摘要
隔膜是锂离子电池的重要组成部分之一,具有隔绝正负极片防止短路和提供锂离子传输通道的作用。提高电池安全性能和降低隔膜尘产成本是未来锂离子电池研究的主要目标之~,在本论文中,高安全性和低成本的生物质材料纤维素被用来制备锂离子电池隔膜。主要研究工作包括以下几方面:福白菊
(1)用PFI磨浆机和超细摩擦研磨机分别将麻浆粕、棉浆粕、木浆粕进行磨浆处理,观察不同磨浆条件下纤维素纤维的帚化与分纤情况,选取适宜的浆粕和探索最佳的打浆分纤技术。结果表明将麻浆粕经PFI磨浆机磨浆2力.转以后,再经过超细摩擦研磨机研磨的微纤化纤维,适合通过抄纸工艺大规模制造纤维素基复合隔膜。
(2)将天然纤维素纤维和芳砜纶纤维按照不同比例混合,构建微米、纳米多级结构的高性能锂离子电池复合隔膜,并测试其浸润性、热稳定性、机械性能和电化学性能。结果表明在纤维素和芳砜纶质量比为3:1的情况下,制备的纤维素/芳砜纶复合隔膜的综合性能最好,而且采用纤维素/芳砜纶复合隔膜组装的磷酸铁锂半电池在120℃下仍然表现出了优异的电化学性能。
2010安徽中考语文(3)为了解决纤维素隔膜强度低和孔径大的问题,采用生物质材料多巴胺对纤维素进行表面包覆。由于多巴胺在pH=8.5的缓冲溶液中可以在纤维素表面自组装成具有粘附性的聚多巴胺,聚多巴胺包覆层使纤维素隔膜具有致密的多孔结构和高的机械强度,有利于提高电池的安全性,并缓解电池的白放
外婆怀了外孙的种电。同时多巴胺包覆层使电极、电解液和隔膜之问的接触更加紧密,有利于提高电池的电化学性能。
过硫酸钠关键词:纤维素;多巴胺;复合隔膜;锂离子电池
Abstract
Asoneofthekeycomponentsinlithium·ionbauery,theseparatorplaysanimportantroleininsulatingthecathodeandanodetoavoidshortcircuitsandalsoprovidingmicroporestructureforrapidtransportoftheioncarriers.What’Smore.theexcellent
safetyperformanceandlow··costoflithium··ionbatteryseparatorisoneofthemaingoalsinthefutureresearch.Inthisdissertation,wedevotetoexploringtheapplicationofbiomasscelluloseinlithium—ionbakeryseparator.Themaincontentisdepictedasfollows:
(1)Hemppulp,cottonpulpandwoodpulpweregroundbyPFIpulpingmachineandultrafinegrindingmachine,respectively.Then,theoptimalpulpandbeatingtechnologyweredeterminedbyinvestigatingtheseparationanddefiberofdifferentcellulosepulp.Asaresult,hemppulpwasthebestmaterialtofabricmecellulosebasedcompositeseparatorbypapermakingprocessinlargescale.
(2)Cellulosepulpandpolysulfonamidepulpwithdifferentmassratiowereexploredtofabricatedcompositeseparatorbypapermakingprocess.Theperformanceofcompositeseparatorwasinvestigatedbywettability,heattolerance,mechanicalstrengthandelectrochemicalproperties.Itwasdemonstratedthatcellulosepulpandpolysulfonamide
溶血栓pulpwiththemassratioof3/1(w/w)obsessedthebes
逆向建模
tcomprehensiveperformance.What’Smore.thelithiumironphosphate/lithiumhalfcellusingcellulose/polysulfonamide
separatorstillexhibitedstablecharge.dischargecapabilityevenat120oC.(3)Celluloseseparatorstillhassomedisadvantagestobesolved,suchaslarge—sized
poresandtowmechanical
strength.Inordertotackletheseproblems,biomassdopamine
wasmotivatedtobindthesurfaceofcellulose.Dopaminecouldself-polymerizedtopolydopamineatpH8.5,furthermore,thepolydopaminecoatinglayerendowedcellulosewiththeabilityofadhesionwhichwasbeneficialtoenhancethemechanicalstrengtha
ndsafetyperformance.Meanwhile,thesuperiorinterfacialcompatibilityamongelectrode,
electrolyteandseparatorwasbeneficialto
improveelectrochemicalpropertiesof
batteries
KeyWords:Cellulose;Dopamine;Compositeseparator;Lithium—ionbattery