第28卷 第4期2023年8月 哈尔滨理工大学学报JOURNALOFHARBINUNIVERSITYOFSCIENCEANDTECHNOLOGY Vol.28No.4Aug.2023 固态电解质LiZr2(PO4)3的掺杂及其在电极中的应用刘少鹏, 王基任, 拓沅辛, 周春山, 周 爽, 张永泉(哈尔滨理工大学电气与电子工程学院工程电介质及其应用教育部重点实验室,哈尔滨150080)
摘 要:NASICON型固态电解质磷酸锆锂(LZP)具有优异的结构稳定性和性能可靠性,但其在室温下的锂离子电导率较低,限制锂离子的传输。针对上述问题,采用溶胶凝胶法对磷酸锆锂电解质材料进行阳离子掺杂,提高材料的电导率,进而提升锂离子在材料中的输运能力。同时,将掺杂的磷酸锆锂电解质对电极进行修饰,提升电极本身的锂离子输运性能。探究了离子掺杂电解质对电极的锂离子扩散动力学性能的影响机理。实验结果表明,LiTi0.25Zr1.75(PO4)3对电极的锂离子扩散动力学性能提高最为显著,锂离子扩散系数达到3.25×10-14cm2·S-1,是未修饰电极的2.95倍,同时在5C倍率下,LiTi0.25Zr1.75(PO4)3修饰的电极比未修饰电极比容量提高了25.48mAh·g-1。关键词:固态电解质;磷酸锆锂;掺杂;离子输运;电化学DOI:10.15938/j.jhust.2023.04.002中图分类号:TM911.3文献标志码:A文章编号:1007-2683(2023)04-0008-06DopingModificationofSolidElectrolyteLiZr2(PO4)3andItsApplicationinElectrodesLIUShaopeng, WANGJiren, TUOYuanxin, ZHOUChunshan, ZHOUShuang, ZHANGYongquan(KeyLaboratoryofEngineeringDielectricsandItsApplication,MinistryofEducation,SchoolofElectricandEngineering,HarbinUniversityofScienceandTechnology,Harbin150080,China)Abstract:NASICONtypesolidelectrolyteLiZr2(PO4)3hasexcellentstructuralstabilityandperformancereliability,butitslowconductivityoflithiumionsatroomtemperaturelimitsthetransportoflithiumions.Inviewoftheaboveproblems,cationicdopingofLiZr2(PO4)3electrolytematerialwasstudiedbysol-gelmethodandthusimprovethetransportcapacityoflithiumionsinthematerial.Meanwhile,modifiedtheelectrodewithdopedLiZr2(PO4)3electrolytetoimprovethelithiumiontransportperformanceoftheelectrodeitself.Theinfluencemechanismofion-dopedelectrolyteonlithiumiondiffusionkineticsofelectrodewasinvestigated.TheexperimentalresultsshowthatLiTi0.25Zr1.75(PO4)3improvesthelithiumiondiffusionkineticsmostsignificantly,andthelithiumiondiffusioncoefficientreaches3.25×10-14cm2·S-1,whichis2.95timesofthatoftheunmodifiedelectrode.At5Crate,thespecificcapacityofLiTi0.25Zr1.75(PO4)3modifiedelectrodeis25.48mAhg-1higherthanthatoftheunmodifiedelectrode.Keywords:solid-stateelectrolyte;LiZr2(PO4)3;doping;ionictransport;electrochemistry