ESM: Gina-in-sa-in-sa-in-da-daidaita-hanyar keɓaɓɓiyar keɓancewa na electrolyte perfluorinated don aikace-aikacen batirin lithium mai ƙarfi mai ƙarfi

Binciken Bincike

A cikin batirin lithium-ion, don cimma burin 350 Wh Kg-1, kayan cathode suna amfani da sinadarin nickel-rich Layered oxide (LiNixMnyCozO2, x+y+z=1, wanda ake kira NMCxyz). Tare da karuwar yawan kuzari, haɗarin da ke da alaƙa da zafin zafi na LIBs sun ja hankalin mutane. Ta fuskar abu, ingantattun na'urorin lantarki masu arzikin nickel suna da matsala mai tsanani na aminci. Bugu da ƙari, oxidation/crosstalk na sauran abubuwan haɗin baturi, irin su ruwayen ruwa da na'urorin lantarki mara kyau, kuma na iya haifar da guduwar zafi, wanda ake la'akari da babban dalilin matsalolin aminci. Samuwar in-wurin da za a iya sarrafa shi na tsayayyen tsarin lantarki-electrolyte shine dabarun farko don ƙarni na gaba na manyan batura masu ƙarfi-yawan tushen lithium. Musamman ma, ƙaƙƙarfan ƙaƙƙarfan ƙaƙƙarfan ƙaƙƙarfan katode-electrolyte interphase (CEI) tare da mafi girman kwanciyar hankali na inorganic na iya magance matsalar tsaro ta hana sakin iskar oxygen. Ya zuwa yanzu, akwai ƙarancin bincike kan abubuwan da aka gyara na CEI cathode da amincin matakin baturi.

Nunin nasara

Kwanan nan, Feng Xuning, Wang Li, da Ouyang Minggao na Jami'ar Tsinghua sun buga takardar bincike mai suna "In-Built Ultraconformal Interphases Enable High-Safety Practical Lithium Battery" akan Kayan Ajiye Makamashi. Marubucin ya kimanta aikin aminci na NMC811/Gr cikakken batir mai laushi mai laushi da kwanciyar hankali na madaidaicin CEI tabbataccen lantarki. An yi nazari sosai dalla-dalla dalla-dalla tsarin hana gudu na zafi tsakanin kayan da baturi mai laushi. Ta yin amfani da electrolyte maras ƙonewa, an shirya cikakken nau'in jakar NMC811/Gr. An inganta kwanciyar hankali na thermal na NMC811 ta wurin da aka kafa CEI mai kariya mai wadata a cikin LiF mara kyau. CEI na LiF na iya sauƙaƙe sakin iskar oxygen da canjin lokaci ya haifar kuma ya hana haɓakar haɓakawa tsakanin NMC811 mai farin ciki da mai walƙiya mai walƙiya.

Jagorar hoto

Hoto 1 Kwatanta halayen gudu na thermal na NMC811/Gr cikakken nau'in jakar jaka ta amfani da electrolyte perfluorinated da na al'ada electrolyte. Bayan zagayowar al'ada guda ɗaya (a) EC/EMC da (b) gurɓataccen jakar lantarki FEC/FEMC/HFE nau'in cikakken batura. (c) Na al'ada EC/EMC electrolysis da (d) perfluorinated FEC/FEMC/HFE electrolyte jakar-nau'in cikakken baturi shekaru bayan 100 hawan keke.

Don baturin NMC811/Gr tare da electrolyte na gargajiya bayan zagaye ɗaya (Hoto 1a), T2 yana a 202.5°C. T2 yana faruwa lokacin da buɗaɗɗen wutar lantarki ya faɗi. Duk da haka, T2 na baturi ta amfani da perfluorinated electrolyte ya kai 220.2 ° C (Hoto 1b), wanda ke nuna cewa perfluorinated electrolyte zai iya inganta yanayin yanayin zafi na baturin zuwa wani matsayi saboda girman yanayin zafi. Yayin da baturin ya tsufa, ƙimar T2 na baturin lantarki na gargajiya ya faɗi zuwa 195.2 °C (Hoto 1c). Koyaya, tsarin tsufa baya shafar T2 na baturin ta yin amfani da electrolytes perfluorinated (Hoto 1d). Bugu da kari, matsakaicin ƙimar dT/dt na baturi ta amfani da electrolyte na gargajiya yayin TR ya kai 113°C s-1, yayin da baturin da ke amfani da electrolyte perfluorinated shine kawai 32°C s-1. Bambance-bambance a cikin T2 na batura masu tsufa ana iya danganta su zuwa yanayin kwanciyar hankali na thermal na NMC811 mai daɗi, wanda aka rage a ƙarƙashin electrolytes na al'ada, amma ana iya kiyaye shi da kyau a ƙarƙashin perfluorinated electrolytes.

Hoto 2 Zaman lafiyar zafi na delithiation NMC811 tabbataccen lantarki da cakuda baturi NMC811/Gr. (A,b) Taswirorin kwane-kwane na C-NMC811 da F-NMC811 synchrotron high-makamashi XRD da daidai (003) canje-canje kololuwa. (c) Halin sakin dumama da iskar oxygen na ingantaccen lantarki na C-NMC811 da F-NMC811. (d) DSC lanƙwan samfurin cakuɗen samfurin ingantacciyar wutar lantarki mai daɗi, ƙarancin wutan lantarki, da electrolyte.

Figures 2a da b suna nuna madaidaicin HEXRD na farin ciki NMC81 tare da yadudduka na CEI daban-daban a gaban electrolytes na al'ada da kuma lokacin lokacin daga dakin zafin jiki zuwa 600 ° C. Sakamakon ya nuna a fili cewa a gaban na'urar lantarki, wani kakkarfan CEI mai ƙarfi yana taimakawa ga kwanciyar hankali na thermal na cathode mai ajiyar lithium. Kamar yadda aka nuna a cikin Hoto 2c, F-NMC811 guda ɗaya ya nuna matsakaicin matsakaicin matsakaici a 233.8 ° C, yayin da C-NMC811 exothermic ganiya ya bayyana a 227.3 ° C. Bugu da ƙari, ƙarfin da adadin iskar oxygen da ke haifar da canjin lokaci na C-NMC811 ya fi na F-NMC811, yana kara tabbatar da cewa CEI mai ƙarfi yana inganta ingantaccen yanayin zafi na F-NMC811. Hoto 2d yana yin gwajin DSC akan cakuda NMC811 mai daɗi da sauran abubuwan da suka dace da baturi. Don na al'ada electrolytes, exothermic kololuwa na samfurori tare da 1 da 100 hawan keke nuna cewa tsufa na gargajiya dubawa zai rage thermal kwanciyar hankali. Sabanin haka, ga masu amfani da wutar lantarki, zane-zane bayan 1 da 100 zagayowar suna nuna fa'ida da ƙananan kololuwa, daidai da zafin jiki na TR (T2). Sakamakon (Hoto 1) sun kasance daidai, yana nuna cewa mai ƙarfi CEI zai iya inganta ingantaccen yanayin zafi na tsofaffi da NMC811 da sauran abubuwan baturi.

Hoto 3 Halayen NMC811 tabbataccen lantarki mai daɗi a cikin perfluorinated electrolyte. (ab) Hotunan SEM-tsage-tsalle na tsohuwar F-NMC811 ingantaccen lantarki da taswirar EDS daidai. (ch) Rarraba abubuwa. (ij) Hoton SEM mai tsaka-tsaki na tsohuwar F-NMC811 tabbataccen lantarki akan xy kama-da-wane. (km) Sake gina tsarin 3D FIB-SEM da rarraba sararin samaniya na abubuwan F.

Don tabbatar da tsarin sarrafawa na CEI mai fluorinated, tsarin giciye-ɓangarorin ilimin halittar jiki da rarraba kashi na tsohuwar NMC811 tabbataccen lantarki da aka dawo da su a cikin ainihin baturin fakiti mai laushi an kwatanta su ta FIB-SEM (Hoto 3 ah). A cikin perfluorinated electrolyte, uniform fluorinated CEI Layer aka samu a saman F-NMC811. Akasin haka, C-NMC811 a cikin na'urar lantarki ta al'ada ba ta da F kuma tana samar da layin CEI mara daidaituwa. Abubuwan da ke cikin F a kan sashin giciye na F-NMC811 (Hoto 3h) ya fi na C-NMC811, wanda ya kara tabbatar da cewa samuwar wuri na mesophase inorganic fluorinated mesophase shine mabuɗin don kiyaye kwanciyar hankali na NMC811 mai farin ciki. . Tare da taimakon FIB-SEM da taswirar EDS, kamar yadda aka nuna a cikin Hoto 3m, ya lura da abubuwa da yawa F a cikin samfurin 3D a saman F-NMC811.

Hoto 4a) Rarraba zurfin abubuwan abubuwa a saman asalin asali da jin daɗin NMC811 tabbataccen lantarki. (ac) FIB-TOF-SIM yana watsar da rarraba abubuwan F, O, da Li a cikin ingantaccen lantarki na NMC811. (df) Halin halittar jiki da zurfin rarraba abubuwan F, O, da Li na NMC811.

FIB-TOF-SEM ya kara bayyana zurfin rarraba abubuwa akan farfajiyar ingantaccen lantarki na NMC811 (Hoto 4). Idan aka kwatanta da asali da samfurori na C-NMC811, an sami karuwa mai yawa a cikin siginar F a saman saman saman F-NMC811 (Hoto 4a). Bugu da ƙari, ƙananan sigina na O da manyan Li a saman suna nuna samuwar F- da Li-rich CEI layers (Hoto 4b, c). Waɗannan sakamakon duk sun tabbatar da cewa F-NMC811 yana da ɗigon CEI mai arzikin LiF. Idan aka kwatanta da CEI na C-NMC811, CEI Layer na F-NMC811 ya ƙunshi ƙarin abubuwan F da Li. Bugu da kari, kamar yadda aka nuna a FIGS. 4d-f, daga hangen nesa na ion etching zurfin, tsarin ainihin NMC811 ya fi ƙarfin na NMC811 mai farin ciki. Zurfin etch na tsofaffi F-NMC811 ya fi C-NMC811, wanda ke nufin cewa F-NMC811 yana da kyakkyawan kwanciyar hankali.

Hoto 5 Tsarin sinadarai na CEI akan saman ingantaccen lantarki na NMC811. (a) Bakan XPS na NMC811 tabbataccen lantarki CEI. (bc) XPS C1s da F1s bakan na asali da farin ciki NMC811 tabbataccen lantarki CEI. (d) Cryo-transmission electron microscope: rarraba kashi na F-NMC811. (e) Hoton TEM mai sanyi na CEI da aka kafa akan F-NMC81. (fg) Hotunan STEM-HAADF da STEM-ABF na C-NMC811. (hi) Hotunan STEM-HAADF da STEM-ABF na F-NMC811.

Sun yi amfani da XPS don bayyana sinadarai na CEI a cikin NMC811 (Hoto na 5). Ba kamar ainihin C-NMC811 ba, CEI na F-NMC811 ya ƙunshi babban F da Li amma ƙananan C (Hoto 5a). Rage nau'in C yana nuna cewa LiF-mai arzikin CEI na iya kare F-NMC811 ta hanyar rage ci gaban halayen gefe tare da electrolytes (Hoto 5b). Bugu da ƙari, ƙananan adadin CO da C = O suna nuna cewa solvolysis na F-NMC811 yana da iyaka. A cikin bakan F1s na XPS (Hoto 5c), F-NMC811 ya nuna siginar LiF mai ƙarfi, yana mai tabbatar da cewa CEI ta ƙunshi babban adadin LiF da aka samu daga kaushi mai ƙarfi. Taswirar abubuwan F, O, Ni, Co, da Mn a cikin yanki na gida akan barbashi na F-NMC811 yana nuna cewa an rarraba cikakkun bayanai gaba ɗaya (Hoto 5d). Hoton TEM mai ƙarancin zafin jiki a cikin Hoto 5e yana nuna cewa CEI na iya aiki azaman Layer na kariya don rufe daidaitattun lantarki na NMC811. Don ci gaba da tabbatar da juyin halittar tsarin mu'amala, an gudanar da gwaje-gwajen gwaje-gwajen na'urorin lantarki na lantarki (HAADF-STEM da madauwari mai haske-filin sikanin watsa wutar lantarki (ABF-STEM). -NMC811), Fuskokin da ke zagaya tabbataccen lantarki ya sami canjin yanayi mai tsanani, kuma an tarar da wani ɓarnar gishirin dutsen a saman ingantaccen lantarki (Hoto 5f) Ga madaidaicin electrolyte, saman F-NMC811. tabbataccen lantarki yana kula da tsari mai laushi (Hoto na 5h), yana nuna cutarwa Lokacin yana zama danne yadda yakamata.Bugu da ƙari, an lura da nau'in nau'in nau'in CEI a saman F-NMC811 (Hoto 5i-g) Waɗannan sakamakon sun ƙara tabbatar da daidaiton yanayin CEI Layer a kan tabbatacce lantarki surface na NMC811 a cikin perfluorinated electrolyte.

Hoto 6a) TOF-SIM bakan na tsaka-tsakin lokaci a kan saman NMC811 tabbataccen lantarki. (ac) Bincike mai zurfi na takamaiman gutsuttsura ion na biyu akan ingantaccen lantarki na NMC811. (df) TOF-SIMS nau'in sinadarai na juzu'in ion na biyu bayan 180 seconds na sputtering akan ainihin, C-NMC811 da F-NMC811.

C2F-gutsuniyoyi ana ɗaukarsu gabaɗaya sinadarai na CEI, kuma LiF2- da PO2-gutuwa galibi ana ɗaukar su azaman nau'in inorganic. An sami ingantaccen siginar LiF2- da PO2- a cikin gwajin (Hoto 6a, b), yana nuna cewa layin CEI na F-NMC811 ya ƙunshi adadi mai yawa na nau'in inorganic. Akasin haka, siginar C2F na F-NMC811 ya fi na C-NMC811 (Hoto 6c), wanda ke nufin cewa layin CEI na F-NMC811 ya ƙunshi nau'ikan halittu masu rauni. An sami ƙarin bincike (Hoto 6d-f) cewa akwai ƙarin nau'ikan inorganic a cikin CEI na F-NMC811, yayin da akwai ƙarancin nau'in inorganic a cikin C-NMC811. Duk waɗannan sakamakon suna nuna samuwar ƙaƙƙarfan ƙaƙƙarfan ɗigon CEI mai arziƙin inorganic a cikin ruɓaɓɓen electrolyte. Idan aka kwatanta da NMC811/Gr baturi mai taushin fakiti ta amfani da na'urar lantarki ta gargajiya, ana iya dangana lafiyar fakitin mai taushi ta amfani da electrolyte perfluorinated zuwa: Na farko, a cikin wurin samuwar wani Layer CEI mai wadata a cikin LiF na inorganic yana da fa'ida. Matsakaicin yanayin yanayin zafi na NMC811 tabbataccen lantarki mai daɗi yana rage sakin iskar oxygen da ke haifar da canjin lokaci; na biyu, m inorganic CEI kariya Layer kara hana sosai reactive delithiation NMC811 daga tuntubar da electrolyte, rage exothermic gefen dauki; na uku, The perfluorinated electrolyte yana da high thermal kwanciyar hankali a high yanayin zafi.

Kammalawa da Outlook

Wannan aikin ya ba da rahoton haɓaka ingantaccen nau'in jakar Gr/NMC811 cikakken baturi ta amfani da perfluorinated electrolyte, wanda ya inganta aikin amincin sa sosai. Intrinsic thermal kwanciyar hankali. Bincike mai zurfi na tsarin hanawa na TR da haɗin kai tsakanin kayan aiki da matakan baturi. Tsarin tsufa baya shafar zafin jiki na TR faɗakarwa (T2) na batir ɗin da aka lalatar da shi yayin duk guguwar, wanda ke da fa'ida a bayyane akan batirin tsufa ta amfani da lantarki na gargajiya. Bugu da ƙari, ƙaƙƙarfan ƙuri'a ya yi daidai da sakamakon TR, yana nuna cewa ƙarfin CEI mai ƙarfi yana dacewa da kwanciyar hankali na zafin jiki mai kyau na lithium maras kyau da sauran abubuwan baturi. Waɗannan sakamakon sun nuna cewa ƙirar ƙirar cikin-wuri na barga CEI Layer yana da mahimmancin jagora don aikace-aikacen mafi aminci na batura lithium masu ƙarfi.

Bayanin adabi

In-In-In-Ultraconformal Interphases Yana Ba da Haɓaka Babban Amintaccen Batir Lithium, Kayan Ajiye Makamashi, 2021.