三维铜基集流体的构筑及在锂金属电池中的应用

Construction of 3D Copper-Based Collector and Its Application in Lithium Metal Batteries

锂金属因其具有超高比容量(3860 mAh·g^(-1))以及较低的氧化还原电势(-3.04 V vs标准氢电极),被认为是下一代高能量密度二次电池的理想负极材料。然而“无宿主”的金属锂在金属/电解液界面层进行沉积/剥离,不可避免地会生长枝晶,不仅使电极表面电流分布不均,同时可能会刺穿电池隔膜而导致电池短路。通过构造三维集流体/锂金属复合负极可以有效调控锂沉积行为并抑制枝晶生长,从而提升电池的库仑效率、循环寿命以及倍率性能,该领域近年来一直都是研究的热点。本文首先总结了基于三维集流体抑制锂枝晶的相关原理和模型;其次针对用于负极的铜基集流体,根据构成三维结构基底单元的维度,总结了三维铜基集流体的制备方法及其在锂金属负极保护方面的应用;最后,对三维集流体构造复合锂负极进行了总结和展望。

Lithium metal is considered as an ideal anode for next generation high energy density secondary batteries due to its high specific capacity(3860 mAh·g^(-1))and low redox potential(-3.04 V vs standard hydrogen electrode).However,the"hostless"lithium metal is plated/stripped at the metal/electrolyte interface layer,inevitably growing dendrites and resulting in uneven distribution of current on the surface of lithium metal,which may puncture the battery separator and cause short circuit of the battery.In practical applications,by constructing three-dimensional current collector/lithium metal composite anode,the lithium deposition behavior can be effectively regulated and the dendrite can be suppressed,which further enhances the Coulombic efficiency,cycling life and rate performance.The research on this aspect has become a hot topic in recent years.In this review,firstly,the related principles and models of the suppression of lithium dendrite based on 3 D current collector are summarized.Secondly,for the copper-based current collector,the preparation methods of 3 D current collectors and their application in the protection of lithium metal anode are systematically summarized according to the dimension of substrate units.Finally,we summarize and outlook on the composite lithium anode constructed by 3 D current collectors.