The Cyclized Polyacrylonitrile Coating Current Collector for Directional Deposition of Lithium Metal Induced by Zn Nanosheets

Abstract

Lithium (Li) with high theoretical specific capacity and being the lightest metal, so Li metal anodes has attracted significant interest all over the world. This study introduces the first application of cyclized polyacrylonitrile (CPAN) coatings on commercial copper foil to modulate the nucleation and growth of Zn, resulting in the development of Cu@CPAN@Zn (CCZ) composite current collectors for Li metal anodes. The phase changes during the CCZ preparation process are investigated, along with the mechanisms by which CPAN influences Zn deposition behavior. Li deposition tests demonstrate that the ionic conductivity and mechanical properties of CPAN facilitate Li deposition within the CPAN layer, while the incorporation of Zn induces the uniform deposition of Li and suppresses Li dendrite growth. Electrochemical evaluations indicate that the CCZ current collector exhibits a lower Li deposition potential and extended cycling life. Notably, the CCZ@Li symmetric cell shows stable cycling for 1200 hours at 0.5 mA cm^-2 and 0.5 mAh cm^-2. These results underscore the promising potential of CCZ composite current collectors for improving the performance of Li metal batteries.