Because of its high theoretical specific capacity and low reduction potential, Li metal is considered to be key to reaching high energy density in rechargeable batteries. In this context, most of the research has focused on suppressing dendrite formation during Li deposition to improve the cycling reversibility and safety of the batteries. Here, covalent organic framework (COF) film coating on a commercial polypropylene separator is applied as an ion redistributor to eliminate Li dendrites. The COF crystallites consist of ordered nanochannels that hinder the movement of anions while allowing Li-ions to transport across, leading to a high Li-ion transference number of 0.77±0.01. The transport of Li-ions across the COF film can be considered to be analogous to beads passing through a Galton Board, a model that demonstrates a statistical concept of a normal distribution. Thus, an even distribution of Li-ions is obtained at the COF Li metal interface. The controlled Li-ion flux yields a smooth Li metal surface after 1,000 h (500 times) of cycling, leading to a significantly improved cycling stability and reversibility, as demonstrated by Cu||Li half cells, Li||Li symmetric cells, and LiFePO₄||Li full cells. These results suggest that, following the principle of a Galton Board, nanopore insulators such as COF-based materials are effective ion distributors for the different energy storage or conversion systems.

由于其较高的理论比容量和较低的还原电位，因此锂金属被认为是可充电电池达到高能量密度的关键。在这种情况下，大多数研究都集中在抑制锂沉积过程中枝晶的形成，以提高电池的循环可逆性和安全性。在此，将商用聚丙烯隔膜上的共价有机骨架（COF）薄膜涂层用作离子再分布剂，以消除Li树枝状晶体。COF微晶由有序的纳米通道组成，这些通道阻碍了阴离子的移动，同时允许锂离子迁移，从而导致0.77±0.01的高锂离子迁移数。锂离子在COF薄膜上的传输可以被认为类似于通过高尔顿板的珠子，展示正态分布统计概念的模型。因此，在COF Li金属界面处获得锂离子的均匀分布。经控制的Li离子通量在循环1000 h（500次）后产生光滑的Li金属表面，从而导致循环稳定性和可逆性显着提高，如Cu || Li半电池，Li || Li对称电池和磷酸铁锂₄ || Li满电池。这些结果表明，遵循高尔顿板的原理，纳米孔绝缘体（例如基于COF的材料）是用于不同能量存储或转换系统的有效离子分配器。