Yuav Ntsuas Lithium{0}}ion roj teeb Electrode Slurry li cas?

Hauv lithium-ion roj teeb ntau lawm, kev npaj slurry yog thawj txheej txheem. Qhov tsim nyog ntawm slurry tom qab sib tov ncaj qha cuam tshuam rau cov txheej txheem tom ntej thiab cov roj teeb zaum kawg, thiab yog qhov tseem ceeb ntawm cov nqi roj teeb. Yog li, kev npaj slurry plays lub luag haujlwm tseem ceeb hauv lithium-ion roj teeb tsim. Kev tshawb fawb qhia tau hais tias qhov zoo tshaj plaws microscopic particle tis ntawm lithium - ion roj teeb electrode yog tus cwj pwm los ntawm cov khoom tawg yooj yim ntawm cov khoom siv tsis muaj agglomeration, thiab nyias - txheej dispersion ntawm cov khoom siv hluav taws xob ua ib lub network. Cov roj teeb lithium-ion roj teeb ua los ntawm cov electrodes nrog cov khoom siv sib xyaw ua kom pom cov khoom siv hluav taws xob zoo heev thiab kev ua neej ntev. Yog li ntawd, lub flowability, stability, thiab uniformity ntawm lithium{10}}ion roj teeb slurries feem ntau yog kuaj thiab tus yam ntxwv los soj ntsuam lawv tsim nyog rau txheej txheem txheej tom ntej thiab lawv pab rau kev ua tau zoo ntawm lub roj teeb cov khoom siv.

Hauv lithium-ion roj teeb ntau lawm, kev npaj slurry yog thawj txheej txheem. Qhov tsim nyog ntawm slurry tom qab sib tov ncaj qha cuam tshuam rau cov txheej txheem tom ntej thiab cov roj teeb zaum kawg, thiab yog qhov tseem ceeb ntawm cov nqi roj teeb. Yog li, kev npaj slurry plays lub luag haujlwm tseem ceeb hauv lithium-ion roj teeb tsim. Cov kev tshawb fawb tau pom tias qhov zoo tshaj plaws microparticle faib ntawm lithium - ion roj teeb electrodes yog tus cwj pwm los ntawm cov khoom tawg yooj yim ntawm cov khoom siv tsis muaj agglomeration, thiab nyias - txheej dispersion ntawm cov khoom siv hluav taws xob ua ib lub network. Cov roj teeb lithium-ion roj teeb ua los ntawm cov electrodes nrog cov khoom siv sib xyaw ua kom pom cov khoom siv hluav taws xob zoo heev thiab kev ua neej ntev. Yog li ntawd, qhov flowability, stability, thiab uniformity ntawm lithium{10}}ion roj teeb slurries feem ntau yog kuaj thiab tus yam ntxwv los soj ntsuam lawv tsim nyog rau txheej txheem txheej tom ntej thiab lawv cov hauj lwm zoo hauv kev txhim kho cov kev ua tau zoo ntawm cov khoom siv roj teeb.

Electrode slurries tsis yog -Newtonian kua, thiab muaj ob hom: zoo electrode slurries thiab tsis zoo electrode slurries, uas tau muab faib ua roj-raws li thiab dej-raws li systems. Lub stirred slurry yuav tsum muaj zoo flowability, stability, thiab uniformity. Cov xeev ntawm slurries nrog txawv flowability yog qhia nyob rau hauv daim duab. Tsis tshua muaj los yog siab viscosity, sedimentation, agglomeration, thiab tsis sib xws dispersion tuaj yeem cuam tshuam cov txheej txheem txheej tom ntej, ua rau muaj qhov tsis xws luag hauv macroscopic tsos ntawm electrode thiab inconsistencies hauv nws cov microstructure. Tsis zoo li cov kev cai rau slurry nyob rau hauv ib txwm papermaking thiab txheej industries, lub uniformity thiab stability ntawm lithium roj teeb slurry thaum kawg cuam tshuam rau lub roj teeb hluav taws xob kev ua tau zoo, ua rau muaj teeb meem xws li voltage degradation, txo lub voj voog lub neej, thiab cov roj teeb tsis zoo. Yog li ntawd, tsim nyog tus cwj pwm thiab kev ntsuam xyuas ntawm slurry ua ntej txheej los txiav txim nws haum rau kev ua yog ib qho tseem ceeb heev.

Thaum cov kua ntws tawm, kev sib txhuam sab hauv tshwm sim ntawm cov molecules; Cov cuab yeej no hu ua viscosity, ntsuas tus lej.

Viscosity=Shear Stress / Shear Rate

Cov kev sib raug zoo ntawm cov nqi shear thiab shear stress yog hu ua rheological nkhaus, feem ntau siv los piav txog qhov txawv ntawm slurry (kua) viscosity nrog shear yam ntxwv. Rheological curves tuaj yeem siv los paub qhov txawv ntawm cov kua dej. Rau Newtonian kua, kev sib raug zoo ntawm shear stress thiab shear npaum li cas ntawm lub rheological nkhaus yog ib txoj kab ncaj nraim los ntawm lub hauv paus chiv keeb.

Hauv kev tsim khoom,digital viscometer rotationalthiab rheometers feem ntau yog siv los ntsuas viscosity thiab rheological nkhaus. Viscometers yog qhov yooj yim rau kev khiav lag luam, thaum rheometers tuaj yeem ntsuas qhov dav thiab dav dua viscosity-shear rate / stress curves, thiab muab cov txiaj ntsig raug dua. Roj teeb slurries, raws li tsis yog -Newtonian kua, muaj ntau yam rheological zog, xws li shear thinning, viscoelasticity, thiab thixotropy.

Feem ntau lithium{0}}ion electrode slurries muaj cov yam ntxwv ntawm shear thinning. Raws li pom nyob rau hauv daim duab, shear viscosity txo nrog nce shear npaum li cas. Cov yam ntxwv no tau tshaj tawm hauv slurries nrog cov ntsiab lus siab. Nyob rau ntawm tus nqi siab dua, lub zog shear muaj zog cuam tshuam lub network qauv tsim ntawm cov ntaub ntawv, ua rau cov khoom ua kom rov ua kom zoo dua rau hauv cov qauv kev txiav txim siab dua qub rau ntawm qhov chaw shear, ua rau txo qis hauv viscosity thiab ncav cuag Newtonian toj siab ntawm tus nqi siab dua.

Qhov no tsis yog -Newtonian tus yam ntxwv yog qhov zoo nyob rau hauv txheej txheej txheej ntawm electrode npaj. Ua ntej siv lubelectrode txheej tshuab, cov slurry yog thauj los ntawm lub tank hloov mus rau txheej chamber los ntawm lub twj tso kua mis ntsia hlau. Thaum lub sij hawm tus txheej txheem no, lub slurry yog raug rau tsawg shear quab yuam thiab tseem nyob rau hauv lub siab viscosity lub xeev kom nws stability. Thaum lub slurry yog instantaneously ejected los ntawm lub txheej lub taub hau di ncauj, nws yog raug rau ib tug siab shear npaum li cas, nyob rau hauv uas taw tes lub slurry viscosity txo, xyuas kom meej txaus. Tom qab cov slurry raug xa mus rau cov khoom siv tam sim no, tus nqi qis qis, thiab nws tseem nyob hauv lub xeev siab viscosity. Qhov no tuaj yeem tiv thaiv los yog txo cov particle sedimentation thaum lub slurry nyob ruaj ruaj los yog thaum lub sij hawm ziab, ua kom cov txheej txheej tuab zoo ib yam.

Viscoelasticity kuj tseem yog cov qauv siv tseem ceeb rau kev ntsuas cov khoom slurry. Nws qhia txog kev sib raug zoo ntawm viscosity (kua) thiab elasticity (khoom) ntawm slurry; yooj yim muab, nws characterizes seb lub slurry yog zoo li cov kua los yog ib tug khoom. Yog tias lub roj teeb lithium slurry tsuas yog khov thiab tsis muaj elasticity, txoj hlua hnyav yuav tshwm sim thaum txheej txheej, ua rau cov txheej txheem tsis zoo. Yog li ntawd, lub lithium roj teeb slurry yuav tsum muaj ib tug tej yam kev kawm ntawm elasticity ntxiv rau viscosity, cia cov tawg filaments kom sai li sai tau thaum lub sij hawm txheej txheej thiab xyuas kom meej uniform txheej. Yog hais tias cov slurry muaj elasticity siab heev los yog tsis muaj viscosity nyob rau hauv tag nrho, nws qhia tau hais tias hnyav agglomeration los yog ib tug khoom -zoo li cov qauv, ua rau txheej tsis yooj yim sua.

Viscoelasticity feem ntau yog ntsuas los ntawm rheometer. Me me -amplitude vibrational shear force, xws li amplitude scanning thiab zaus scanning, yog siv los ntsuas viscoelasticity ntawm slurry.

Tus nqi shear yog txuas ntxiv los ntawm xoom mus rau tus nqi tas li, thiab qhov sib thooj shear stress tau kaw thaum lub sijhawm ua haujlwm no. Tom qab ntawd, tus nqi shear yuav maj mam txo mus rau xoom, thiab tus nqi sib thooj shear stress raug kaw. Lub kaw nkhaus ntawm shear tus nqi piv rau kev ntxhov siab shear tuaj yeem npaj tau; qhov nkhaus no hu ua thixotropic ib txwm nplhaib. Qhov loj dua qhov chaw ntawm lub nplhaib ib txwm, qhov ntau dua qhov kev ua tau zoo ntawm thixotropic, thiab vice versa.

Viscosity yog qhov tseem ceeb hauv kev ntsuas qhov ruaj khov ntawm lithium{0}}ion roj teeb slurries. Ob qho tib si siab thiab qis viscosities yog kev puas tsuaj rau txheej. High-viscosity slurries tsis tshua muaj kev daws teeb meem thiab muaj kev cuam tshuam zoo dua, tab sis cov viscosity ntau dhau ua rau cov qib tsis zoo, ua rau txheej txheej nyuaj thiab txo cov txheej txheem ceev. Tsim nyog txo viscosity pab txhim kho txheej txheej. Tsawg viscosity muab cov slurry flowability zoo thiab pab tshem tawm cov npuas npuas, tab sis tsis tshua muaj viscosity ua rau kom qhuav nyuaj, txo txheej ceev, exacerbates txheej tsis sib xws, thiab tej zaum yuav ua rau txheej txheej tawg thiab slurry agglomeration.

Thaum lub sij hawm tsim khoom, tshwj xeeb tshaj yog tom qab lub slurry tau sawv ntsug rau ib lub sij hawm, lub viscosity feem ntau hloov, feem ntau nyob rau hauv peb txoj kev: nce viscosity, txo viscosity, thiab tshwj xeeb mob.

(1) Ntxiv viscosity:Tom qab lub sijhawm ntev, cov colloid hloov ntawm lub xeev sol mus rau lub xeev gel, ua rau cov slurry viscosity nce. Maj mam stirring lub slurry yuav restore lub viscosity.

(2) viscosity txo:Viscosity txo qis thaum lub binder absorbs noo noo thiab dhau qhov kev hloov pauv, kev hloov pauv ntawm cov txheej txheem thaum nplawm, lossis degradation. Nthuav nplawm ntev, nrawm nrawm nrawm, thiab qhov tsis sib xws ntawm cov slurry thaum lub sij hawm homogenization tuaj yeem ua rau viscosity txo. Ntxiv slurry stabilizers, dispersants, los yog surfactants tuaj yeem txhim kho slurry stability los ntawm cov qauv ntawm kev them nqi rov qab thiab steric hindrance. Tsis tas li ntawd, tag nrho cov khoom yuav tsum tau qhuav kom huv si ua ntej homogenization.

(3) Cov xwm txheej tshwj xeeb:Cov ntaub ntawv nquag tuaj yeem nqus cov dej noo thaum lub sijhawm khaws cia lossis raug nplawm hauv qhov chaw siab -cov av noo, ua rau PVDF nqus cov dej noo thiab tsim cov "jelly-zoo li" slurry. Thaum cov slurry nthuav tawm ib qho tshwj xeeb tshaj tawm jelly-zoo li sib xws, nws siv tsis tau. Hauv qhov no, cov teeb meem slurry tuaj yeem qhuav, cov ntawv khi thiab NCM vaporized thiab sib cais, ces sieved, hauv av, thiab proportionally tov rau hauv ib txwm slurry. Nws tuaj yeem siv tau yam tsis muaj kev cuam tshuam cov roj teeb ua haujlwm. Yog li, txoj kev tiv thaiv zoo tshaj plaws yog kom qhuav cov khoom ua ntej homogenization, ntsuas cov dej noo, thiab nruj me ntsis tswj cov av noo thaum homogenization.

Qhov feem pua ​​​​ntawm cov khoom siv xws li cov khoom siv, cov khoom siv hluav taws xob, thiab cov binders hauv tag nrho cov khoom ntawm slurry yog hu ua cov ntsiab lus ntawm cov slurry. Feem ntau, cov ntsiab lus khoom yog nyob rau hauv thaj tsam ntawm 40% mus rau 70%. Txoj kev tseem ceeb rau kev soj ntsuam cov ntsiab lus yog cov txheej txheem kom qhuav. Ntsuas lub slurry nrog ib qhov loj ntawm M, muab tso rau ntawm ib tug tej yam kub kom qhuav cov kuab tshuaj, thiab ces hnyav nws dua nrog ib tug loj ntawm m. Cov ntsiab lus ntawm cov khoom yuav raug xam raws li m=M / M. Lub ntsuas dej noo tuaj yeem siv los ntsuas qhov ntsuas cov ntsiab lus ntawm cov slurry sai thiab meej. Lub ntsuas dej noo siv lub hauv paus ntsiab lus ntawm thermal poob phaus; nws uniformly heats tus qauv nrog lub teeb halogen kom evaporate cov kuab tshuaj, thiab xam cov khoom cov ntsiab lus los ntawm kev hloov ntawm huab hwm coj ua ntej thiab tom qab cua sov.

Nyob rau hauv tib homogenization txheej txheem thiab formulation, qhov siab dua cov khoom ntawm slurry, nws cov viscosity ntau dua. Ib yam li ntawd, qhov qis dua cov ntsiab lus, qhov qis dua qhov viscosity. Nyob rau hauv ib qho kev txiav txim siab rau cov ntsiab lus khoom, tus nqi siab dua qhia tias muaj kev ruaj ntseg dua slurry. Ua kom cov ntsiab lus muaj zog tuaj yeem txo cov kev siv hnyav, ua kom luv slurry sib tov lub sij hawm, thiab txhim kho txheej txheej thiab ziab kom qhuav. Txawm li cas los xij, raws li cov ntsiab lus ntawm cov khoom nce ntxiv, cov viscosity nce, qhov fluidity txo qis, ua rau cov txheej txheem nyuaj thiab ua rau hnyav dua ntawm cov khoom siv.

Hu rau tam sim no