An Yongling, Pei Zhihao, Luan Deyan, Lou Xiong Wen David
Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong, 999077, China.
Sci Adv. 2025 Aug 22;11(34):eadx7124. doi: 10.1126/sciadv.adx7124. Epub 2025 Aug 20.
Anode-free Na batteries offer the highest possible energy density but suffer from rapid capacity decay resulting mainly from the formation of Na dendrites and large volume change. Here, we design a functionalized porous Al current collector created through template-free electrodeposition and physical separation methods to modulate Na growth behavior. The controlled porous architecture, featuring interconnected ligament-channel networks, reduces structural stress and inhibits dendritic Na formation by lowering local current density and uniformizing ion flux. In addition, the abundant sodiophilic active sites boost reaction kinetics, decrease Na nucleation barrier, and subsequently manipulate homogeneous Na nucleation. Consequently, the porous Al host exhibits high reversibility of dendrite-free Na plating/stripping behavior. A proof-of-concept 4.3 V-class pouch cell achieves an energy density of up to 420.4 watt-hours per kilogram and stable cycling performance with 84.9% capacity retention over 100 cycles under anode-free conditions, providing a pathway for the design of anode-free Na batteries for practical applications.
无阳极钠电池具有可能的最高能量密度，但主要由于钠枝晶的形成和大体积变化而遭受快速的容量衰减。在此，我们设计了一种通过无模板电沉积和物理分离方法制备的功能化多孔铝集流体，以调节钠的生长行为。具有相互连接的韧带-通道网络的可控多孔结构，通过降低局部电流密度和使离子通量均匀化来降低结构应力并抑制枝晶钠的形成。此外，丰富的亲钠活性位点促进反应动力学，降低钠成核势垒，并随后控制均匀的钠成核。因此，多孔铝主体表现出无枝晶钠电镀/剥离行为的高可逆性。一个概念验证的4.3 V级软包电池在无阳极条件下实现了高达420.4瓦时/千克的能量密度和稳定的循环性能，在100次循环中容量保持率为84.9%，为设计用于实际应用的无阳极钠电池提供了一条途径。
