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Kwiibhetri ze-lithium-ion, ukufezekisa injongo ye-350 Wh Kg-1, izinto ze-cathode zisebenzisa i-nickel-rich rich layered oxide (LiNixMnyCozO2, x +y + z = 1, ebizwa ngokuba yi-NMCxyz). Ngokunyuka koxinzelelo lwamandla, iingozi ezinxulumene nokubaleka kwe-LIBs kutsale umdla wabantu. Ukusuka kumbono wezinto eziphathekayo, i-electrode ene-nickel ecebileyo inemiba enzulu yokhuseleko. Ukongeza, i-oxidation / crosstalk yamanye amacandelo ebhetri, afana ne-organic liquids kunye ne-electrode engalunganga, inokubangela ukubaleka kwe-thermal, ethathwa njengeyona nto iphambili yeengxaki zokhuseleko. Ukubunjwa kokulawulwa kwe-in-situ ye-stable electrode-electrolyte interface sisicwangciso esiphambili kwisizukulwana esilandelayo sebhetri ye-lithium-based based-energy-density. Ngokukodwa, i-cathode-electrolyte interphase eqinile kunye ne-dense (CEI) ene-thermal stability ephezulu yamacandelo e-inorganic inokusombulula ingxaki yokhuseleko ngokuthintela ukukhululwa kwe-oksijini. Ukuza kuthi ga ngoku, kukho ukunqongophala kophando kwizixhobo ze-CEI ze-cathode-modified kunye nokhuseleko lwenqanaba lebhetri.
Kungekudala, u-Feng Xuning, u-Wang Li, kunye no-Ouyang Minggao weYunivesithi yaseTsinghua bapapashe iphepha lophando elinesihloko esithi "I-In-Built Ultraconformal Interphases Yenza i-High-Safety Practical Practical Lithium Battery" kwi-Energy Storage Materials. Umbhali uvavanye ukusebenza kokhuseleko lwe-NMC811/Gr egcwele ibhetri ethambileyo kunye nokuzinza kwe-thermal ye-electrode efanelekileyo ye-CEI ehambelanayo. Indlela yokucinezela i-thermal ebalekayo phakathi kwezinto kunye nebhetri yepakethi ethambileyo ifundwe ngokubanzi. Kusetyenziswa i-electrolyte eneperfluorinated engatshiyo, i-NMC811/Gr pouch-type-bettery-type yebhetri yalungiswa. Uzinzo olushushu lwe-NMC811 luphuculwe yi-in-situ eyenziwe ngumaleko okhuselayo we-CEI otyebileyo kwi-inorganic LiF. I-CEI ye-LiF inokunciphisa ngokufanelekileyo ukukhutshwa kwe-oksijini okubangelwa yinguqu yesigaba kwaye inqanda ukusabela kwe-exothermic phakathi kwe-NMC811 eyonwabileyo kunye ne-electrolyte ene-fluorinated.
Umzobo 1 Uthelekiso lweempawu zokubaleka ezishushu ze-NMC811/Gr isingxobo sohlobo lwebhetri egcweleyo kusetyenziswa i-electrolyte ene-perfluorinated kunye ne-electrolyte eqhelekileyo. Emva komjikelo omnye wemveli (a) EC/EMC kunye (b) ne-perfluorinated FEC/FEMC/HFE electrolyte pouch uhlobo lweebhetri ezipheleleyo. (c) I-electrolysis ye-EC/EMC eqhelekileyo kunye (d) ne-perfluorinated FEC/FEMC/HFE i-electrolyte pouch-type yebhetri egcweleyo ubudala emva kwemijikelo eyi-100.
Kwibhetri ye-NMC811/Gr ene-electrolyte yesintu emva komjikelo omnye (Umfanekiso 1a), i-T2 iku-202.5°C. I-T2 yenzeka xa i-voltage ye-open-circuit yehla. Nangona kunjalo, i-T2 yebhetri esebenzisa i-electrolyte ene-perfluorinated ifikelela kwi-220.2 ° C (Umfanekiso 1b), obonisa ukuba i-electrolyte ene-perfluorinated inokuphucula ukhuseleko lwe-thermal yebhetri ukuya kwinqanaba elithile ngenxa yokuzinza kwayo okuphezulu kwe-thermal. Njengoko ibhetri iguga, ixabiso le-T2 lebhetri yesiqhelo ye-electrolyte lehla ukuya kwi-195.2 °C (Figure 1c). Nangona kunjalo, inkqubo yokuguga ayichaphazeli i-T2 yebhetri usebenzisa i-electrolytes perfluorinated (Umfanekiso 1d). Ukongezelela, ixabiso eliphezulu le-dT / dt yebhetri usebenzisa i-electrolyte yendabuko ngexesha le-TR liphezulu njenge-113 ° C s-1, ngelixa ibhetri esebenzisa i-electrolyte perfluorinated yi-32 ° C s-1 kuphela. Umahluko kwi-T2 yeebhetri ezigugayo unokubalelwa kukuzinza kwe-thermal ye-NMC811 eyonwabileyo, ecuthwayo phantsi kwe-electrolyte eqhelekileyo, kodwa inokugcinwa ngokufanelekileyo phantsi kwe-electrolyte ene-perfluorinated.
Umzobo 2 Uzinzo lwe-Thermal lwe-delithiation ye-NMC811 ye-electrode efanelekileyo kunye nomxube webhetri we-NMC811/Gr. (A,b) Iimephu zeContour ze-C-NMC811 kunye ne-F-NMC811 synchrotron high-energy XRD kunye notshintsho oluhambelanayo (003) lwe-diffraction peak. (c) Ukufudumala kunye nokukhutshwa kwe-oxygen ukuziphatha kwe-electrode efanelekileyo ye-C-NMC811 kunye ne-F-NMC811. (d) Ijika le-DSC lomxube wesampulu ye-electrode eyonwabileyo, i-electrode ene-lithiated negative, kunye ne-electrolyte.
Amanani 2a kunye ne-b abonisa iigophe ze-HEXRD ze-NMC81 eyonwabileyo kunye neengqimba ze-CEI ezahlukeneyo kubukho be-electrolyte eqhelekileyo kwaye ngexesha lobushushu begumbi ukuya kwi-600 ° C. Iziphumo zibonisa ngokucacileyo ukuba phambi kwe-electrolyte, uluhlu oluqinileyo lwe-CEI lunceda ukuzinza kwe-thermal ye-lithium-deposited cathode. Njengoko kubonisiwe kuMfanekiso 2c, i-F-NMC811 enye ibonise incopho ecothayo ye-exothermic kwi-233.8 ° C, ngelixa i-C-NMC811 exothermic yavela kwi-227.3 ° C. Ukongeza, ukuqina kunye nesantya sokukhutshwa kwe-oksijini okubangelwa yinguqu yesigaba se-C-NMC811 inzima ngakumbi kune-F-NMC811, iqinisekisa ngakumbi ukuba i-CEI eyomeleleyo iphucula ukuzinza kwe-thermal ye-F-NMC811. Umzobo 2d wenza uvavanyo lwe-DSC kumxube we-NMC811 eyonwabileyo kunye nezinye izixhobo zebhetri ezihambelanayo. Kwi-electrolyte eqhelekileyo, iincopho ze-exothermic zeesampulu ezinemijikelezo ye-1 kunye ne-100 zibonisa ukuba ukuguga kwe-interface yendabuko kuya kunciphisa ukuzinza kwe-thermal. Ngokwahlukileyo, kwi-electrolyte ene-perfluorinated, imizobo emva komjikelezo we-1 kunye ne-100 ibonisa iincopho ze-exothermic ezibanzi kunye nezincinci, ngokuhambelana ne-TR trigger yeqondo lokushisa (T2). Iziphumo (umzobo 1) ziyahambelana, zibonisa ukuba i-CEI eyomeleleyo inokuphucula ngokufanelekileyo uzinzo lwe-thermal lwabantu abadala kunye nolonwabo lwe-NMC811 kunye namanye amacandelo ebhetri.
Umfanekiso wesi-3 Ukubonakaliswa kwe-electrode eyonwabileyo ye-NMC811 kwi-electrolyte ene-perfluorinated. (ab) Imifanekiso ye-SEM enqamlezileyo ye-F-NMC811 endala ye-electrode efanelekileyo kunye nemephu ye-EDS ehambelanayo. (ch) Ukuhanjiswa kwezinto. (ij) Umfanekiso we-SEM onqamlezileyo we-F-NMC811 endala ye-electrode kwi-xy ebonakalayo. (km) Ukwakhiwa ngokutsha kwe-3D FIB-SEM ulwakhiwo kunye nokuhanjiswa kwendawo kwezinto F.
Ukuqinisekisa ukubunjwa okulawulwayo kwe-CEI ene-fluorinated, i-morphology ye-cross-sectional kunye nokusabalalisa i-electrode ye-NMC811 endala efunyenwe kwi-bettery ye-soft-pack yangempela ibonakaliswe yi-FIB-SEM (Umfanekiso 3 ah). Kwi-electrolyte ene-perfluorinated, i-uniform fluorinated CEI layer yenziwa kumphezulu we-F-NMC811. Ngokuchasene noko, i-C-NMC811 kwi-electrolyte eqhelekileyo ayinayo i-F kwaye yenza umaleko we-CEI ongalinganiyo. Isiqulatho sesiqalelo se-F kwicandelo elinqamlezileyo le-F-NMC811 (Umfanekiso 3h) uphezulu kunolo lwe-C-NMC811, nto leyo ingqina ngakumbi ukuba ulwakhiwo lwe-in-situ lwe-isophase engaphiliyo efulumileyo ngundoqo ekugcineni uzinzo lwe-NMC811 eyonwabileyo. . Ngoncedo lwe-FIB-SEM kunye nemephu ye-EDS, njengoko kubonisiwe kuMfanekiso 3m, iqwalasele izinto ezininzi ze-F kwimodeli ye-3D kumphezulu we-F-NMC811.
Umfanekiso we-4a) Ubunzulu be-elementi yosasazo kumphezulu we-electrode ye-NMC811 yoqobo kunye neyonwabileyo. (ac) I-FIB-TOF-SIMS ichitha usasazo lwe-F, O, kunye ne-Li element kwi-electrode efanelekileyo ye-NMC811. (df) Ukwakheka komhlaba kunye nosasazo olunzulu lwe-F, O, kunye ne-Li element ze-NMC811.
I-FIB-TOF-SEM iphinde yaveza ubunzulu bosasazo lweziqalelo kumphezulu we-electrode elungileyo ye-NMC811 (Umfanekiso 4). Xa kuthelekiswa neesampuli zangaphambili kunye ne-C-NMC811, ukunyuka okuphawulekayo kwe-F signal kufunyenwe kwinqanaba eliphezulu le-F-NMC811 (Umfanekiso 4a). Ukongezelela, i-O ebuthakathaka kunye neempawu eziphezulu ze-Li kumphezulu zibonisa ukubunjwa kwe-F- kunye ne-Li-rich CEI layers (Umfanekiso 4b, c). Ezi ziphumo zonke ziqinisekisile ukuba i-F-NMC811 inomaleko we-LiF-rich CEI. Xa kuthelekiswa ne-CEI ye-C-NMC811, umaleko we-CEI we-F-NMC811 uqulethe izinto ezininzi ze-F kunye ne-Li. Ukongeza, njengoko kubonisiwe kwiFIGS. 4d-f, ngokwembono yobunzulu be-ion etching, ulwakhiwo lwe-NMC811 yoqobo yomelele ngakumbi kunolo lwe-NMC811 eyonwabileyo. Ubunzulu be-etch ye-F-NMC811 yobudala buncinci kune-C-NMC811, okuthetha ukuba i-F-NMC811 inozinzo olubalaseleyo lwesakhiwo.
Umfanekiso we-5 CEI ukwakheka kweekhemikhali kumphezulu we-electrode elungileyo ye-NMC811. (a) I-spectrum ye-XPS ye-NMC811 ye-electrode efanelekileyo ye-CEI. (bc) I-XPS C1s kunye ne-F1s spectra ye-NMC811 yoqobo kunye neyonwabileyo ye-electrode ye-CEI. (d) I-Cryo-transmission electron microscope: ukuhanjiswa kwezinto ze-F-NMC811. (e) Umfanekiso we-TEM onomkhenkce we-CEI owenziwe kwi-F-NMC81. (fg) Imifanekiso ye-STEM-HAADF kunye ne-STEM-ABF ye-C-NMC811. (hi) Imifanekiso ye-STEM-HAADF kunye ne-STEM-ABF ye-F-NMC811.
Basebenzisa i-XPS ukubonakalisa ukubunjwa kweekhemikhali ze-CEI kwi-NMC811 (Umfanekiso 5). Ngokungafaniyo ne-C-NMC811 yoqobo, i-CEI ye-F-NMC811 iqulethe i-F enkulu kunye ne-Li kodwa i-C encinci (Umfanekiso 5a). Ukuncitshiswa kweentlobo ze-C kubonisa ukuba i-LiF-rich CEI inokukhusela i-F-NMC811 ngokunciphisa ukuphendula okuzinzileyo kwecala nge-electrolytes (Umfanekiso 5b). Ukongeza, iimali ezincinci ze-CO kunye ne-C=O zibonisa ukuba i-solvolysis ye-F-NMC811 ilinganiselwe. Kwi-spectrum ye-F1s ye-XPS (Umfanekiso we-5c), i-F-NMC811 ibonise isignali ye-LiF enamandla, eqinisekisa ukuba i-CEI iqulethe isixa esikhulu se-LiF esivela kwi-solvents ene-fluorinated. Imephu yezinto ze-F, O, Ni, Co, kunye ne-Mn kwindawo yendawo kwiincinci ze-F-NMC811 zibonisa ukuba iinkcukacha zisasazwa ngokufanayo ngokubanzi (Umfanekiso 5d). Umfanekiso we-TEM wobushushu obuphantsi kwi-Figure 5e ubonisa ukuba i-CEI inokusebenza njengomaleko okhuselayo ukugubungela ngokufanayo i-electrode ye-NMC811 efanelekileyo. Ukuqinisekisa ngakumbi ukuvela kolwakhiwo lwe-interface, i-engile ephezulu setyhula ye-dark-field scanning transmission electron microscopy (HAADF-STEM kunye nesetyhula ekhanyayo-intsimi yokuskena uthumelo lwe-electron microscopy (ABF-STEM) imifuniselo yenziwa. -NMC811), Umphezulu we-electrode ejikelezayo ejikelezayo uye watshintsha kakhulu kwisigaba, kwaye inqanaba letyuwa yelitye eliphazamisekileyo liqokelelwe kumphezulu we-electrode elungileyo (Umfanekiso 5f). i-electrode positive igcina isakhiwo esinemaleko (Figure 811h), ebonisa ingozi Isigaba sicinezelwa ngokufanelekileyo Ukongeza, umaleko we-CEI ofanayo wabonwa kumphezulu we-F-NMC5 (Umfanekiso 811i-g). Umaleko we-CEI kumphezulu we-electrode entle ye-NMC5 kwi-electrolyte ene-perfluorinated.
Umfanekiso we-6a) I-TOF-SIMS i-spectrum yesigaba se-interphase kumphezulu we-electrode e-NMC811 efanelekileyo. (ac) Uhlalutyo olunzulu lwamaqhekeza e-ion yesibini kwi-electrode efanelekileyo ye-NMC811. (df) I-TOF-SIMS yekhemikhali ye-spectrum ye-ion fragment yesibini emva kwemizuzwana ye-180 yokutshiza kwi-original, i-C-NMC811 kunye ne-F-NMC811.
Amaqhekeza e-C2F athathwa njengezinto eziphilayo ze-CEI, kunye ne-LiF2- kunye ne-PO2-amaqhekeza ahlala athathwa njengeentlobo ze-inorganic. Iimpawu eziphuculwe kakhulu ze-LiF2- kunye ne-PO2- zifunyenwe kuvavanyo (Umfanekiso 6a, b), ebonisa ukuba umaleko we-CEI we-F-NMC811 uqulethe inani elikhulu leentlobo ze-inorganic. Ngokuchasene noko, i-C2F-signal ye-F-NMC811 ibuthathaka kunaleyo ye-C-NMC811 (Figure 6c), nto leyo ethetha ukuba umaleko we-CEI we-F-NMC811 uqulethe iintlobo ze-organic eziethe-ethe. Uphando olongezelelweyo lufunyenwe (Umfanekiso 6d-f) ukuba kukho iintlobo ezininzi ze-inorganic kwi-CEI ye-F-NMC811, ngelixa kukho iindidi ezimbalwa ze-inorganic kwi-C-NMC811. Zonke ezi ziphumo zibonisa ukwakheka komgangatho oqinileyo we-CEI we-inorganic-rich kwi-electrolyte ene-perfluorinated. Xa kuthelekiswa ne-NMC811/Gr ibhetri ye-soft-pack kusetyenziswa i-electrolyte yesintu, ukuphuculwa kokhuseleko lwebhetri ye-soft-pack usebenzisa i-electrolyte ene-perfluorinated kunokubalelwa: Okokuqala, ukubunjwa kwe-in-situ yomaleko we-CEI otyebileyo kwi-inorganic LiF kunenzuzo. Ukuzinza kwe-thermal yendalo ye-electrode eyonwabileyo ye-NMC811 kunciphisa ukukhutshwa kwe-oksijini ye-lattice ebangelwa yinguqu yesigaba; okwesibini, umaleko okhuselayo we-inorganic we-CEI uthintela ngakumbi i-delithiation esebenzayo kakhulu ye-NMC811 ukuba iqhagamshelane ne-electrolyte, inciphisa ukusabela kwecala exothermic; okwesithathu, I-electrolyte ene-perfluorinated inozinzo oluphezulu lwe-thermal kumaqondo aphezulu.
Lo msebenzi unike ingxelo ngophuhliso lwe-Gr/NMC811 yesingxobo sohlobo lwebhetri epheleleyo kusetyenziswa i-electrolyte ene-perfluorinated, ephucule ngokubonakalayo ukusebenza kwayo kokhuseleko. Uzinzo lwe-thermal lwangaphakathi. Uphononongo olunzulu lwe-TR inhibition mechanism kunye nokulungelelaniswa phakathi kwezinto kunye namanqanaba ebhetri. Inkqubo yokwaluphala ayichaphazeli ubushushu be-TR trigger (T2) yebhetri ye-electrolyte ene-perfluorinated ngexesha lesiphango sonke, esineenzuzo ezicacileyo ngaphezu kwebhetri yokuguga usebenzisa i-electrolyte yendabuko. Ukongezelela, i-peak exothermic ihambelana neziphumo ze-TR, ezibonisa ukuba i-CEI eyomeleleyo inceda ukuzinza kwe-thermal ye-lithium-free positive electrode kunye nezinye izinto zebhetri. Ezi ziphumo zibonisa ukuba i-in-situ yolawulo loyilo lwe-CEI oluzinzile lunokubaluleka okukhokelayo okubalulekileyo ekusebenziseni okusebenzayo kweebhetri ze-lithium ezikhuselekileyo zamandla aphezulu.
I-In-Built Ultraconformal Interphases Yenza iBattery yeLithium eSebenzayo yoKhuseleko oluPhezulu, iziXhobo zokuGcina amandla, ngo-2021.
phendula kwiiyure ezi-6, nayiphi na imibuzo yamkelekile!
