Qhov cuam tshuam ntawm graphite porosity rau kev ua haujlwm ntawm electrode qhia tau ntau yam, suav nrog kev thauj mus los ntawm ion, lub zog ceev, kev coj tus cwj pwm polarization, kev ruaj khov ntawm lub voj voog, thiab cov khoom siv kho tshuab. Cov txheej txheem tseem ceeb tuaj yeem tshuaj xyuas los ntawm cov qauv kev xav hauv qab no:
I. Kev Ua Haujlwm Zoo ntawm Kev Thauj Ion: Porosity Txheeb Xyuas Kev Nkag Mus Rau Electrolyte thiab Txoj Kev Sib Kis Ion
Qhov Porosity Siab:
- Cov Zoo: Muab ntau txoj kev rau electrolyte nkag mus, ua kom cov ion diffusion sai dua hauv electrode, tshwj xeeb tshaj yog haum rau cov xwm txheej them sai. Piv txwv li, tus qauv electrode porous gradient (35% porosity ntawm txheej saum npoo thiab 15% ntawm txheej hauv qab) ua rau lithium-ion thauj mus los sai ntawm qhov chaw electrode, zam kev sib sau ua ke hauv zos thiab tiv thaiv kev tsim lithium dendrite.
- Kev Pheej Hmoo: Qhov porosity siab dhau (> 40%) yuav ua rau muaj kev faib tawm electrolyte tsis sib npaug, txoj kev thauj mus los ion ntev, polarization nce ntxiv, thiab txo qis kev them / tso tawm.
Qhov Porosity Tsawg:
- Cov Zoo: Txo cov kev pheej hmoo ntawm kev xau electrolyte, ua kom cov khoom siv electrode ntim ntau ntxiv, thiab txhim kho lub zog ceev. Piv txwv li, CATL tau nce lub zog ceev ntawm lub roj teeb los ntawm 8% los ntawm kev ua kom zoo dua qhov kev faib tawm ntawm cov khoom graphite kom txo qhov porosity los ntawm 15%.
- Kev Pheej Hmoo: Qhov porosity qis dhau (<10%) txwv tsis pub electrolyte wetting ntau, cuam tshuam kev thauj mus los ntawm ion, thiab ua kom lub peev xwm puas tsuaj sai dua, tshwj xeeb tshaj yog nyob rau hauv cov qauv electrode tuab vim yog qhov chaw polarization.
II. Lub Zog Ceev: Kev Sib Npaug ntawm Porosity nrog Kev Siv Cov Khoom Siv Nquag
Qhov Zoo Tshaj Plaws Porosity:
Muab qhov chaw cia khoom txaus thaum tswj hwm qhov ruaj khov ntawm cov qauv electrode. Piv txwv li, cov electrodes supercapacitor uas muaj porosity siab (> 60%) txhim kho lub peev xwm cia khoom los ntawm kev nce thaj chaw tshwj xeeb tab sis xav tau cov khoom siv hluav taws xob kom tiv thaiv kev siv cov khoom siv tsawg dua.
Qhov Porosity Heev:
- Ntau dhau: Ua rau muaj kev faib tawm ntawm cov khoom siv nquag, txo cov lithium ions koom nrog hauv cov tshuaj tiv thaiv ib chav tsev thiab txo qis zog ceev.
- Tsis Txaus: Ua rau cov electrodes ntom dhau, cuam tshuam rau lithium-ion intercalation / deintercalation thiab txwv tsis pub lub zog tso tawm. Piv txwv li, graphite bipolar phaj nrog porosity siab dhau (20–30%) ua rau roj xau hauv cov roj cell, thaum porosity qis dhau ua rau brittleness thiab manufacturing fractures.
III. Kev coj cwj pwm polarization: Porosity cuam tshuam rau kev faib tawm tam sim no thiab kev ruaj khov ntawm voltage
Porosity tsis sib xws:
Qhov sib txawv ntawm qhov sib txawv ntawm cov porosity ntawm lub electrode ua rau cov hluav taws xob hauv zos tsis sib npaug, ua rau muaj kev pheej hmoo ntawm kev them ntau dhau lossis kev tso tawm ntau dhau. Piv txwv li, cov electrodes graphite uas muaj cov porosity siab tsis sib xws qhia txog cov kab tso tawm tsis ruaj khov ntawm 2C tus nqi, thaum cov porosity sib xws tswj tau qhov xwm txheej ntawm kev them (SOC) thiab txhim kho kev siv cov khoom siv nquag.
Kev Tsim Qauv Porosity Gradient:
Kev sib xyaw ua ke ntawm cov txheej saum npoo uas muaj porosity siab (35%) rau kev thauj mus los sai nrog cov txheej hauv qab uas muaj porosity qis (15%) rau kev ruaj khov ntawm cov qauv ua rau txo qis qhov hluav taws xob polarization. Kev sim qhia tau tias cov electrodes peb txheej gradient porosity ua tiav 20% muaj peev xwm khaws cia ntau dua thiab 1.5 × lub neej voj voog ntev dua ntawm 4C tus nqi piv rau cov qauv sib xws.
IV. Kev Ruaj Ntseg ntawm Lub Voj Voog: Lub Luag Haujlwm ntawm Porosity hauv Kev Faib Tawm Kev Nyuaj Siab
Qhov Porosity Tsim Nyog:
Txo qhov kev ntxhov siab ntawm kev nthuav dav/kev sib txhuam thaum lub sijhawm them/tawm mus, txo qhov kev pheej hmoo ntawm kev puas tsuaj ntawm cov qauv. Piv txwv li, cov electrodes roj teeb lithium-ion nrog 15–25% porosity khaws cia >90% peev xwm tom qab 500 lub voj voog.
Qhov Porosity Heev:
- Ntau dhau: Ua rau lub zog ntawm lub electrode tsis muaj zog, ua rau tawg thaum lub sijhawm rov ua dua thiab lub peev xwm lwj sai.
- Tsis Txaus: Ua rau muaj kev ntxhov siab ntau ntxiv, tej zaum yuav tshem lub electrode ntawm lub collector tam sim no thiab cuam tshuam cov kev xa hluav taws xob.
V. Cov Khoom Siv Kho Tshuab: Qhov Cuam Tshuam ntawm Porosity rau Kev Ua Haujlwm Electrode thiab Kev Ruaj Khoov
Cov Txheej Txheem Tsim Khoom:
Cov electrodes uas muaj porosity siab xav tau cov txheej txheem calendering tshwj xeeb los tiv thaiv qhov pore collapse, thaum cov electrodes uas muaj porosity qis yuav ua rau muaj kev tawg thaum lub sijhawm ua haujlwm. Piv txwv li, cov phaj graphite bipolar nrog porosity >30% nyuaj rau ua tiav cov qauv ultra-thin (<1.5 hli).
Kev Ruaj Khov Ntev:
Qhov porosity muaj feem cuam tshuam zoo nrog cov nqi xeb ntawm electrode. Piv txwv li, hauv cov roj cell, txhua 10% nce hauv graphite bipolar plate porosity ua rau cov nqi xeb nce siab 30%, uas yuav tsum tau muaj cov txheej txheej saum npoo (piv txwv li, silicon carbide) kom txo qhov porosity thiab ntev lub neej.
VI. Cov Tswv Yim Txhim Kho: Qhov "Golden Ratio" ntawm Porosity
Cov Qauv Tsim Tshwj Xeeb Rau Daim Ntawv Thov:
- Cov Roj Teeb Uas Them Tau Sai: Cov porosity gradient nrog ib txheej saum npoo uas muaj porosity siab (30–40%) thiab txheej hauv qab uas muaj porosity qis (10–15%).
- Cov Roj Teeb Muaj Zog Siab: Porosity tswj tau ntawm 15–25%, ua ke nrog cov tes hauj lwm carbon nanotube conductive los txhim kho kev thauj mus los ntawm ion.
- Ib puag ncig hnyav heev (piv txwv li, cov roj cell kub siab): Porosity <10% kom txo qis cov pa roj xau, ua ke nrog cov qauv nanoporous (<2 nm) kom tswj tau permeability.
Cov Kev Kawm Txuj Ci:
- Kev Hloov Kho Khoom Siv: Txo qhov porosity ntawm cov khoom siv graphitization lossis ntxiv cov tshuaj uas tsim cov qhov pore (piv txwv li, NaCl) rau kev tswj qhov porosity.
- Kev Tsim Kho Tshiab: Siv 3D luam ntawv los tsim cov qhov sib txuas ntawm cov qhov (biomimetic pore networks) (piv txwv li, cov qauv ntawm cov nplooj ntawm cov leeg), ua tiav kev ua kom zoo dua ntawm kev thauj mus los ntawm cov ion thiab lub zog kho tshuab.
Lub sijhawm tshaj tawm: Lub Xya Hli-09-2025