Dependence of lithium metal battery performances on inherent separator porous structure regulation  

作　　者：Lei Ding Dandan Li Lingyang Liu Pengfang Zhang Fanghui Du Chao Wang Daoxin Zhang Shuo Zhang Sihang Zhang Feng Yang 

机构地区：[1]Shandong Key Laboratory of Chemical Energy Storage and New Battery Technology,Institute of BioPharmceutical Research,School of Chemistry and Chemical Engineering,Liaocheng University,Liaocheng 252000,Shandong,China [2]State Key Laboratory of Polymer Materials Engineering,College of Polymer Science and Engineering,Sichuan University,Chengdu 610065,Sichuan,China [3]College of Materials Science and Engineering,Qingdao University of Science and Technology,Qingdao 266042,Shandong,China [4]School of Food Science and Engineering,Hainan University,Haikou 570228,Hainan,China

出　　处：《Journal of Energy Chemistry》2023年第9期436-447,共12页能源化学（英文版）

基　　金：the Natural Science Foundation of Shandong Province (ZR2022QB050);the Liaocheng University Doctoral Initial Fund (318052137) for Financial Support。

摘　　要：Boosting of rechargeable lithium metal batteries(LMBs) holds challenges because of lithium dendrites germination and high-reactive surface feature.Separators may experience structure-determined chemical deterioration and worsen Li plating-stripping behaviors when smoothly shifting from lithium-ion batteries(LIBs) to LMBs.This study precisely regulations the crystal structure of β-polypropylene and separator porous construction to investigate the intrinsic porous structure and mechanical properties determined electrochemical performances and cycling durability of LMBs.Crystal structure characterizations,porous structure analyses,and electrochemical cycling tests uncover appropriate annealing thermal stimulation concentrates β-lamellae thickness and enhances lamellae thermal stability by rearranging molecular chain in inferior β-lamellae,maximally homogenizing biaxial tensile deformation and resultant porous constructions.These even pores with high connectivity lower ion migration barriers,alleviate heterogeneous Li^(+) flux dispersion,stabilize reversible Li plating-stripping behaviors,and hinder coursing and branching of Li dendrites,endowing steady cell cycling durability,especially at higher currents due to the highlighted uncontrollable cumulation of dead Li,which offers new insights for the current pursuit of high-power density battery and fast charging technology.The suggested separator structure-chemical nature functions in ensuring cyclic cell stability and builds reliable relationships between separator structure design and practical LMBs applications.

关 键 词：Lithium metal battery Polyolefin separator Porous structure design Lithium dendrite regulation Cycling stability 

分 类 号：TM912[电气工程—电力电子与电力传动] TB383.2[一般工业技术—材料科学与工程]