Porous conductive interlayer for dendrite-free lithium metal battery

Lithium (Li) metal, possessing ultrahigh theoretical capacity and the lowest electrode potential, is regarded as a promising new generation anode material. However, the uncontrollable growth of Li dendrites during cycling process gives rise to problems as capacity decay and short circuit, suppressing the cycling and safety performances of Li metal battery. In this contribution, porous conductive interlayer (PCI), composed of carbon nanofibers (CNFs) and polyisophthaloyl metaphenylene diamine (PMIA), is developed to suppress Li dendrites and stabilize Li metal anode. PCI possesses the excellent conductive ability of CNFs and the preeminent mechanical properties of PMIA at the same time. When Li metal contacts with PCI during cycling process, an equipotential surface forms on their interface, which eliminates the tip effect on Li anode and homogenizes Li-ions flux in combination with the uniform porous structure of PCI. Employed PCI, the Li vertical bar Cu cell exhibits a remarkable cycling stability with a high average Coulombic efficiency of 97.5% for 100 cycles at 0.5 mA cm(-2). And the Li vertical bar LiFePO4 cell exhibits improved rate capability (114.7 mAh g(-1) at 5.0 C) and enhanced cycling performance (78.9% capacity retention rate over 500 cycles at 1.0 C). This work provides a fresh and effective solving strategy for the problem of dendrites in Li metal battery. (C) 2020 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

A porous conductive interlayer (PCI) composed of carbon nanofibers (CNFs) and polyisophthaloyl metaphenylene diamine (PMIA) was developed to suppress the growth of lithium dendrites, improving the performance of lithium metal batteries and providing a fresh strategy for solving dendrite-related issues.