```html
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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 In Hyuk Son Jong Hwan Park Seongyong Park Kwangjin Park Sangil Han Jaeho Shin Seok-Gwang Doo Yunil Hwang Hyuk Chang Jang Wook Choi Isishwankathelo Ukuphucula enye ipropati ngaphandle kokuyeka ezinye kunzima kwiibhetri ze-lithium-ion ngenxa yendlela yokurhweba phakathi kweeparameter eziphambili. Apha sixela inkqubo yokuhanjiswa kwe-graphene–silica, ebizwa ngokuba yi-graphene ball. Isakhiwo sayo esinobukhulu obuthathu kunye neziko le-silicon oxide nanoparticle livumela naku-1 wt% ye-graphene ball ukuba igutyungelwe ngokulinganayo kwi-nickel-rich layered cathode ngeNobilta milling. Ukuququda kwe-graphene-ball kuphucula ubomi besekethe kunye nokukwazi ukutshaja ngokukhawuleza ngokuthintela iziphumo ezingezizo kunye nokubonelela ngeendlela ezisebenzayo zokugcina. I-graphene ball ngokwayo ikwasetyenziswa njengomathuba wokukhuthaza anemathuba aphezulu angama-716.2 mAh g−1. I-full-cell equka i-graphene balls yandisa ubungakanani begazi ngenxa yomthamo nge-27.6% xa ithelekiswa nesekethe elawulayo ngaphandle kwe-graphene balls, ibonisa ukubakho kokufumana i-800 Wh L−1 kwisetingi yesekethe yorhwebo, kunye ne-78.6% yokugcina amandla emva kwesekethe ezingama-500 kwi-5C kunye ne-60 °C. Isingeniso Ukuqhubela phambili kophuhliso lwee-lithium-ion batteries (LIBs) kuye kwazisa ukuphucuka okumangalisayo kwiinkalo ezahlukeneyo zokusebenza kwazo, kubandakanya ubungakanani begazi, ubungakanani bamandla, ubomi besekethe, kunye nokhuseleko. Ngoku, izixhobo ze-IT eziphathwayo zibonelela ngeenkalo ezininzi zezicelo ze-LIB, apho imilinganiselo yokusebenza ye-LIBs zangoku zihlala ziyanelisa , , . Nangona kunjalo, njengoko izithuthi zombane (EVs) ziye zangeniswa kwiimarike ze-LIB, iipropati eziphambili zombane ziye zabeka imilinganiselo enzima ngakumbi; ngelixa ubungakanani begazi obuphezulu bufuna ukunyuswa komthamo wokukhuthaza, i-kinetics ekuphuculweyo ibalulekile ukutshaja ngokukhawuleza kunye nokusebenza okuphezulu. Ukhuseleko ngokuqinisekileyo luyinto ebalulekileyo kwizicelo ze-EV. Umngeni omkhulu ufumaneka ekoyiseni ubudlelwane bokutshintshiselana phakathi kwezi propati ziphambili; ngokuqhelekileyo akunakwenzeka ukuphucula enye ipropati ngaphandle kokuyeka ezinye. 1 2 3 Ubuhlobo bokutshintshiselana bucacile phakathi kobungakanani begazi kunye nokutshaja ngokukhawuleza (okanye ubuchule bamandla). Ngelixa ukusetyenziswa kwe-nanomaterials njengezithako ezisebenzayo ,  kunye nokubandakanya i-carbon nanomaterials , ,  njengeearhente zokugcina ziye zabonisa ukutshaja okuphezulu ngokunciphisa ibala lokuhambisa i-ion kunye ne-resistance yangaphakathi, uninzi lwezi ndlela lusadinga ukuphuculwa ngaphambi kokuba zisebenziseke kubuchwepheshe be-LIB yangoku. I-tap-densities ye-nanomaterials ngaphantsi kwezixhobo eziqhelekileyo, eziyimiphumo embi kubungakanani begazi, obubalulekileyo kwizicelo ezininzi ze-LIB kune-gravimetric counterpart. Kulo mkhwa ofanayo wokunciphisa i-resistance yangaphakathi, ukudityaniswa kwe-carbon nanomaterials njenge-graphene kuye kwabonakala kuluncedo ekwandiseni uburhawu bokugcina be-electrodes zesekethe. Nangona kunjalo, ukufumana ulwabiwo olulinganayo lwemali encinci (oko kukuthi, <3 wt%) ye-carbon nanomaterials kwinkqubo enkulu ye-slurry kusekho ukuba ibonakaliswe. Ukulungiswa kwezinto ezisebenzayo ezikhoyo nge-doping enezinto zangaphandle ,  okanye ulawulo lwe-stoichiometric , ,  kunokwandisa i-diffusivity ye-Li ions kwaye ke ngoko izinga lokutshaja kwezixhobo ezisebenzayo eziqhelekileyo ezine-micrometer dimensions. Uninzi lwezi ndlela, nangona kunjalo, lusebenza ngokufuna amandla ethile. 4 5 6 7 8 9 10 11 12 13 Ngaphezu koko, ngaphandle kobungakanani begazi kunye nokutshaja ngokukhawuleza, ukufumana ubomi obude besekethe, ngakumbi kubushushu obuphezulu (oko kukuthi, 60 °C), kusekho kuyingozi kwi-LIBs eziphuculweyo ezibandakanya izinto ze-electrode ezinomthamo ophezulu. Ngelixa i-nickel (Ni)-rich kunye ne-Li-rich layered oxide materials zithathwa njengezinto zekhathode ezizayo ngenxa yamandla abo aphezulu xa kuthelekiswa ne-classical LiCoO2 counterparts, kuyaziwa ukuba i-cation-mixing engenakuphethengelwa ngexesha lokutshaja yenza umonakalo kwi-layered framework ukuya kwizakhiwo ze-spinel okanye i-rock-salt, kunye neziphumo ezingafunekiyo kumphezulu we-electrode. Ukuthatha ingqalelo imizamo eyenziweyo de kube ngoku, enye yezona zisisombululo zinomdla zokufumana ngokukhawuleza ukutshaja izinto zekhathode ezinomthamo ophezulu ngelahleko encinci kubungakanani begazi kunye nobomi besekethe ibandakanya ukufumana izinto ezikhuselayo ezizilungelelanayo ezinokugutyungelwa ngokulinganayo kwizinto ezisebenzayo ngomthamo omncinci. Apha sixela i-graphene–silica (SiO   ) assembly, ebizwa ngokuba yi-graphene ball (GB), njengento yokugquma yezinto zekhathode eziphambili ze-Ni-rich ezisebenzayo kunye nemathuba ebhetele kwi-LIB. I-GB nganye iqukethe isiko le-SiO   nanoparticle kunye neenqanaba ze-graphene ezijikelezayo, ezakha isakhiwo esinemibala emithathu (3D). Ii-nanoparticles ze-SiO   zidlala indima ebalulekileyo kwiinkalo ezininzi, njengokuthintela ukwakhiwa kwenqanaba le-silicon carbide (SiC) kwi-interface ye-SiO   –graphene ngexesha lokukhula kwe-graphene, ukuqinisekisa ukugubungela okulungileyo kwe-GB kwisithako sekhathode, kunye nokubonelela ngamathuba aphezulu athile xa i-GB isetyenziswa njengomathuba wokukhuthaza. Ukugubungela okulunge ngqo kwe-GB kwikathode ye-Ni-rich layered kuphucula ukuzinza kwe-interfacial kunye ne-electrolyte kunye ne-conductivity yombane kwi-electrode, kuphucula kakhulu ukubuyiselwa kwesekethe kunye nokukwazi ukutshaja ngokukhawuleza kwekhathode. Ukuthatha ii-nzuzo ezizodwa ze-GB, i-full-cell equka ikhathode egutyungelwe nge-GB kunye ne-anode ye-GB ibonisa ukubakho kobungakanani begazi obuphezulu obumalunga ne-800 Wh L−1 kwimeko yesekethe yorhwebo, kunye nokugcinwa kwamandla okuyi-78.6% emva kwesekethe ezingama-500 kwi-5C kunye ne-60 °C. x x x x Iziphumo Ukwakhiwa kwe-graphene ball Ukuze kwenziwe i-GB eyi-popcorn, sivelise inkqubo yokuhanjiswa kwe-graphene (CVD) yokukhula kwe-graphene. Igasa le-CH4 lalitsalwa kwi-furnace kunye ne-SiO2 nanoparticles enemilo engama-20–30 nm kwi-1000 °C. Ngeli qondo lobushushu, i-CH4 iyatyekwa ukwenza ii-athomu ze-hydrogen, ezinokuthi kamva zikwazi ukunciphisa i-SiO2 kwi-SiO   (  lt; 2). I-OH− ikwaveliswa ngaxeshanye ngokusebenzisa le rection elandelayo: x x Into ephambili kule rection kukuba i-SiO   enekhonza njengeendawo zokukhuthaza ukukhula kwe-graphene, kwaye i-OH− ikwasetyenziswa njengento elawulayo yokulawula ukwenziwa kwe-carbon elawulayo ukuya kwi-graphene , . Indima yeearhente ezilawulayo ekwenziweni kwe-carbon elawulayo iye yachazwa kutshanje  ngendlela, ngaphandle kweearhente ezilawulayo, ukwenziwa kwe-carbon amorphous kunobudlelwane obuninzi. Nangona kunjalo, xa kukho i-arhente elawulayo, kuye kwafunyaniswa ukuba i-rection yokwenziwa kwe-CO okanye i-CO2 iyathandwa kwi-athomu zekhonkco ezingaba ziye zavelisa i-carbon amorphous. Ngapha koko, ukukhula okulula kwe-graphene kusetyenziswa ii-catalysts zemithombo kuyaziwa ukwenzeka ngendlela efanayo , , , apho i-oxygen eseleyo kumphezulu wemithombo ibangela ukuthandwa kwe-reaction ukuya kwenziwa kwe-graphitic carbon. Ubukho be-arhente elawulayo buthintela ukwenziwa kwenqanaba le-silicon carbide (SiC) kumphezulu we-SiO   ngenxa yokuba i-arhente ithintela ukuncitshiswa kwe-Si ukuya ekwenziweni kwe-SiC . x 14 15 16 17 18 19 x 19 Kwindlela yethu yokusebenza esekelwe ekusetyenzisweni kwe-CH4 kuphela, kwiibanga lobushushu ngaphantsi kwe-900 °C, i-graphene yenyuka kancinci. Ngokungafaniyo, kwi-1050 °C nangaphezulu, ukukhula kwe-graphene kwaba kukhulu kakhulu ukuya ekwenziweni kwe-graphite (Supplementary Fig.  ). Ngokukhethekileyo, ubushushu bokukhula be-1000 °C bungaphantsi kunezo (1100–1400 °C) zihlala zisetyenziselwa ukukhula kwe-graphene esekelwe kwi-CVD esekelwe kwi-Si kunye ne-SiO2 substrates ngaphandle kwee-catalysts zemithombo , , . Indima ebalulekileyo yendlela yokukhula ichazwe ngokuvavanya okulawulayo (Supplementary Fig.  ); ngokulandela iinkqubo zesiqhelo ze-CVD ezisebenzisa ii-catalysts zemithombo, i-CH4 kunye ne-H2 zalitsalwa kwisilinganiselo sokuhamba kwe-volumetric ye-3:7 kwi-1000 °C. Ngenxa yokuba ukutshatyalaliswa kwe-CH4 kwathintelwa bubungakanani obukhulu be-H2, ukukhula kwe-graphene kwakucothisa kakhulu, kubonisa ukubaluleka kokusetyenziswa kwe-CH4 kuphela ekukhuleni okusebenzayo kwe-graphene kwinkqubo yethu yokwakha. Ngokubanzi, ukukhethwa kwezixhobo zokusebenza kunye ne-reaction temperature kwisikimu se-reaction sangoku siyahluka kwi-CVD counterparts ezidlulileyo ezisebenzisa ii-catalysts zemithombo kwaye idlala indima ebalulekileyo ekuveliseni i-graphene–SiO   assembly kunye nesakhiwo esinemibala emithathu. 1 20 21 22 2 x Ubukhakha bokuhlola nge-scanning electron microscope (SEM) (Supplementary Fig.  ) kunye ne-transmission electron microscope (TEM) (Fig.  ) ezenziwe ngexesha lenkqubo ye-CVD zibonisa utshintsho ekukhuleni nasekujongeni kwe-graphene. Emva kwemizuzu emi-5 yenkqubo ye-CVD, ifilimu ye-graphene enamaqhekeza ama-2–3 ayibonwa ngokucacileyo kumphezulu we-SiO2 (Fig.  , e), kunye nombala wombala uguquka ube mnyama (Supplementary Fig.  ). Ukukhula kwe-graphene kwaba kubonakala ngakumbi emva kwemizuzu engama-30 yenkqubo ye-CVD, apho isakhiwo se-3D sheet sasi bonakala kakhulu (Fig.  , f). Umfanekiso we-TEM ophezulu (Fig.  ) ubandakanya ubume be-athomu be-hexagonal kwicandelo le-graphene, elibonisa inqanaba layo eliphambili. Emva kwemizuzu engama-30, kwakukwa kuphawuliwe ukuba ubungakanani be-SiO2 nanoparticles bancipha ukusuka kuma-28.2 ukuya kuma-15.3 nm ngesilinganiso (Supplementary Fig.  ). Oku kwenzeka ngenxa yokuba ukukhula kwe-graphene kubandakanya ukuncitshiswa kwe-SiO2 okukhankanywe ngasentla kunye nokwenziwa kwe-OH− emva koko. Ngoko ke, ukukhula konke kwe-graphene kufana nokudubula kwe-popcorn kwisakhiwo esinobukhulu obuthathu, esiveliswe ngamakhondo emvelaphi (Fig.  ). 3a–f 1a–g 1b 3g 1c 1g 4 1h   Ukukhula kwe-Graphene ukusuka kwi-SiO2 nanoparticles.  –  Uhlolo lwe-TEM   ngaphambi kokukhula kwe-CVD,   emva kwemizuzu emi-5 yokukhula, kunye   emva kwemizuzu engama-30 yokukhula (imilinganiselo yeebala, 50 nm).  –  Imifanekiso yabo eneenkcukacha (imilinganiselo yeebala, 10 nm).   Umboniso ophezulu we-graphene emva kwemizuzu engama-30 yokukhula kunye nembono yayo yobude-athomu ukusuka kwibala elimhlophe (ifakwe) (umlinganiselo webhala, 2 nm).   Ukudweba okufanekisayo kokukhula kwe-graphene eyi-popcorn ukusuka kwi-SiO2 nanoparticles a c a b c d f g h Ukukhula kwe-graphene kuye kwachazwa ngokugqithisileyo nge-series ye-analyses eyongezelelweyo. Ii-spectra ze-X-ray diffraction (XRD) ezifunyenwe ngexesha lokukhula zibonisa ukuba njengoko inkqubo ye-CVD iqhubela phambili, ii-peaks kwi-2  = 26.44° kunye ne-44°, ezihambelana neenqanaba (002) kunye ne-101) ze-graphite, zakhula ngokuqhubekayo (Fig.  ), zixhasa kwakhona ukwenziwa kwe-graphitic carbon , , . Ukukhula kwe-graphene kwakukwakubonakaliswa kwi-peaks kwi-284.5 kunye ne-291.5 eV kwi-branch ye-C 1s ye-X-ray photoelectron spectroscopy (XPS) analysis (Fig.  ) , . I-peak kwi-284.5 eV inikezelwe kwi-C–C kunye ne-C = C bonds, ezavela ngokucacileyo emva kwemizuzu engama-30 yokukhula ngenxa yokwenziwa kwe-graphitic carbon. Ii-peaks ze-XPS eziqhubekayo kwi-branch ye-Si 1s ye-XPS analysis (Fig.  ) ziqinisekisa kwakhona  ukuncitshiswa kwe-SiO2 ngexesha lenkqubo ye-CVD. Ngokwanda kwexesha lokukhula, i-peak ejikeleze i-103 eV yafudukela kumaxesha okubophela asezantsi ngenxa yokuncipha kwenqanaba lokufaka i-oxygen kwi-Si. Ngokusekelwe kubukho kunye nobukhulu besiginali yekhonkco kwi-energy dispersive X-ray (EDX) mapping (Fig.  ), kwafunyaniswa ukuba nokuba emva kwemizuzu emi-5, ukukhula kwe-graphene kwenzeke kumphezulu we-SiO   , kwaye emva kwemizuzu engama-30, ukukhula kwaba kwiindawo ezibanzi zomboniso, ngelixa i-Si kunye ne-O zahlala zisasazwe ngokulinganayo. Imali enobunzima ye-graphene, kunye neziphumo zohlalutyo lweRaman, umthamo othile womphezulu, kunye nokugcinwa kwe-GB kwi-CVD yokukhula eyahlukileyo ixhatshazelwe kwiThebhile . Ngokubhekiselele kumthamo othile womphezulu, ukuncipha kwayo ngokwanda kwexesha lokusebenza kunxulumene ne-graphitization eqhubekayo apho iinqanaba ze-graphene zidityaniswe kwaye zibekwe phezu kwazo. Ubutyhakha obuneenkcukacha beRaman kunye ne-thermogravimetric (TG) analyses spectra ziboniswa kwi-Supplementary Fig.  . θ 2a 23 24 25 2b 22 23 2c 25 2d–g x 1 5   Uhlalutyo lwe-graphene-ball ngexesha lokukhula kwayo.  –  Ukubeka iliso ekukhuleni kwe-graphene ngexesha lenkqubo ye-CVD kusetyenziswa   XRD,   XPS kwi-C 1s branch, kunye   XPS Si 2p branch.  –  I-EDX elemental mapping ngokubhekisele kwi-C, O, kunye ne-Si emva kwe  ,   imizuzu emi-5 kunye  ,   imizuzu engama-30 yokukhula kwe-graphene ukusuka kwi-SiO2 (imilinganiselo yeebala, 50 nm) a c a b c d g d e f g Ukugubungela i-graphene ball kwisithako sekhathode se-nickel-rich Ngenxa yomhlaba wayo wokwakheka kwe-atom-thick, i-graphene iye yacingwa njengeyona nto ilungileyo yokugquma umphezulu wezinto zekhathode ezinomthamo ophezulu. Nangona kunjalo, kwimeko yezi nkqubo zombini ezaziwayo , , ,  ezisekelwe kwindlela kaHummer, ukufumana ukugubungela okulinganayo ngomthamo olinganiselweyo we-graphene akunakwenzeka ngenxa yokuhlangana, okubangelwa yinto yokusebenzisana ye-electrostatic phakathi kweengqimba ze-graphene. Ngomzamo wokoyisa ingxaki yokuhlangana, enye indlela, njengokuqhekeka kwe-graphite kusetyenziswa inkqubo yokuhlanganisa ibhola, iye yaveliswa . Nangona kunjalo, le nkqubo ihlala icothisa (> 6h) kwaye, okubaluleke ngakumbi, ingalimaza ubuchule be-crystal yesithako sosingathi. Kufanele kuphawulwe ukuba ukugquma kwe-carbon amorphous ngeenkqubo ze-CVD akunakusebenza kwizinto ze-oxide eziphambili ze-Ni ,  ngenxa yokuba iinkqubo ze-CVD zikhupha iimithombo ze-transition (TMs), ziphazamisa ubume be-crystal yokuqala yesithako sosingathi. 26 27 28 29 30 31 32 Ngokungafaniyo, i-GB eyenziweyo kulo sifundo ingagqunywa kumphezulu we-LiNi0.6Co0.1Mn0.3O2 powder (ubungakanani = ~10 µm) ngomthamo omncinci we-1 wt% ngeNobilta milling process elula. Inkqubo yokugquma ikwakhawuleza kakhulu (~10 min kwi-3000 rpm). Ii-seeds ze-SiO&

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