ESM: Yakavakwa-mukati-yekupedzisira-conformal interface yeperfluorinated electrolyte kune anoshanda akakwira-energy lithium mabhatiri.

Kutsvagisa kumashure

Mumabhatiri e-lithium-ion, kuzadzisa chinangwa che350 Wh Kg-1, iyo cathode zvinhu inoshandisa nickel-rich layered oxide (LiNixMnyCozO2, x+y+z=1, inonzi NMCxyz). Nekuwedzera kwesimba resimba, njodzi dzine chekuita nekupisa kwekutiza kweLIBs dzakwezva vanhu kutarisa. Kubva pakuona kwezvinhu, nickel-rich positive maelectrode ane nyaya dzekuchengetedza dzakakomba. Pamusoro pezvo, oxidation/crosstalk yezvimwe zvinhu zvebhatiri, zvakaita sezvinwiwa zvemuchadenga uye maelectrode asina kunaka, zvinogonawo kukonzeresa kutiza kwekupisa, kunoonekwa sechikonzero chikuru chekuchengetedza matambudziko. Iyo in-situ inodzoreka kuumbwa kweyakagadzika electrode-electrolyte interface ndiyo yekutanga nzira yechizvarwa chinotevera chehigh-energy-density lithium-based mabhatiri. Kunyanya, yakasimba uye dense cathode-electrolyte interphase (CEI) ine yakakwirira thermal kugadzikana inorganic zvikamu zvinogona kugadzirisa dambudziko rekuchengetedza nekudzivisa kuburitswa kweokisijeni. Parizvino, pane kushomeka kwekutsvagisa paECI cathode-yakagadziridzwa zvinhu uye bhatiri-level chengetedzo.

Kubudirira kuratidza

Munguva pfupi yapfuura, Feng Xuning, Wang Li, naOuyang Minggao veTsinghua University vakaburitsa bepa rekutsvagisa rine musoro unoti "In-Built Ultraconformal Interphases Enable High-Safety Practical Lithium Batteries" paEneji Storage Materials. Munyori akaongorora kuita kwekuchengetedza kweiyo inoshanda NMC811/Gr yakapfava-yakazara bhatiri uye kugadzikana kwekupisa kweiyo inoenderana CEI yakanaka electrode. Iyo yekupisa inomhanya yekudzvinyirira meshini pakati pezvinhu uye yakapfava pack bhatiri yakadzidzwa zvizere. Kushandisa isingabatike perfluorinated electrolyte, NMC811/Gr homwe-mhando yebhatiri yakazara yakagadzirwa. Kugadzikana kwekupisa kweNMC811 kwakagadziridzwa ne-in-situ yakaumbwa CEI yekudzivirira layer yakapfuma inorganic LiF. Iyo CEI yeLiF inokwanisa kunyatso kudzikamisa kuburitswa kweokisijeni kunokonzerwa nekuchinja kwechikamu uye kumisa maitiro exothermic pakati peNMC811 inofadza uye fluorinated electrolyte.

Graphic guide

Mufananidzo 1 Kuenzanisa kwekupisa kwekupisa kwemaitiro anoshanda NMC811/Gr homwe-mhando yebhatiri yakazara uchishandisa perfluorinated electrolyte uye yakajairika electrolyte. Mushure mekutenderera kumwe kwechinyakare (a) EC/EMC uye (b) perfluorinated FEC/FEMC/HFE electrolyte pouch mhando mabhatiri akazara. (c) Zvakajairwa EC/EMC electrolysis uye (d) perfluorinated FEC/FEMC/HFE electrolyte pouch-mhando yakazara bhatiri ane makore pashure 100 kutenderera.

Kubhatiri reNMC811/Gr rine electrolyte yechinyakare mushure mekutenderera kumwechete (Mufananidzo 1a), T2 iri pa202.5°C. T2 inoitika kana iyo yakavhurika-yedunhu voltage inodonha. Zvisinei, iyo T2 yebhatiri inoshandisa perfluorinated electrolyte inosvika 220.2 ° C (Mufananidzo 1b), iyo inoratidza kuti iyo perfluorinated electrolyte inogona kuvandudza inherent thermal kuchengetedzwa kwebhatiri kusvika pamwero wakati nekuda kwekukwirira kwayo kwekushisa. Sezvo bhatiri richikura, kukosha kweT2 kwebhatiri remagetsi remagetsi rinodonha kusvika 195.2 °C (Mufananidzo 1c). Zvisinei, kukwegura hakukanganisi T2 yebhatiri uchishandisa perfluorinated electrolytes (Mufananidzo 1d). Pamusoro pezvo, huwandu hwe dT/dt hunokosha hwebhatiri rinoshandisa electrolyte yechinyakare panguva yeTR hunosvika 113°C s-1, ukuwo bhatiri rinoshandisa perfluorinated electrolyte rinongoita 32°C s-1. Musiyano uri muT2 wemabhatiri ekuchembera unogona kuverengerwa nekudzikama kwekupisa kwekunakidzwa kweNMC811, iyo yakaderedzwa pasi peyakajairwa maelectrolyte, asi inogona kunyatso chengetwa pasi peperfluorinated electrolytes.

Mufananidzo 2 Thermal kugadzikana kwe delithiation NMC811 yakanaka electrode uye NMC811/Gr bhatiri musanganiswa. (A,b) Mamepu eContour eC-NMC811 uye F-NMC811 synchrotron high-energy XRD uye inoenderana (003) diffraction peak shanduko. (c) Kudziya uye kuburitsa okisijeni maitiro eiyo yakanaka electrode yeC-NMC811 uye F-NMC811. (d) DSC curve yemuenzaniso musanganiswa wekunakidzwa kwakanaka kwe electrode, lithiated negative electrode, uye electrolyte.

Figures 2a uye b inoratidza HEXRD macurves ekufadza NMC81 ane akasiyana CEI layer muhupo hwezvakajairwa maelectrolyte uye mukati menguva kubva mukamuri tembiricha kusvika 600°C. Zvigumisiro zvinoratidza zvakajeka kuti pamberi pe electrolyte, yakasimba CEI layer inobatsira kugadzikana kwekupisa kwe lithiamu-deposited cathode. Sezvinoratidzwa mumufananidzo 2c, imwe F-NMC811 yakaratidza inononoka exothermic peak pa233.8°C, ukuwo C-NMC811 exothermic peak yakaonekwa pa227.3°C. Pamusoro pezvo, kusimba uye mwero wekuburitswa kweokisijeni kunokonzerwa nechikamu chekuchinja kweC-NMC811 yakanyanya kuoma kupfuura iyo yeF-NMC811, ichienderera ichisimbisa kuti yakasimba CEI inovandudza inherent thermal kugadzikana kweF-NMC811. Mufananidzo 2d inoita DSC bvunzo pamusanganiswa wekunakidzwa NMC811 uye zvimwe zvinoenderana nebhatiri zvikamu. Kune akajairwa maelectrolyte, iwo exothermic peaks emasamples ane 1 uye 100 cycles anoratidza kuti kuchembera kwechinyakare interface kunoderedza kugadzikana kwekupisa. Kusiyana neizvi, kune perfluorinated electrolyte, mifananidzo mushure me1 uye 100 cycles inoratidza yakafara uye yakapfava exothermic peaks, zvinoenderana neTR trigger tembiricha (T2). Mhedzisiro (Mufananidzo 1) inowirirana, zvichiratidza kuti CEI yakasimba inogona kunyatso kuvandudza kugadzikana kwekupisa kwevakwegura uye vanofara NMC811 nezvimwe zvikamu zvebhatiri.

Mufananidzo 3 Hunhu hwekunakidzwa kweNMC811 yakanaka electrode mune perfluorinated electrolyte. (ab) Muchinjikwa-sectional SEM mifananidzo yevakuru F-NMC811 yakanaka electrode uye inoenderana EDS mepu. (ch) Element distribution. (ij) Cross-sectional SEM mufananidzo wechembere F-NMC811 yakanaka electrode pane chaiyo xy. (km) Kuvakwazve kwe3D FIB-SEM chimiro uye kugoverwa kwenzvimbo yeF element.

Kusimbisa kudzoreka kuumbwa kwefluorinated CEI, muchinjika-chikamu morphology uye element kugovera kwechembere NMC811 yakanaka electrode yakadzoserwa muiyo chaiyo-soft-pack bhatiri yakaratidzirwa neFIB-SEM (Mufananidzo 3 ah). Mune perfluorinated electrolyte, yunifomu fluorinated CEI layer inoumbwa pamusoro peF-NMC811. Mukupesana, C-NMC811 mune yakajairika electrolyte inoshaya F uye inoumba isina kuenzana CEI layer. Iyo F element yemukati memuchinjiko-chikamu cheF-NMC811 (Mufananidzo 3h) yakakwira kupfuura iyo yeC-NMC811, izvo zvinoramba zvichiratidza kuti in-situ kuumbwa kweiyo inorganic fluorinated mesophase ndiyo kiyi yekuchengetedza kugadzikana kwekufara kweNMC811. . Nerubatsiro rweFIB-SEM uye EDS mepu, sezvakaratidzwa muFigure 3m, yakacherechedza zvinhu zvakawanda zveF mumuenzaniso we3D pamusoro peF-NMC811.

Mufananidzo 4a) Element kudzika kugovera pamusoro peiyo yekutanga uye inofadza NMC811 yakanaka electrode. (ac) FIB-TOF-SIMS iri kupuruzira kugovera kweF, O, uye Li zvinhu mune yakanaka electrode yeNMC811. (df) Iyo yepamusoro morphology uye kudzika kugovera kweF, O, uye Li zvinhu zveNMC811.

FIB-TOF-SEM yakawedzera kuburitsa kudzika kugoverwa kwezvinhu pamusoro peiyo yakanaka electrode yeNMC811 (Mufananidzo 4). Kuenzaniswa neyekutanga uye C-NMC811 samples, kuwedzera kukuru kwechiratidzo cheF kwakawanikwa muchikamu chepamusoro cheF-NMC811 (Mufananidzo 4a). Mukuwedzera, iyo isina simba yeO uye yakakwirira Li zviratidzo pamusoro pepamusoro inoratidza kuumbwa kweF- uye Li-rich CEI layers (Mufananidzo 4b, c). Mhedzisiro iyi yese yakasimbisa kuti F-NMC811 ine LiF-hupfumi CEI layer. Kuenzaniswa neECI yeC-NMC811, iyo CEI layer yeF-NMC811 ine zvimwe F uye Li zvinhu. Mukuwedzera, sezvinoratidzwa muFIGS. 4d-f, kubva pakuona kweiyo ion etching kudzika, chimiro cheNMC811 chepakutanga chakasimba kupfuura icho cheNMC811 inofadza. Iyo etch kudzika kwechembere F-NMC811 idiki pane C-NMC811, zvinoreva kuti F-NMC811 ine yakanakisa dhizaini kugadzikana.

Mufananidzo 5 CEI kemikari yakagadzirwa pamusoro peiyo yakanaka electrode yeNMC811. (a) XPS spectrum yeNMC811 yakanaka electrode CEI. (bc) XPS C1s uye F1s spectra yepakutanga uye inonakidza NMC811 yakanaka electrode CEI. (d) Cryo-transmission electron maikorosikopu: element distribution yeF-NMC811. (e) Yakaomeswa TEM mufananidzo weCEI wakaumbwa paF-NMC81. (fg) STEM-HAADF uye STEM-ABF mifananidzo yeC-NMC811. (hi) STEM-HAADF uye STEM-ABF mifananidzo yeF-NMC811.

Vakashandisa XPS kuratidza kemikari yeECI muNMC811 (Mufananidzo 5). Kusiyana neyekutanga C-NMC811, iyo CEI yeF-NMC811 ine hombe F neLi asi diki C (Mufananidzo 5a). Kudzikiswa kwemarudzi eC kunoratidza kuti LiF-rich CEI inogona kuchengetedza F-NMC811 nekudzikisa kuenderera kudivi kuita nema electrolytes (Mufananidzo 5b). Pamusoro pezvo, zvidiki zveCO neC=O zvinoratidza kuti solvolysis yeF-NMC811 ishoma. Muiyo F1s spectrum yeXPS (Mufananidzo 5c), F-NMC811 yakaratidza chiratidzo chine simba cheLiF, ichisimbisa kuti CEI ine huwandu hukuru hweLiF inotorwa kubva kune fluorinated solvents. Mamepu eiyo F, O, Ni, Co, uye Mn zvinhu munzvimbo yenzvimbo pane F-NMC811 zvimedu zvinoratidza kuti iwo mamepu akagovaniswa zvakaenzana sese (Mufananidzo 5d). Iyo yakaderera-tembiricha yeTEM mufananidzo muFigure 5e inoratidza kuti CEI inogona kuita senge inodzivirira kuti ivhare zvakafanana NMC811 yakanaka electrode. Kuenderera mberi kusimbisa kushanduka kwechimiro chechimiro, yakakwira-angle denderedzwa yakasviba-munda scanning transmission electron microscopy (HAADF-STEM uye denderedzwa inopenya-munda scanning transmission transmission electron microscopy (ABF-STEM) kuyedza kwakaitwa. -NMC811), The surface of the circulating positive electrode yakachinja zvakanyanya phase, and disordered rock salt phase inounganidzwa pamusoro pepopositive electrode (Figure 5f) Paye electrolyte perfluorinated, pamusoro peF-NMC811 Positive electrode inochengetedza dhizaini (Figure 5h), ichiratidza kukuvadza Chikamu chinova chadzvanywa zvinobudirira.Kuwedzera, yunifomu yeECI layer yakaonekwa pamusoro peF-NMC811 (Figure 5i-g) Migumisiro iyi inowedzera kuratidza kufanana kweiyo CEI layer pane yakanaka electrode pamusoro peNMC811 mune perfluorinated electrolyte.

Mufananidzo 6a) TOF-SIMS spectrum ye interphase phase pamusoro peNMC811 yakanaka electrode. (ac) Kuongorora kwakadzama kwezvimedu zveiyoni yechipiri pane yakanaka electrode yeNMC811. df

C2F-zvimedu zvinowanzoonekwa sezvisikwa zveECI, uye LiF2- uye PO2-zvimedu zvinowanzoonekwa sezvipenyu. Zviratidzo zvakasimbiswa zvakanyanya zveLiF2- uye PO2- zvakawanikwa mukuyedza (Mufananidzo 6a, b), zvichiratidza kuti CEI layer yeF-NMC811 ine huwandu hukuru hwezvipenyu. Zvakasiyana, iyo C2F-chiratidzo cheF-NMC811 haina kusimba pane iyo yeC-NMC811 (Mufananidzo 6c), zvinoreva kuti iyo CEI layer yeF-NMC811 ine zvisikwa zvisingaite zvisina kusimba. Imwe tsvagiridzo yakawanikwa (Mufananidzo 6d-f) kuti kune mamwe marudzi ezvisikwa muECI yeF-NMC811, nepo kune mashoma emhando yemhando muC-NMC811. Zvese izvi mhedzisiro zvinoratidza kuumbwa kweiyo yakasimba inorganic-yakapfuma CEI layer mune perfluorinated electrolyte. Kuenzaniswa neNMC811/Gr yakapfava-pack bhatiri uchishandisa yechinyakare electrolyte, kuvandudzwa kwekuchengetedza bhatiri resoft-pack uchishandisa perfluorinated electrolyte inogona kunzi: Chekutanga, kuumbwa kwe-in-situ kweCEI layer yakapfuma inorganic LiF kunobatsira. The inherent thermal stability of the enjoyed NMC811 positive electrode inoderedza kusunungurwa kwelattice oxygen kunokonzerwa ne phase transition; chechipiri, iyo yakasimba inorganic CEI inodzivirira layer inodzivirira iyo yakanyanya reactive delithiation NMC811 kubva pakubata electrolyte, ichideredza exothermic side reaction; chechitatu, The perfluorinated electrolyte ane yakakwirira kupisa kugadzikana panguva tembiricha.

Mhedziso uye Outlook

Iri basa rakashuma kugadzirwa kweiyo inoshanda Gr/NMC811 homwe-mhando yebhatiri yakazara uchishandisa perfluorinated electrolyte, iyo yakanyanya kunatsiridza kuchengetedzwa kwayo. Intrinsic thermal stability. Chidzidzo chakadzama cheTR inhibition mechanism uye kuwirirana pakati pezvinhu uye mazinga ebhatiri. Kuchembera hakukanganise tembiricha yeTR trigger (T2) yeperfluorinated electrolyte bhatiri panguva yedutu rose, iro rine mabhenefiti ari pachena pamusoro pebhatiri rekuchembera uchishandisa chinyakare electrolyte. Mukuwedzera, iyo exothermic peak inopindirana nemigumisiro yeTR, zvichiratidza kuti CEI yakasimba inobatsira kugadzikana kwekushisa kwe lithiamu-free positive electrode nezvimwe zvikamu zvebheteri. Mhedzisiro iyi inoratidza kuti in-situ control dhizaini yeyakagadzika CEI layer ine yakakosha kutungamira kukosha kwekushandisa kunoshanda kwemabhatiri e-lithium akachengeteka ane simba.

Ruzivo rwezvinyorwa

In-Yakavakwa Ultraconformal Interphases Inogonesa Yakakwira-Kuchengetedzeka Inoshanda Lithium Mabhatiri, Simba Rekuchengetedza Zvishandiso, 2021.