Dab tsi yog yam ntxwv ntawm Lithium{0}}Ion roj teeb?
Peev xwm thiab Electromotive Force ntawm lithium{0}}ion roj teeb khoom
Thaum lub sij hawm them nqi - tso tawm cov tshuaj tiv thaiv ntawm lithium- ion roj teeb, tsuas yog cov khoom siv ntawm qhov zoo thiab qhov tsis zoo electrodes tau txais lithium- ion intercalation / deintercalation cov tshuaj tiv thaiv, thaum cov electrolyte thiab lwm yam khoom siv tsis tau noj. Yog li ntawd, lub peev xwm ntawm cov khoom zoo thiab tsis zoo electrode reversibly intercalate / deintercalate lithium ions txiav txim siab qhib - Circuit Court voltage ntawm lub roj teeb, thiab tus nqi ntawm lithium ions intercalating / deintercalating txiav txim siab lub peev xwm ntawm cov khoom siv. Ntau lub ntiaj teb lithium-ion roj teeb manufacturers thiab lithium-ion roj teeb cov chaw muag khoom cia siab rau cov khoom siv no kom ua tiav cov khoom lag luam ruaj khov thiab ua haujlwm zoo ib yam.
Rau qhov tsis zoo electrode, cov tshuaj tiv thaiv tshwm sim raws li Equation (1.2). Ib mole ntawm carbon (12g), qhov siab tshaj plaws ntawm 1/6 mol ntawm lithium ions tuaj yeem sib xyaw. Yog li ntawd, lub theoretical tshwj xeeb muaj peev xwm ntawm carbon tsis zoo electrode khoom yog
1/6 (mol) × 96485 (Faraday tas li, C / mol) / 12 (g) =3400C / g=372(mA·h / g) (1.5)
Hauv kev siv txhua hnub, txiav txim siab lithium poob vim adsorption thiab tsim cov khoom siv electrolyte interphase (SEI) zaj duab xis, qhov tseeb ua tiav cov peev txheej ntawm cov ntaub ntawv carbon yog 300-345 mA·h / g. Ua lithium-Ion roj teeb pob cov chaw muag khoom ua tiav qib no los ntawm kev ua kom zoo tshaj plaws graphite formulation thiab cov txheej txheem txheej txheej.
Rau cov khoom siv electrode zoo, nws lub peev xwm nyob ntawm seb cov lithium ions tuaj yeem muab rho tawm / ntxig. Siv LiCoO₂ ua piv txwv, txog li 1 mol ntawm lithium ions ib mole ntawm LiCoO₂ tuaj yeem koom nrog cov tshuaj tiv thaiv. Yog li, qhov theoretical tshwj xeeb muaj peev xwm ntawm LiCoO₂ (tus txheeb ze molecular mass 97.86) yog
1(mol) × 96485(C/mol)/97.86(g)=985.95C/g=273.9(mA·h/g) (1.6)
Hauv kev xyaum, kom muaj kev ruaj ntseg siv lead ua ntawm LiCoO₂ cov khoom, feem ntau tsuas yog 30% -60% ntawm lithium ions koom nrog cov tshuaj tiv thaiv. Yog li, lub peev xwm tshwj xeeb ntawm LiCoO₂ cov khoom siv yog 137-164 mA·h / g. Loj lithium-ion roj teeb OEM cov tuam txhab tswj qhov tob ntawm kev them nqi thiab tso tawm los ntawm BMS siab heev kom ua kom lub neej voj voog ntev tshaj plaws thaum ua kom muaj kev nyab xeeb.
Rau lithium hlau phosphate, 1 mol ntawm lithium ions ib mole ntawm lithium hlau phosphate tuaj yeem koom nrog hauv cov tshuaj tiv thaiv. Yog li, qhov theoretical thiab qhov tseeb muaj peev xwm ntawm lithium hlau phosphate cov khoom (cov txheeb ze molecular loj 157.8) yog
1(mol) × 96485(C/mol)/157.8(g)=611.44C/g=169.8(mA·h/g) (1.7)
Hauv qhov xwm txheej, tus qauv redox peev xwm ntawm Li / Li⁺ yog qhov qis tshaj plaws, ncav cuag -3.04 V (vs. standard hydrogen electrode). Rau cov ntaub ntawv carbon tsis zoo electrode, lub peev xwm ntawm lithium-ion extraction thiab ntxig yog nyob ze ntawm Li / Li⁺ equilibrium peev xwm. Raws li electrochemical txoj kev xav, nyob rau hauv chav tsev kub, lub electrode muaj peev xwm E ntawm cov pa roj carbon tsis zoo electrode yog
E=E℃+ 0.02567 · ln[C(Li⁺)/C(Li,C₆)] (1.8)
qhov twg
E℃- tus qauv electrode peev xwm;
C(Li⁺) - concentration ntawm lithium ions hauv cov tshuaj electrolyte;
C(Li,C₆) - concentration ntawm lithium ions nyob rau hauv qhov tsis zoo electrode carbon.
Thaum cov lithium ion concentration nyob rau hauv cov tshuaj thiab nyob rau hauv qhov tsis zoo electrode carbon nyob ze, lub electrode muaj peev xwm ntawm cov electrode tsis zoo sib npaug rau tus qauv txo qhov peev xwm E degree. Feem ntau, cov lithium ion concentration hauv cov electrolyte yog tsau, yog li kev hloov pauv hauv lithium ion concentration hauv cov pa roj carbon tsis zoo yuav ua rau muaj kev hloov pauv hauv qhov tsis zoo electrode. Tam sim no tsis muaj universal txoj kev los xam qhov tseeb equilibrium peev xwm ntawm Li/C₆ nrog sib txawv x qhov tseem ceeb. Nws yog feem ntau txiav txim siab sim. Kev sim qhia tau hais tias lub peev xwm delithiation ntawm graphite-raws li cov ntaub ntawv feem ntau txawv ntawm 0–0.4 V (vs. Li/Li⁺), ua rau lawv kuj tsim nyog cov ntaub ntawv tsis zoo electrode rau kev siv. Daim duab 1.2 qhia txog cov nqi them ib txwm- tso tawm cov yam ntxwv nkhaus ntawm graphite tsis zoo electrode.
Rau LiCoO₂ cov khoom siv hluav taws xob zoo, cov txheej txheem lithium intercalation / deintercalation yog ib zaug - cov tshuaj tiv thaiv theem. Raws li cov lithium ion concentration nyob rau hauv cov khoom zoo electrode hloov, lub peev xwm ntawm qhov zoo electrode kuj hloov. Xav txog cov lithium ion concentration hauv cov electrolyte yog 1 mol / L, rau cov tshuaj tiv thaiv hauv Equation (1.1), qhov zoo electrode muaj peev xwm E yog
E=E℃+ 0.02567 · ln[C(Li⁺,CoO₂)/C(LiCoO₂)] (1.9)
qhov twg
E℃- tus qauv electrode peev xwm;
C(LiCoO₂) - concentration of LiCoO₂ nyob rau hauv cov khoom zoo electrode;
C(Li⁺,CoO₂) - concentration of Li⁺ thiab CoO₂ nyob rau hauv cov khoom zoo electrode;
Raws li lithium ions raug rho tawm, qhov zoo electrode muaj peev xwm qhia tau tias muaj kev poob qis.
Tus nqi - cov txheej txheem tso tawm ntawm lithium hlau phosphate cov khoom yog hloov los ntawm lithium hlau phosphate mus rau hlau phosphate tom qab delithiation.
Cov tshuaj tiv thaiv ntawm lithium hlau phosphate electrode yog
LiFePO₄ ↔ FePO₄ + Li⁺ + e⁻ (1.10)
Nws lithium- ion intercalation / deintercalation txheej txheem yog ob theem - cov tshuaj tiv thaiv. Yog li, kev hloov pauv hauv lithium ion concentration hauv cov khoom siv electrode zoo tsis cuam tshuam qhov kev hloov pauv ntawm qhov zoo electrode. Nws lub peev xwm equilibrium yog
E=E℃+ 0.02567 · ln[C(FePO₄)/C(LiFePO₄)] (1.11)
Lub concentration ntawm cov khoom ntshiab yog 1. Raws li nws cov thermodynamic tsis, theoretical equilibrium muaj peev xwm yog 3.4 V.
Tus nqi raug coj - paug tus yam ntxwv nkhaus ntawm lithium hlau phosphate khoom yog qhia nyob rau hauv daim duab 1.3.
Cov yam ntxwv ua tau zoo ntawm Lithium{0}}ion roj teeb
Piv nrog rau lwm cov roj teeb, lithium - ion roj teeb muaj cov yam ntxwv hauv qab no uas tau lees paub los ntawm lithium - ion roj teeb distributors thiab cov neeg siv khoom lag luam:
Siab zog ceev.Lub zog ceev ntawm lithium{0}}ion roj teeb nce mus txog 100 W·h / kg thiab 200 W·h / L lossis ntau dua. Tsis ntev los no ternary cathode lithium-ion roj teeb tau ua tiav lub zog tshwj xeeb ntawm 200 W·h / kg. Siv siab -nickel silicon-raws li cov ntaub ntawv anode thiab lithium- cov ntaub ntawv nplua nuj cathode, lub zog tshwj xeeb yuav tsum ncav cuag 400 W·h / kg thiab lub zog ntim ntim 900 W·h / L, deb tshaj li cov roj teeb ib txwm muaj. Yog li ntawd, lithium{13}} ion roj teeb tau dav siv hauv cov khoom siv hluav taws xob thiab tsheb hluav taws xob.
Siab qhib- Circuit Court voltage.Vim yog siv cov kuab tshuaj uas tsis yog -aqueous organic solvents, ib qho - cell voltage nce mus txog 3.6–3.8 V, uas yog 2–3 npaug ntawm cov nickel-hlau hydride lossis nickel-cadmium roj teeb. Kev siv cov khoom siv hluav taws xob cathode muaj txiaj ntsig zoo tuaj yeem ua kom qhov kev ua haujlwm ntawm ib lub xov tooj ntawm tes mus rau 4.5-5 V, uas yog ib qho ntawm cov laj thawj tseem ceeb rau lub zog loj ntawm lithium - ion roj teeb.
Muaj peev xwm siab - tus nqi them thiab tso tawm.Piv txwv li, tag nrho -khoom- xeev lithium- ion roj teeb uas siv cov polymer electrolytes tuaj yeem ua tiav cov pa tawm siab tshaj 10C nrog kev nyab xeeb zoo; lithium- ion roj teeb siv lithium hlau phosphate raws li cov cathode tuaj yeem ua tiav 100C tawm.
Tsawg tus kheej - paug tus nqi.Nyob rau hauv chav tsev kub, lub hli tus kheej - paug tus nqi ntawm lithium- ion roj teeb feem ntau yog tsawg dua 10%, qis dua nickel-hlau hydride roj teeb (15%) thiab ib nrab ntawm cov nickel-cadmium roj teeb. Tus kheej - paug tus nqi ntawm lithium hlau phosphate roj teeb feem ntau tsawg dua 3%.
Ib puag ncig tus phooj ywg,tsis muaj txhuas, cadmium, mercury, los yog lwm yam teeb meem, thiab tsis ua phem rau ib puag ncig.
Tsis muaj teebmeem nco.Cov nyhuv nco yog hais txog qhov tshwm sim uas lub roj teeb muaj peev xwm txo qis thaum rov ua dua ua ntej tso tawm tag nrho lossis siv ua ntej kom them tag nrho (kev nco tsis muaj peev xwm lwj). Lithium-Ion roj teeb tsis muaj kev nco.
Kev nyab xeeb zoo.Lithium-Ion roj teeb feem ntau siv cov ntaub ntawv carbon raws li qhov tsis zoo electrode, uas muaj cov khoom siv hluav taws xob ze li ntawm cov hlau lithium. Lithium ions tuaj yeem thim rov qab intercalate thiab deintercalate hauv cov pa roj carbon monoxide, txo qhov tshwm sim ntawm lithium hlau deposition thiab txhim kho roj teeb kev nyab xeeb. Nyob rau hauv xyoo tas los no, nplaim taws- cov tshuaj tiv thaiv kab mob, nplaim taws- cov khoom sib cais, PTC (zoo kub coefficient) cov khoom siv, tawg- pov thawj li qub, roj teeb tswj systems, thiab lwm yam thev naus laus zis tau ua kom muaj kev nyab xeeb siab heev ntawm lithium- roj teeb ion.
Lub neej voj voog ntev.Lub neej voj voog ntawm lithium{0}} ion roj teeb feem ntau yog ntau tshaj 500 lub voj voog. Lub neej voj voog ntawm lithium hlau phosphate roj teeb feem ntau yog 2000-3000 cycles. Thaum sib txuam nrog cov khoom siv anode nrog lub voj voog muaj peev xwm siab (xws li lithium titanate), ntau tshaj 10,000 lub voj voog tuaj yeem ua tiav. Qhov no ua rau cov roj teeb lithium hlau phosphate yog qhov kev xaiv zoo tshaj plaws rau lub zog cia roj teeb thiab loj -scale ESS tej yaam num.
