Vim li cas lub peev xwm ntawm Lithium roj teeb qis dua thaum lub caij ntuj no?

Cov roj teeb lithium-ion tau siv dav rau lawv lub neej ntev, muaj peev xwm loj, thiab tsis muaj kev nco zoo txij li thaum lawv nkag mus rau hauv khw. Kev siv cov roj teeb lithium-ion kub tsawg muaj teeb meem xws li tsis muaj peev xwm, kev ua haujlwm hnyav, kev ua haujlwm tsis zoo, kev ua kom pom tseeb ntawm lithium nag lossis daus, thiab tsis sib npaug lithium deintercalation. Txawm li cas los xij, nrog kev nthuav dav ntawm daim ntawv thov kev lag luam, cov kev txwv coj los ntawm kev ua haujlwm tsis zoo ntawm cov roj teeb lithium-ion tau dhau los ua pom tseeb dua.

Raws li cov lus ceeb toom, lub peev xwm tso tawm ntawm lithium-ion roj teeb ntawm -20 degree tsuas yog kwv yees li 31.5 feem pua ​​​​ntawm qhov kub ntawm chav tsev. Kev ua haujlwm kub ntawm cov roj teeb lithium-ion ib txwm nyob nruab nrab ntawm -20 thiab ntxiv rau 55 degree . Txawm li cas los xij, hauv aerospace, tub rog kev lag luam, tsheb hluav taws xob thiab lwm qhov chaw, cov roj teeb yuav tsum ua haujlwm ib txwm nyob ntawm -40 degree . Yog li ntawd, nws yog ib qho tseem ceeb heev los txhim kho cov khoom uas tsis tshua muaj kub ntawm lithium-ion roj teeb.

Cov xwm txheej txwv qhov ntsuas kub qis ntawm Lithium-ion roj teeb

Nyob rau hauv qhov kub thiab txias ib puag ncig, lub viscosity ntawm cov electrolyte nce, thiab txawm ib feem solidifies, uas ua rau ib tug txo nyob rau hauv lub conductivity ntawm lithium-ion roj teeb.

Nyob rau hauv ib cheeb tsam uas tsis muaj kub, qhov compatibility ntawm cov electrolyte, qhov tsis zoo electrode thiab cov separator yuav tsis zoo.

Lithium yog hnyav heev los ntawm qhov tsis zoo electrode ntawm lithium-ion roj teeb nyob rau hauv qhov kub thiab txias ib puag ncig, thiab precipitated hlau lithium reacts nrog cov electrolyte, thiab nws cov khoom deposition ua rau ib tug nce nyob rau hauv thickness ntawm cov khoom electrolyte interface (SEI) .

Nyob rau hauv ib puag ncig uas tsis tshua muaj kub, lub diffusion system ntawm lithium-ion roj teeb nyob rau hauv cov khoom nquag txo, thiab tus nqi hloov pauv tsis kam (Rct) nce ntau.

Kev sib tham txog qhov Determinant Factors cuam tshuam rau qhov ntsuas kub qis ntawm Li-ion roj teeb

Cov kws tshaj lij lub tswv yim 1: Cov electrolyte muaj qhov cuam tshuam loj tshaj plaws ntawm qhov kub thiab txias ntawm cov roj teeb lithium-ion, thiab cov khoom muaj pes tsawg leeg thiab lub cev thiab tshuaj lom neeg ntawm cov electrolyte muaj qhov cuam tshuam tseem ceeb rau kev ua haujlwm kub ntawm lub roj teeb. Qhov teeb meem tshwm sim los ntawm lub voj voog roj teeb ntawm qhov kub qis yog: qhov viscosity ntawm electrolyte yuav nce, ion conduction tshaj tawm yuav qeeb, thiab electron migration tshaj tawm ntawm sab nraud Circuit Court yuav tsis sib xws. Yog li ntawd, lub roj teeb yuav ua rau polarized hnyav heev thiab lub peev xwm thiab qhov tso tawm yuav txo qis. Tshwj xeeb tshaj yog thaum them nyiaj ntawm qhov kub thiab txias, lithium ions tuaj yeem yooj yim tsim lithium dendrites ntawm qhov chaw ntawm cov electrode tsis zoo, ua rau lub roj teeb tsis ua haujlwm.

Qhov ntsuas kub qis ntawm cov electrolyte yog ze ze rau qhov conductivity ntawm electrolyte nws tus kheej. Cov electrolyte nrog cov conductivity siab tuaj yeem xa cov ions sai dua thiab tuaj yeem ua kom muaj peev xwm ntau dua ntawm qhov kub thiab txias. Qhov ntau dissociated lithium ntsev nyob rau hauv cov electrolyte, ntau migration tooj thiab ntau dua cov conductivity. Qhov siab dua qhov conductivity, qhov ceev ntawm ion conduction tus nqi, qhov me dua polarization, thiab qhov ua tau zoo ntawm lub roj teeb ntawm qhov kub thiab txias. Yog li ntawd, kev siv hluav taws xob ntau dua yog qhov tsim nyog rau kev ua tiav qhov kev ua tau zoo ntawm qhov kub thiab txias ntawm lithium-ion roj teeb.

Lub conductivity ntawm cov electrolyte muaj feem xyuam rau cov muaj pes tsawg leeg ntawm cov electrolyte, thiab txo cov viscosity ntawm cov kuab tshuaj yog ib txoj hauv kev los ua kom cov conductivity ntawm electrolyte. Cov kuab tshuaj zoo ntawm cov kuab tshuaj ntawm qhov kub thiab txias yog qhov lav ntawm ion thauj, thiab cov khoom siv electrolyte zaj duab xis tsim los ntawm electrolyte ntawm qhov tsis zoo electrode ntawm qhov kub thiab txias kuj yog tus yuam sij rau kev ua ntawm lithium ions, thiab RSEI yog lub ntsiab impedance. ntawm lithium-ion roj teeb nyob rau hauv qhov kub thiab txias ib puag ncig.

Cov kws tshaj lij 2: Qhov tseem ceeb tshaj plaws uas txwv qhov ntsuas kub qis ntawm lithium-ion roj teeb yog qhov ua kom muaj zog Li ntxiv rau qhov kev tawm tsam ntawm qhov kub thiab txias, tsis yog SEI zaj duab xis.

Tsawg-kub yam ntxwv ntawm cov ntaub ntawv cathode rau lithium-ion roj teeb

Tsawg kub cov khoom ntawm cov txheej txheem cathode

Cov txheej txheem txheej, uas tsis tsuas yog muaj qhov sib piv tsis tau zoo ntawm ib-seem lithium ion diffusion channel, tab sis kuj muaj cov qauv kev ruaj ntseg ntawm peb-dimensional channel, yog cov khoom lag luam ntxov tshaj plaws lithium-ion roj teeb cathode. Nws cov khoom sawv cev yog LiCoO2, Li(Co1-}xNix)O2 thiab Li(Ni, Co, Mn)O2 thiab lwm yam.