Ithonywe izinga elishisayo lemakethe yezimoto zikagesi,amabhethri e-lithium-ion, njengenye yezingxenye eziyinhloko zezimoto zikagesi, ziye zagcizelelwa ngezinga elikhulu.Abantu bazibophezele ekuthuthukiseni impilo ende, amandla aphezulu, ukuphepha okuhle kwebhethri ye-lithium-ion.Phakathi kwabo, ukuncishiswa kweibhethri ye-lithium-ionumthamo ufanelwe ukunakwa kwawo wonke umuntu, ukuqonda okugcwele kuphela kwezizathu zokuncishiswa kwamabhethri e-lithium-ion noma umshini, ukuze ukwazi ukunikeza umuthi ofanele wokuxazulula inkinga, ukuthi umthamo wamabhethri e-lithium-ion kungani ukunciphisa?
Izizathu zokucekelwa phansi kwamandla amabhethri e-lithium-ion
1.Positive electrode impahla
I-LiCoO2 ingenye yezinto ezisetshenziswa kakhulu ze-cathode (isigaba se-3C sisetshenziswa kakhulu, futhi amabhethri amandla ngokuyisisekelo aphethe i-ternary ne-lithium iron phosphate).Njengoba inani lemijikelezo likhula, ukulahleka kwe-lithium ion esebenzayo kunomthelela omkhulu ekuboleni kwamandla.Ngemuva kwemijikelezo engu-200, i-LiCoO2 ayizange ibe nenguquko yesigaba, kodwa kunalokho ukuguqulwa kwesakhiwo se-lamellar, okuholela ebunzimeni ekushumekeni kwe-Li+.
I-LiFePO4 inokusimama okuhle kwesakhiwo, kodwa i-Fe3+ ku-anode iyancibilika futhi yehlisele ku-Fe metal ku-graphite anode, okuholela ekwandeni kwe-anode polarization.Ngokuvamile ukuchithwa kwe-Fe3+ kuvinjelwa ukumbozwa kwezinhlayiya ze-LiFePO4 noma ukukhethwa kwe-electrolyte.
Izinto ezisetshenziswayo ze-NCM ternary ① Ama-ion ensimbi aguquguqukayo ku-transition metal oxide cathode material kulula ukuncibilika emazingeni okushisa aphezulu, ngaleyo ndlela akhulule i-electrolyte noma idiphozi ohlangothini olunegethivu ibangele ukuncipha kwamandla;② Uma i-voltage ingaphezu kuka-4.4V vs. Li+/Li, ukuguqulwa kwesakhiwo se-ternary material kuholela ekulimazeni umthamo;③ Imigqa exubile ye-Li-Ni, eholela ekuvinjweni kweziteshi ze-Li+.
Izimbangela eziyinhloko zokuwohloka kwamandla kumabhethri e-lithium-ion asekelwe ku-LiMnO4 1. isigaba esingenakuhlehliswa noma izinguquko zesakhiwo, njengokuphambuka kwe-Jahn-Teller;kanye 2. nokuhlakazwa kwe-Mn ku-electrolyte (ukuba khona kwe-HF ku-electrolyte), ukusabela kokungalingani, noma ukuncishiswa ku-anode.
2.Izinto ezingezinhle ze-electrode
Ukukhiqizwa kwemvula ye-lithium ohlangothini lwe-anode lwe-graphite (ingxenye ye-lithium iba "i-lithium efile" noma ikhiqiza i-lithium dendrites), emazingeni okushisa aphansi, ukusabalalisa kwe-lithium ion kuncipha kalula okuholela emvuleni ye-lithium, futhi imvula ye-lithium nayo ijwayele ukwenzeka. lapho isilinganiso se-N/P siphansi kakhulu.
Ukubhujiswa okuphindaphindiwe nokukhula kwefilimu ye-SEI ohlangothini lwe-anode kuholela ekwehliseni i-lithium nokwenyuka kwe-polarization.
Inqubo ephindaphindiwe yokushumeka kwe-lithium/de-lithium ku-anode esekwe ku-silicon ingaholela kalula ekwandiseni ivolumu kanye nokwehluleka kokuqhekeka kwezinhlayiya ze-silicon.Ngakho-ke, nge-silicon anode, kubaluleke kakhulu ukuthola indlela yokuvimbela ukukhuliswa kwevolumu yayo.
3.I-Electrolyte
Izici ku-electrolyte ezinomthelela ekwehleni kwamandlaamabhethri e-lithium-ionzihlanganisa:
1. Ukubola kwezinyibilikisi nama-electrolyte (ukwehluleka okukhulu noma izinkinga zokuphepha ezifana nokukhiqizwa kwegesi), ezincibilikisa izinto eziphilayo, lapho amandla e-oxidation emakhulu kune-5V vs. Li+/Li noma amandla okunciphisa angaphansi kuka-0.8V (i-electrolyte decomposition voltage ehlukile ezahlukene), kulula ukubola.Ku-electrolyte (isb. i-LiPF6), kulula ukubola uma izinga lokushisa liphezulu (ngaphezu kuka-55℃) ngenxa yokungaqini kahle;
2. Njengoba inani lemijikelezo likhula, ukusabela phakathi kwe-electrolyte kanye nama-electrode aqondile kanye nama-negative ayanda, okwenza umthamo wokudlulisa ngobuningi ube buthaka.
4.I-diaphragm
I-diaphragm ingavimba ama-electron futhi igcwalise ukudluliswa kwama-ion.Kodwa-ke, ikhono le-diaphragm lokuthutha i-Li+ liyancishiswa lapho izimbobo ze-diaphragm zivinjwa imikhiqizo yokubola ye-electrolyte, njll., noma lapho i-diaphragm incipha emazingeni okushisa aphezulu, noma lapho i-diaphragm iguga.Ngaphezu kwalokho, ukwakheka kwe-lithium dendrites ebhoboza i-diaphragm eholela kumjikelezo omfushane wangaphakathi kuyisizathu esiyinhloko sokwehluleka kwayo.
5. Ukuqoqa uketshezi
Imbangela yokulahlekelwa amandla ngenxa yomqoqi ngokuvamile ukugqwala komqoqi.Ithusi lisetshenziswa njengomqoqi ongemuhle ngoba kulula ukwenza i-oxidize ngamandla aphezulu, kuyilapho i-aluminium isetshenziswa njengomqoqi omuhle ngoba kulula ukwenza ingxubevange ye-lithium-aluminium ene-lithium ngamakhono aphansi.Ngaphansi kwe-voltage ephansi (ephansi njengo-1.5V nangaphansi, ukuchichima ngokweqile), ithusi likhipha oksijini liye ku-Cu2+ ku-electrolyte bese lifaka phezu kwe-electrode eyinegethivu, ivimbela ukushumeka kwe-lithium, okuholela ekonakaleni komthamo.Futhi ohlangothini oluhle, ukushaja ngokweqile kwe-ibhethrikubangela ukugoba komqoqi we-aluminium, okuholela ekwandeni kokumelana kwangaphakathi kanye nokuwohloka kwamandla.
6. Izici zokushaja nokukhipha
Ukushaja ngokweqile nokukhipha iziphindaphinda kungaholela ekonakaleni komthamo okusheshisiwe wamabhethri e-lithium-ion.Ukwenyuka kwesiphindaphinda sokushaja/sokukhipha kusho ukuthi i-polarization yebhethri ikhuphuka ngokufanele, okuholela ekwehleni komthamo.Ukwengeza, ingcindezi ebangelwa ukusabalalisa ekhiqizwa ukushaja nokudedelwa ngezilinganiso eziphezulu zokuphindaphinda kuholela ekulahlekelweni kwezinto ezisebenzayo ze-cathode kanye nokuguga okusheshayo kwebhethri.
Esimeni sokushajwa ngokweqile kanye nokuchithwa kwamabhethri, i-electrode engeyinhle ijwayele ukuba ne-lithium precipitation, i-electrode enhle kakhulu yokukhipha i-lithium iyawa, kanye nokubola kwe-oxidative kwe-electrolyte (ukwenzeka kwemikhiqizo engeyona eyejwayelekile kanye nokukhiqizwa kwegesi) kuyashesha.Uma ibhethri selichithwe ngokweqile, i-foil yethusi ivamise ukuncibilika (ukuvimbela ukushumeka kwe-lithium, noma ukukhiqiza ngokuqondile ama-dendrite ethusi), okuholela ekulimazeni umthamo noma ukwehluleka kwebhethri.
Ucwaningo lwesu lokushaja lubonise ukuthi uma ivolthi yokushaja enqamukayo ingu-4V, ukwehlisa ngokufanelekile amandla kagesi anqamule ukushaja (isb., 3.95V) kungathuthukisa impilo yomjikelezo webhethri.Kuphinde kwaboniswa ukuthi ukushaja ibhethri ngokushesha ukuya ku-100% SOC kubola ngokushesha kunokushaja okusheshayo ukuya ku-80% SOC.Ngaphezu kwalokho, uLi et al.ithole ukuthi nakuba i-pulsing ingathuthukisa ukusebenza kahle kokushaja, ukumelana kwangaphakathi kwebhethri kuzokhuphuka kakhulu, futhi ukulahlekelwa kwezinto ezisebenzayo ze-electrode kubi kakhulu.
7.Izinga lokushisa
Umphumela wezinga lokushisa kumthamo weamabhethri e-lithium-ionnayo ibaluleke kakhulu.Uma isebenza emazingeni okushisa aphakeme isikhathi eside, kuba khona ukwanda kokusabela okuseceleni ngaphakathi kwebhethri (isb., ukubola kwe-electrolyte), okuholela ekulahlekelweni kwamandla okungenakulungiseka.Uma usebenza emazingeni okushisa aphansi isikhathi eside, ukuvinjelwa okuphelele kwebhethri kuyanda (i-electrolyte conductivity iyancipha, i-impedance ye-SEI iyanda, futhi izinga lokusabela kwe-electrochemical liyehla), futhi imvula ye-lithium evela ebhethri ijwayele ukwenzeka.
Lokhu okungenhla kuyisizathu esiyinhloko sokuwohloka komthamo webhethri ye-lithium-ion, ngesingeniso esingenhla ngikholelwa ukuthi unokuqonda izimbangela zokuwohloka komthamo webhethri ye-lithium-ion.
Isikhathi sokuthumela: Jul-24-2023