摘要
Abstract
In the context of carbon neutrality goals,large-scale,long-duration energy storage is crucial for developing modern power systems primarily based on renewable energy.Zinc-bromine flow batteries,known for their low cost and high energy density,hold great promise in energy storage.As a semi-deposited battery,the size of zinc deposition areal capacity considerably impacts both the energy storage duration of the battery and its economic viability.Herein,highly conductive bipolar plates were employed,and defect engineering was implemented on the surface of the negative electrode of the zinc-bromine flow battery.This optimization successfully enhanced the cell structure of the battery and negative electrode,resulting in the outstanding battery performance under high areal capacity conditions.Furthermore,through characterization and comparison using methods such as scanning electron microscopy,X-ray photoelectron spectroscopy,Raman spectroscopy,cyclic voltammetry,electrochemical impedance spectroscopy,and Galvanostatic charge-discharge testing,moderately oxidized graphite felt was identified as the optimal electrode material.When combined with the optimized cell structure,the moderately oxidized graphite felt achieved remarkable performance.At a current density of 20 mA/cm2 and an areal capacity of 120 mAh·cm-2,the battery demonstrated an impressive 94.26%Coulombic efficiency and 82.12%energy efficiency.Finally,this study elucidates the mechanism behind this optimization strategy.The optimized cell stack structure considerably improves the distribution of internal currents in the battery,especially under low areal capacity conditions.As the areal capacity increases,achieving flat and dense zinc deposition while preventing zinc dendrite formation necessitates the integration of zincophilic defect engineering on the negative electrode surface.By integrating the optimized cell stack structure with the negative electrode material,exceptional battery performance is realized under high areal capacity conditions.This study provides robust support for the future application of zinc-bromine flow batteries as long-duration energy storage devices.关键词
锌溴液流电池/高面容量/均匀电流分布/电堆结构/缺陷工程Key words
zinc-bromine flow batteries/high areal capacity/homogenous current distribution/battery structure/defect engineering分类
信息技术与安全科学
