Lithium (Li) metal batteries (LMBs) have recently attracted extensive interest in the energy-storage field after silence from the public view for several decades. However, many challenges still need to be overcome before their practical application, especially those that are related to the interfacial instability of Li metal anodes. Here, we reveal for the first time that the thickness of the degradation layer on the metallic Li anode surface shows a linear relationship with Li areal capacity utilization up to 4.0 mAh cm⁻² in a practical LMB system. The increase in Li capacity utilization in each cycle causes variations in the morphology and composition of the degradation layer on the Li anode. Under high Li capacity utilization, the current density for charge (i.e., Li deposition) is identified to be a key factor controlling the corrosion of the Li metal anode. These fundamental findings provide new perspectives for the development of rechargeable LMBs.

几十年来，在人们沉默的情况下，锂金属电池（LMB）最近引起了人们对储能领域的广泛兴趣。然而，在实际应用之前，仍然需要克服许多挑战，特别是与锂金属阳极的界面不稳定性有关的挑战。在此，我们首次揭示了金属锂阳极表面上降解层的厚度与最大面积利用率达到4.0 mAh cm ^-2的锂面利用率成线性关系。在实际的LMB系统中。每个循环中锂容量利用率的增加导致锂阳极上降解层的形态和组成发生变化。在高Li容量利用率下，电荷的电流密度（即Li沉积）被确定为控制Li金属阳极腐蚀的关键因素。这些基本发现为可充电LMB的发展提供了新的视角。