Soo saarista iyo soo saarista baytariyada lithium ion waa nidaam si dhow ugu xidhan hal talaabo oo tignoolajiyadeed. Guud ahaan, wax soo saarka baytariga lithium waxaa ka mid ah habka wax soo saarka electrode, habka isu-ururinta batteriga iyo duritaanka dareeraha ugu dambeeya, precharge, samaynta iyo habka gabowga. Saddexdan marxaladood ee geeddi-socodka, nidaam kastaa waxaa loo qaybin karaa dhowr hannaan oo muhiim ah, tallaabo kasta waxay saameyn weyn ku yeelan doontaa waxqabadka ugu dambeeya ee batteriga.

In the process stage, it can be subdivided into five processes: paste preparation, paste coating, roller pressing, cutting and drying. In the battery assembly process, and according to the different battery specifications and models, roughly divided into winding, shell, welding and other processes. In the final stage of liquid injection, including liquid injection, exhaust, sealing, prefilling, formation, aging and other processes. The electrode manufacturing process is the core content of the whole lithium battery manufacturing, which is related to the electrochemical performance of the battery, and the quality of slurry is particularly important.

Mid ka mid ah, aragtida aasaasiga ah ee slurry

slurry batari Lithium ion waa nooc ka mid ah dareeraha, sida caadiga ah waxa loo qaybin karaa dareeraha Newtonian iyo dareere aan Newtonian ah. Waxaa ka mid ah, dareeraha aan Newtonian-ka ahayn waxa loo qaybin karaa dareere balaastiig ah, dareere aan Newtonian ahayn oo waqti ku tiirsan, dareere caag ah iyo dareere caag ah oo bingham ah. Dheecaanka Newtonian waa dareere viscosity hooseeya kaas oo si fudud u qallafsanaan kara walaaca hoostiisa iyo diiqada xiiridu waxay la mid tahay heerka qallooca. Dheecaan kaas oo cidhiidhiga xiiridu yahay meel kasta waa shaqo toosan oo ah heerka qallooca xiirid. Dheecaanno badan oo dabiici ah ayaa ah dareeraha Newtonian. Inta badan dareerayaasha saafiga ah sida biyaha iyo aalkolada, saliida fudud, xalalka isku xidhka molecular hooseeya iyo gaaska socodka hooseeya waa dareerayaasha Newtonian.

Dheecaan aan ahayn newtonian waxa loola jeedaa dareeraha aan ku qancin sharciga tijaabada ah ee Newton ee viscosity, taas oo ah, xidhiidhka ka dhexeeya cadaadiska xiirid iyo cadaadiska xiirid maaha mid toosan. Dheecaannada aan cusbayn ayaa si weyn looga helaa nolosha, wax soo saarka iyo dabeecadda. Polymers-yada isku-urursan xalalka iyo joojinta polymers-ka guud ahaan waa dareere aan Newtonian ahayn. Inta badan dareerayaasha noolaha ayaa hadda lagu qeexaa inay yihiin dareere aan Newtonian ahayn. Dheecaannada aan cusbayn waxaa ka mid ah dhiigga, lymfa, iyo dheecaannada cystic, iyo sidoo kale “dareereyaal badheed” sida cytoplasm.

Biyo-baxa korantada wuxuu ka kooban yahay noocyo kala duwan oo alaab cayriin ah oo leh cuf-jiid gaar ah oo kala duwan iyo cabbirka walxaha, waana la isku daray oo lagu kala firdhiyey marxaladda dareeraha adag. slurry la sameeyay waa dareere aan Newtonian ahayn. slurry batari lithium waxaa loo qaybin karaa laba nooc oo togan iyo slurry taban, sababtoo ah nidaamka slurry (saliid, biyaha) kala duwan, dabeecadiisu way kala duwanaan doontaa. Si kastaba ha ahaatee, xuduudaha soo socda ayaa loo isticmaali karaa si loo go’aamiyo sifooyinka slurry:

1. Viscosity of slurry

Viscosity waa cabbirka viscosity-ka dareeraha iyo muujinta xoogga dareeraha ee ifafaale khilaafaad gudaha ah. Marka dareeruhu socdo, waxay soo saartaa khilaaf gudaha ah oo u dhexeeya unugyadeeda, kaas oo loo yaqaan ‘viscosity of dareeraha’. Viscosity waxaa lagu muujiyaa viscosity, kaas oo loo isticmaalo in lagu garto qodobka iska caabinta ee la xidhiidha sifooyinka dareeraha. Viscosity wuxuu u qaybsan yahay viscosity firfircoon iyo viscosity shuruudaysan.

Viscosity is defined as A pair of parallel plates, area A, Dr Apart, filled with A liquid. Now apply a thrust F to the upper plate to produce a velocity change DU. Because the viscosity of the liquid transfers this force layer by layer, each layer of liquid also moves accordingly, forming a velocity gradient du/ Dr, called shear rate, represented by R ‘. F/A is called shear stress, expressed as τ. The relationship between shear rate and shear stress is as follows:

(F/A) = eta (du/Dr)

Dheecaanka Newtonian wuxuu waafaqsan yahay caanaha Newton, viscosity wuxuu la xiriiraa heerkulka kaliya, maaha heerka xiirid, τ waxay la mid tahay D.

Non-newtonian fluids do not conform to Newton’s formula τ/D=f(D). The viscosity at a given τ/D is ηa, which is called apparent viscosity. The viscosity of non-Newtonian liquids depends not only on temperature, but also on shear rate, time, and shear thinning or shear thickening.

2. Guryaha slurry

Slurry waa dareere aan Newtonian ahayn, kaas oo ah dareere adag oo isku dhafan. Si loo buuxiyo shuruudaha geeddi-socodka daahan dambe, slurry wuxuu u baahan yahay inuu yeesho saddexda astaamood ee soo socda:

① Dareeraha wanaagsan. Dheecaannada waxaa lagu arki karaa kicinta qulqulka iyo u oggolaanshaha inuu si dabiici ah u qulqulo. Joogteynta wanaagsan, joogtada ah ee off iyo off macnaheedu waa dareere wanaagsan. Dheecaanku wuxuu la xidhiidhaa nuxurka adag iyo viscosity of slurry,

(2) simaynta. Dheefta slurry-ku waxay saamaysaa fidsanaanta iyo sinnaanta dahaarka.

③ Rheology. Rheology waxaa loola jeedaa sifooyinka qallafsanaanta qulqulka qulqulka, iyo hantidoodu waxay saameeyaan tayada xaashida tirka.

3. Slurry dispersion foundation

Wax soo saarka batari lithium ion, koollada cathode by koollada, wakiilka conductive, ka kooban walxaha cathode; Koodhka taban wuxuu ka kooban yahay xabag, budada graphite iyo wixii la mid ah. Diyaarinta slurry togan iyo taban waxaa ka mid ah taxane ah hababka teknoolajiyada, sida isku dhafka, kala dirida iyo kala firdhiso dareeraha iyo dareeraha, dareeraha iyo walxaha adag, waxaana weheliya isbeddelada heerkulka, viscosity iyo deegaanka ee habkan. Habka isku dhafka iyo kala firdhiso ee dareeraha baytariyada lithium ion waxaa loo qaybin karaa habka isku darka makro iyo habka kala firdhisanaanta yar yar, kuwaas oo had iyo jeer la socdo habka oo dhan ee diyaarinta dareeraha lithium ion batari. Diyaarinta slurry guud ahaan waxay martaa marxaladaha soo socda:

① Dry powder mixing. Particles contact each other in the form of dots, dots, planes, and lines,

② Semi-dry mud kneading stage. At this stage, after the dry powder is mixed evenly, the binder liquid or solvent is added, and the raw material is wet and muddy. After the strong stirring of the mixer, the material is subjected to the shear and friction of mechanical force, and there will be internal friction between the particles. Under each force, the raw material particles tend to be highly dispersed. This stage has a very important effect on the size and viscosity of the finished slurry.

③ heerka milanka iyo kala firdhisanaanta. Ka dib marka la cajiiyo, dareeraha ayaa si tartiib ah loogu daray si loo hagaajiyo viscosity slurry iyo content adag. Marxaladan, kala firdhisanaan iyo gardarro ayaa wada nool, ugu dambeyntiina waxay gaaraan xasillooni. Marxaladan, kala firdhinta agabka waxaa inta badan saameeya xooga farsamada, iska caabinta is jiid jiidka ee u dhexeeya budada iyo dareeraha, xoog xiirid xawaare sare leh, iyo isdhexgalka saamaynta u dhexeeya slurry iyo gidaarka weelka.

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Falanqaynta halbeegyada saameeya guryaha slurry

Waa tilmaame muhiim ah si loo hubiyo joogteynta batteriga ee habka wax soo saarka batteriga in slurry ay tahay inay lahaato xasillooni wanaagsan. Dhamaadka isku-dhafka isku-dhafka ah, joogsiyada isku-dhafka ah, slurry waxay u muuqan doontaa dejinta, qulqulka iyo ifafaale kale, taasoo keentay qaybo waaweyn, taas oo saameyn weyn ku yeelan doonta daboolka xiga iyo hababka kale. Halbeegyada ugu muhiimsan ee xasilloonida slurry waa dareeraha, viscosity, content adag iyo cufnaanta.

1. Viscosity of slurry

The stable and appropriate viscosity of electrode paste is very important to the coating process of electrode sheet. The viscosity is too high or too low is not conducive to polar piece coating, the slurry with high viscosity is not easy to precipitate and the dispersion will be better, but the high viscosity is not conducive to leveling effect, is not conducive to coating; Viscosity too low is not good, viscosity is low, although the slurry flow is good, but it is difficult to dry, reduce the drying efficiency of coating, coating cracking, slurry particle agglomeration, surface density consistency is not good.

Dhibaatada inta badan ku dhacda habka wax-soo-saarkayaga waa isbeddelka viscosity, iyo “isbeddelka” halkan waxaa loo qaybin karaa isbeddel degdeg ah iyo isbeddel taagan. Isbeddelka ku meel gaadhka ahi waxa uu tilmaamayaa isbeddelka ba’an ee ku yimaadda habka tijaabada viscosity-ka, iyo isbeddelka taagani waxa loola jeedaa isbeddelka viscosityka muddo ka dib. Viscosityku wuu kala duwan yahay sare ilaa hoose, mid sare ilaa hoose. Guud ahaan, arrimaha ugu muhiimsan ee saameeya viscosity slurry waa xawaaraha isku dhafka slurry, xakamaynta wakhtiga, nidaamka maaddooyinka, heerkulka deegaanka iyo qoyaanka, iwm. Waxaa jira arrimo badan, marka aan la kulanno isbeddelka viscosity waa sida loo falanqeeyo oo loo xalliyo? Viscosity of slurry asal ahaan waxaa go’aamiya xiraha. Bal qiyaas in la’aanteed xidhaha PVDF/CMC/SBR (FIG. 2, 3), ama haddii xidhehu aanu si fiican isku darin arrinta nool, arrinta adag ee nool iyo wakiilka conductive ma samayn doonaan dareere non-Newtonian oo daahan lebbisan? Ha samayn! Sidaa darteed, si loo falanqeeyo oo loo xalliyo sababta isbeddelka viscosity slurry, waa inaan ka bilownaa dabeecadda binder iyo slurry dispersion degree.

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FIG 2. Qaab-dhismeedka molecular ee PVDF

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Figure 3. Molecular formula of CMC

(1) viscosity ayaa kordha

Nidaamyada slurry ee kala duwan waxay leeyihiin xeerar isbeddelka viscosity kala duwan. Waqtigan xaadirka ah, nidaamka slurry-ga caadiga ah waa nidaamka saliidda PVDF/NMP ee togan, iyo slurry taban waa graphite /CMC/SBR nidaamka aqueous.

① Viscosity of slurry togan ayaa kordhiya muddo ka dib. Mid ka mid ah sababaha (meelaynta wakhti gaaban) ayaa ah in xawaaraha isku dhafka ah ee qulqulaya uu aad u degdegay, xiraha aan si buuxda u milmin, iyo budada PVDF ayaa si buuxda u milmaysa wakhti ka dib, iyo viscosity-ka ayaa kordha. Guud ahaan, PVDF waxay u baahan tahay ugu yaraan 3 saacadood si ay si buuxda u milmaan, iyada oo aan loo eegayn sida dhakhsaha badan ee xawaaraha kicintu aanu bedeli karin qodobkan saamaynta leh, waxa loogu yeero “degdega ayaa qashinka sameeya”. Sababta labaad (muddo dheer) ayaa ah in habka joogsiga slurry, kolloidku uu ka beddelo gobolka sol una beddelo jel. Waqtigan xaadirka ah, haddii ay isku mid tahay xawaare gaabis ah, viscosity ayaa dib loo soo celin karaa. Sababta saddexaad ayaa ah in qaab-dhismeed gaar ah uu ka dhex abuurmay kolloid iyo walxo nool iyo qaybo wakiil ah. Xaaladdani waa mid aan dib loo celin karin, iyo viscosity slurry lama soo celin karo ka dib kordhinta.

Viscosity of slurry taban ayaa kordha. Viscosity of slurry taban waxaa inta badan sababa burburinta qaab-dhismeedka kelli ee binder, iyo viscosity of slurry ayaa kordhay ka dib markii oksaydheynta ee silsiladda kelli. Haddii maaddadu si xad dhaaf ah u kala firdhiso, cabbirka qaybta ayaa si weyn loo dhimi doonaa, iyo viscosity of slurry sidoo kale waa la kordhin doonaa.

(2) viscosity waa la dhimay

① The viscosity of positive slurry decreases. One of the reasons, adhesive colloid changes in character. There are many reasons for the change, such as strong shear force during slurry transfer, qualitative change of water absorption by binder, structural change and degradation of itself in the process of mixing. The second reason is that the uneven stirring and dispersion leads to the large area settlement of solid materials in the slurry. The third reason is that in the process of stirring, the adhesive is subjected to strong shear force and friction of equipment and living material, and changes in properties at high temperature, resulting in a decrease in viscosity.

Viscosity ee dheecaanka taban ayaa yaraada. Sababaha waxaa ka mid ah in ay jiraan wasakhyo isku qasan CMC. Inta badan wasakhda ku jirta CMC waa xabagta polymerka ah ee aan milmi karin. Marka CMC ay la jaanqaadi karto kaalshiyamka iyo magnesium, mawqifkeeda waa la dhimi doonaa. Sababta labaad waa sodium hydroxymethyl cellulose, taas oo inta badan ah isku dhafka C/O. Xoogga dammaanadda waa mid aad u daciif ah oo si fudud u burburiya xoogga xiirid. Marka xawaaraha kicinta uu aad u dheereeyo ama wakhtiga wax kicintu uu aad u dheer yahay, waxaa laga yaabaa in dhismaha CMC la burburiyo. CMC waxa ay door dhumuc iyo xasilin ka ciyaartaa qulqulka taban, waxa ayna door muhiim ah ka ciyaartaa kala firdhinta alaabta ceeriin. Marka qaab dhismeedkeeda la burburiyo, waxa hubaal ah in ay sababi doonto degenaansho qul-qulaya iyo hoos u dhigidda viscosity. Sababta seddexaad waa burburinta xirmooyinka SBR. Wax soo saarka dhabta ah, CMC iyo SBR ayaa inta badan loo doortaa inay wada shaqeeyaan, doorarkooduna waa kala duwan yahay. SBR waxay inta badan ka ciyaartaa doorka wax-ku-xidhaha, laakiin waxay u nugul tahay inay nadiifiso marka la walaaqo muddada-dheer, taasoo keenta dammaanadda dammaanadda iyo hoos u dhigista viscosity ee slurry.

(3) Duruufo gaar ah (Jelly-qaabeeya waqti sare iyo mid hoose)

In the process of preparing positive paste, the paste sometimes turns into jelly. There are two main reasons for this: first, water. Considering that the moisture absorption of living substances and the moisture control in the mixing process are not good, the moisture absorption of raw materials or the humidity of the mixing environment is high, resulting in the absorption of water by PVDF into jelly. Second, the pH value of slurry or material. The higher the pH value is, the control of moisture is more strict, especially the mixing of high nickel materials such as NCA and NCM811.

Viscosity of slurry is bedbeddela, mid ka mid ah sababaha laga yaabaa inay tahay in slurry aan si buuxda u xasilin habka baaritaanka, iyo viscosity ee slurry si weyn u saameeyaa heerkulka. Gaar ahaan ka dib marka lagu kala firdhiyo xawaaraha sare, waxaa jira heerkul gaar ah oo heerkulka gudaha ah ee slurry, iyo viscosity ee muunado kala duwan ma aha isku mid. Sababta labaad waa kala firidhsan liidata ee slurry, alaabta nool, binder, wakiilka conductive ma aha kala firidhsan wanaagsan, slurry ma aha dheecaan wanaagsan, viscosity slurry dabiiciga ah waa sare ama hooseeyo.

2. Cabbirka slurry

Ka dib marka slurry la isku daro, waxaa lagama maarmaan ah in la cabbiro xajmiga qaybta, iyo habka cabbirka cabbirka qaybuhu waa habka xoqidda. Cabbirka walxaha waa halbeeg muhiim ah oo lagu garto tayada qulqulka. Cabbirka qaybuhu wuxuu saameyn muhiim ah ku leeyahay habka daahan, habka duubista iyo waxqabadka batteriga. Aragti ahaan, inta yar ee cabbirka slurry waa, ka sii fiican. Marka xajmiga qaybtu aad u weyn tahay, xasiloonida slurry ayaa saameyn doonta, sedimentation, joogteynta slurry waa mid liidata. Inta lagu jiro habka daahan extrusion, waxaa jiri doona walxaha xannibaya, tiirarka qalalan ka dib godka, taasoo keentay dhibaatooyin tayada tiirka. Geedi socodka soo socda ee soo socda, ay sabab u tahay cadaadiska aan sinnayn ee aagga daahan xun, way fududahay in la sameeyo jebinta cirifka iyo dildilaaca maxalliga ah, taas oo keeni doonta dhibaato weyn in waxqabadka baaskiil, waxqabadka saamiga iyo waxqabadka ammaanka ee batteriga.

Walxaha firfircoon ee togan iyo kuwa taban, dhejisyada, wakiilada korantada iyo walxaha kale ee muhiimka ah waxay leeyihiin cabbir iyo cufnaanta qaybaha kala duwan. Inta lagu jiro habka walaaqaya, waxaa jiri doona isku-dhafka, extrusion, khilaaf, agglomeration iyo hababka kale ee xiriirka kala duwan. Marxaladaha alaabta ceeriin ee si tartiib tartiib ah isku qasan, qoyan by dareere, wax weyn oo jabay oo si tartiib tartiib ah u janjeera xasiloonida, waxaa jiri doona isku darka walxaha aan sinnayn, kala dirida xabagta liidata, agglomeration halis ah ee qaybaha ganaaxa, isbeddelada guryaha koollada iyo xaalado kale, taas oo noqon doonta u horseeda jiilka qaybo waaweyn.

Marka aan fahamno waxa sababa inay soo baxaan qaybo ka mid ah, waxaan u baahanahay inaan wax ka qabanno dhibaatooyinkan daawooyinka ku habboon. Sida isku dhafka budada qalalan ee alaabta, shakhsi ahaan waxaan u maleynayaa in xawaaraha isku-darka uu saameyn yar ku leeyahay heerka isku-dhafka budada qalalan, laakiin waxay u baahan yihiin wakhti ku filan si loo hubiyo isku-dhafka isku-dhafka budada qalalan. Hadda warshadeeyayaasha qaarkood waxay doortaan xabagta budada ah iyo qaar ka mid ah waxay doortaan xal dareere ah xabag wanaagsan, laba koollo oo kala duwan ayaa go’aaminaya habka kala duwan, isticmaalka xabagta budada ah waxay u baahan tahay waqti dheer si ay u milaan, haddii kale goor dambe waxay u muuqan doontaa barar, dib u soo kabashada, isbeddelka viscosity, iwm. agglomeration u dhexeeya qaybaha ganaax waa lama huraan, laakiin waa in aan hubinno in ay jirto khilaaf ku filan u dhexeeya alaabta si ay u awood qaybaha agglomeration si ay u muuqdaan extrusion, burburin, ku haboon in la isku daro. Tani waxay nooga baahan tahay inaan xakameyno nuxurka adag ee marxaladaha kala duwan ee slurry, maadada adag ee aad u hooseeya waxay saameyn doontaa kala firidhsanaanta u dhexeysa qaybaha.

3. Waxyaabaha adag ee slurry

Maaddada adag ee slurry waxay si dhow ula xiriirtaa xasilloonida slurry, habka isku midka ah iyo caanaha, heerka sare ee maadada adag ee slurry, way sii weyn tahay viscosity, iyo lidkeeda. Meel cayiman, marka uu kor u kaco viscosity, ayaa sare u kacaysa xasilloonida slurry. Marka aan naqshadeyno batteriga, waxaan guud ahaan ka soo saareynaa dhumucda xudunta udubdhexaadka ah ee awoodda batteriga ilaa naqshadeynta xaashida korantada, sidaas darteed naqshadeynta xaashida korantada waxay la xiriirtaa oo kaliya cufnaanta dusha sare, cufnaanta walxaha nool, dhumucda iyo xuduudo kale. Halbeegyada xaashida korantada waxaa lagu hagaajiyaa jaakad iyo rullaluley, iyo nuxurka adag ee slurry kuma laha saameyn toos ah. Haddaba, heerka nuxurka adag ee slurry ma wax yar baa?

(1) Solid content has a certain influence on improving the stirring efficiency and coating efficiency. The higher the solid content, the shorter the stirring time, the less solvent consumption, the higher the coating drying efficiency, saving time.

(2) Nuxurka adag wuxuu leeyahay shuruudo gaar ah oo loogu talagalay qalabka. Slurry oo leh maadooyin adag oo sarreeya ayaa leh khasaare sare oo qalab ah, sababtoo ah heerka sare ee maadada adag, ayaa ka sii daran xirashada qalabka.

(3) Qulqulka leh maaddo adag ayaa aad u deggan. Natiijooyinka baaritaanka xasiloonida ee qaar ka mid ah slurry (sida ku cad shaxanka hoose) waxay muujinayaan in TSI (indexability index) ee 1.05 ee kicinta caadiga ah ay ka sarreyso 0.75 ee habka walaaqaya ee viscosity-ga sare, sidaas darteed xasiloonida qulqulka ee la helay viscosity-sare habka walaaqaya ayaa ka fiican kan lagu helo habka walaaqinta caadiga ah. Laakiin slurry leh maado adag oo adag ayaa sidoo kale saameyn doona dareeraha, taas oo aad u adag qalabka iyo farsamayaqaannada habka daahan.

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(4) Qulqulka leh maadada adag ee sare waxay yarayn kartaa dhumucda u dhexeeya dahaarka waxayna yareyn kartaa caabbinta gudaha ee batteriga.

4. Cufnaanta saxarka

Cufnaanta cabbirku waa halbeeg muhiim ah oo ka tarjumaysa joogteynta cabbirka. Saamaynta kala firidhsan ee cabbirka waxaa lagu xaqiijin karaa iyadoo la tijaabinayo cufnaanta cabbirka meelo kala duwan. In tan laguma soo celin doono, iyada oo loo marayo soo koobida kor ku xusan, waxaan aaminsanahay in aan diyaarino koollada electrode wanaagsan.