Cov kws ua haujlwm hauv University of California San Diego tau tsim cov roj teeb lithium-ion uas ua tau zoo ntawm qhov txias txias thiab kub kub kub, thaum ntim ntau lub zog.Cov kws tshawb fawb tau ua tiav qhov kev ua tau zoo los ntawm kev tsim cov electrolyte uas tsis yog tsuas yog muaj ntau yam thiab muaj zog thoob plaws qhov kub thiab txias, tab sis kuj sib xws nrog lub zog siab anode thiab cathode.
Cov roj teeb kub-resilienttau piav qhia hauv ib daim ntawv luam tawm lub lim tiam ntawm Lub Xya Hli 4 hauv Kev Ua Haujlwm ntawm National Academy of Sciences (PNAS).
Cov roj teeb zoo li no tuaj yeem tso cai rau lub tsheb hluav taws xob hauv cov huab cua txias mus deb dua ntawm ib qho nqi;lawv tseem tuaj yeem txo qhov xav tau ntawm cov tshuab cua txias kom lub tsheb cov roj teeb ntim ntawm cov cua sov hauv cov huab cua kub, hais tias Zheng Chen, tus xibfwb ntawm nanoengineering ntawm UC San Diego Jacobs School of Engineering thiab tus kws sau ntawv qib siab ntawm txoj kev tshawb no.
"Koj xav tau kev ua haujlwm kub hauv cov cheeb tsam uas qhov ntsuas kub ib puag ncig tuaj yeem ncav cuag tus lej peb npaug thiab txoj kev tseem kub dua.Hauv cov tsheb hluav taws xob, cov roj teeb feem ntau yog nyob rau hauv pem teb, ze rau txoj kev kub no, "hais Chen, uas kuj yog tus kws qhia ntawv ntawm UC San Diego Sustainable Power and Energy Center."Tsis tas li ntawd, cov roj teeb sov tsuas yog los ntawm kev ua haujlwm tam sim no thaum lub sijhawm ua haujlwm.Yog tias cov roj teeb tsis tuaj yeem zam qhov kev sov no ntawm qhov kub siab, lawv qhov kev ua tau zoo yuav ua rau poob sai. "
Hauv kev sim, cov ntaub ntawv pov thawj-ntawm-lub tswv yim roj teeb khaws cia 87.5% thiab 115.9% ntawm lawv lub zog muaj peev xwm ntawm -40 thiab 50 C (-40 thiab 122 F), feem.Lawv kuj muaj cov txiaj ntsig ntawm Coulombic siab ntawm 98.2% thiab 98.7% ntawm qhov kub thiab txias, raws li, uas txhais tau hais tias cov roj teeb tuaj yeem raug them ntau dua thiab tawm mus ua ntej lawv tsis ua haujlwm.
Cov roj teeb uas Chen thiab cov npoj yaig tsim tau yog ob qho tib si txias thiab kub ua haujlwm ua tsaug rau lawv cov electrolyte.Nws yog ua los ntawm cov kua dej ntawm dibutyl ether tov nrog lithium ntsev.Ib qho tshwj xeeb ntawm dibutyl ether yog tias nws cov molecules khi tsis muaj zog rau lithium ions.Hauv lwm lo lus, cov electrolyte molecules tau yooj yim tso tawm ntawm lithium ions thaum lub roj teeb khiav.Qhov kev cuam tshuam tsis muaj zog molecular no, cov kws tshawb fawb tau tshawb pom hauv kev tshawb fawb yav dhau los, txhim kho cov roj teeb ua haujlwm ntawm qhov kub qis dua.Ntxiv rau, dibutyl ether tuaj yeem siv tau yooj yim vim tias nws nyob twj ywm kua ntawm qhov kub thiab txias (nws muaj qhov kub ntawm 141 C, lossis 286 F).
Stabilizing lithium-sulfur chemistry
Dab tsi tseem ceeb ntawm cov electrolyte no yog tias nws tau sib xws nrog lithium-sulfur roj teeb, uas yog hom roj teeb uas muaj roj teeb uas muaj anode ua los ntawm lithium hlau thiab cathode ua los ntawm leej faj.Cov roj teeb lithium-sulfur yog ib feem tseem ceeb ntawm cov thev naus laus zis thev naus laus zis thev naus laus zis vim tias lawv cog lus tias muaj zog ntau dua thiab cov nqi qis dua.Lawv tuaj yeem khaws cia txog li ob npaug ntawm lub zog ib kilogram dua li niaj hnub no cov roj teeb lithium-ion - qhov no tuaj yeem ua ob npaug ntawm cov tsheb fais fab yam tsis muaj qhov hnyav ntawm lub pob roj teeb.Tsis tas li ntawd, leej faj muaj ntau dua thiab tsis tshua muaj teeb meem rau qhov chaw tshaj li cov cobalt siv nyob rau hauv cov tshuaj lithium-ion roj teeb cathodes.
Tab sis muaj teeb meem nrog cov roj teeb lithium-sulfur.Ob lub cathode thiab anode yog super reactive.Sulfur cathodes yog reactive heev uas lawv yaj thaum lub sij hawm ua hauj lwm roj teeb.Qhov teeb meem no tshwm sim thaum kub kub.Thiab lithium hlau anodes yog nquag tsim koob zoo li cov qauv hu ua dendrites uas tuaj yeem tho qhov ntawm lub roj teeb, ua rau nws luv luv.Yog li ntawd, cov roj teeb lithium-sulfur tsuas kav ntev txog kaum lub voj voog.
Chen hais tias "Yog tias koj xav tau lub roj teeb uas muaj zog ceev, feem ntau koj yuav tsum tau siv cov tshuaj lom neeg nyuaj heev," said Chen."Lub zog siab txhais tau tias muaj kev cuam tshuam ntau dua, uas txhais tau tias tsis muaj kev ruaj ntseg, ntau dua degradation.Ua kom lub roj teeb muaj zog uas ruaj khov yog ib txoj haujlwm nyuaj rau nws tus kheej - sim ua qhov no los ntawm qhov kub thiab txias yog qhov nyuaj dua. "
Lub dibutyl ether electrolyte tsim los ntawm UC San Diego pab neeg tiv thaiv cov teeb meem no, txawm tias qhov kub thiab txias.Cov roj teeb uas lawv tau sim muaj lub neej nyob ntev dua li lub roj teeb lithium-sulfur."Peb cov electrolyte pab txhim kho ob sab cathode thiab anode sab thaum muab siab conductivity thiab interfacial stability," said Chen.
Pab neeg no kuj tsim cov sulfur cathode kom ruaj khov dua los ntawm grafting rau polymer.Qhov no tiv thaiv ntau sulfur los ntawm dissolving rau hauv electrolyte.
Cov kauj ruam tom ntej no suav nrog kev ntsuas lub roj teeb chemistry, ua kom nws ua haujlwm ntawm qhov kub thiab txias ntxiv thiab txuas ntxiv lub neej voj voog.
Daim ntawv: "Cov txheej txheem xaiv cov kuab tshuaj rau cov roj teeb lithium-sulfur kub-resilient."Co-sau suav nrog Guorui Cai, John Holoubek, Mingqian Li, Hongpeng Gao, Yijie Yin, Sicen Yu, Haodong Liu, Tod A. Pascal thiab Ping Liu, tag nrho ntawm UC San Diego.
Txoj haujlwm no tau txais kev txhawb nqa los ntawm Kev Tshawb Fawb Txog Kev Ua Haujlwm Thaum Ntxov los ntawm NASA's Space Technology Research Grants Program (ECF 80NSSC18K1512), National Science Foundation los ntawm UC San Diego Materials Research Science thiab Engineering Center (MRSEC, grant DMR-2011924), thiab Office of Tsheb yees ntawm US Department of Energy los ntawm Advanced Battery Materials Research Program (Battery500 Consortium, daim ntawv cog lus DE-EE0007764).Txoj haujlwm no tau ua ib feem ntawm San Diego Nanotechnology Infrastructure (SDNI) ntawm UC San Diego, tus tswv cuab ntawm National Nanotechnology Coordinated Infrastructure, uas tau txhawb nqa los ntawm National Science Foundation (grant ECCS-1542148).
Post lub sij hawm: Aug-10-2022