for over 1000 cycles on porous Al with a low and stable voltage hysteresis and their average plating/stripping Coulombic efficiency was above 99.9%, which is greatly improved compared to planar Al. We used the porous Al for Na-O, Na-NaV(PO) cells with low Na amount and anode free Na-TiS batteries and anticipate that using this strategy can be combined with further electrolyte and cathodes to develop high performance Na-based batteries.
基于钠的电池因其较高的天然钠金属含量而被认为是有前途的超越锂离子技术的储能候选物。由于其高容量和低电势，钠金属在直接用作阳极时可能会有自己的优势。然而，与锂相似甚至更具挑战性的是，钠的不均匀电镀/剥离会导致枝晶的形成。作为电镀基底，集流器对钠的电镀/剥离行为有至关重要的影响。在这里，我们提出了多孔铝集流器作为电镀基底来抑制钠枝晶的形成。铝不与钠形成合金。它在成本和重量方面优于铜集流器。互连的多孔结构可以增加钠成核的可用表面积，并减少钠通量分布，从而实现均匀电镀。多孔铝上的钠金属阳极可以运行超过 1000 个循环，具有低而稳定的电压滞后，其平均电镀/剥离库仑效率超过 99.9%，与平面铝相比有了很大的提高。我们将多孔铝用于低钠量的 Na-O、Na-NaV(PO) 电池和无阳极的 Na-TiS 电池，并预计使用这种策略可以与进一步的电解质和阴极相结合，以开发高性能的钠基电池。
