Ezimweni zokushisa eziphansi, ukusebenza kwebhethri ye-lithium-ion akulungile.Lapho amabhethri e-lithium-ion asetshenziswa ngokuvamile esebenza ku--10 ° C, umthamo wawo omkhulu wokushaja nokukhishwa kwamandla kanye ne-terminal voltage izoncishiswa kakhulu uma kuqhathaniswa nezinga lokushisa elivamile [6], lapho izinga lokushisa lokukhipha lehla liye ku-20 ° C, amandla atholakalayo ngisho nokwehliswa ku-1/3 ekamelweni lokushisa 25 ° C, lapho izinga lokushisa lokukhipha liphansi, amanye amabhethri e-lithium awakwazi ngisho nokushaja nokukhipha imisebenzi, engena esimweni "sebhethri efile".
1, Izici zamabhethri e-lithium-ion emazingeni okushisa aphansi
(1) I-Macroscopic
Izinguquko zesici sebhethri ye-lithium-ion ekushiseni okuphansi zimi kanje: ngokuncipha okuqhubekayo kwezinga lokushisa, ukumelana ne-ohmic kanye nokwenyuka kokumelana ne-polarization ngamadigri ahlukene;I-voltage yokukhipha yebhethri ye-lithium-ion iphansi kunezinga lokushisa elivamile.Lapho ishaja futhi ishajwa ngezinga lokushisa eliphansi, i-voltage yayo yokusebenza ikhuphuka noma yehla ngokushesha kunaleyo ezingeni lokushisa elivamile, okuholela ekwehleni okuphawulekayo komthamo wayo omkhulu osebenzisekayo namandla.
(2) Ngokwe-microscope
Izinguquko zokusebenza kwamabhethri e-lithium-ion emazingeni okushisa aphansi ikakhulukazi ngenxa yethonya lezici ezibalulekile ezilandelayo.Lapho izinga lokushisa lendawo lingaphansi kuka -20 ℃, i-electrolyte ewuketshezi iyaqina, i-viscosity yayo ikhula kakhulu, futhi ukuqhutshwa kwe-ionic yayo kuncipha.Ukusabalalisa kwe-ion ye-lithium ezintweni ezinhle nezingezinhle ze-electrode kuhamba kancane;I-Lithium ion inzima ukuyichitha, futhi ukudluliswa kwayo kufilimu ye-SEI kuhamba kancane, futhi i-impedance yokudlulisa icala iyanda.Inkinga ye-lithium dendrite igqame kakhulu ekushiseni okuphansi.
2, Ukuxazulula izinga lokushisa eliphansi ukusebenza kwamabhethri e-lithium-ion
Dala uhlelo olusha lwe-electrolytic liquid ukuhlangabezana nemvelo ephansi yokushisa;Thuthukisa ukwakheka kwe-electrode enhle nengalungile ukusheshisa isivinini sokudlulisela futhi unciphise ibanga lokudlulisela;Lawula isixhumi esibonakalayo esiqinile nesibi se-electrolyte ukuze unciphise i-impedance.
(1) izithasiselo ze-electrolyte
Ngokuvamile, ukusetshenziswa kwezithasiselo ezisebenzayo kungenye yezindlela eziphumelela kakhulu nezongayo zokuthuthukisa ukusebenza okuphansi kwezinga lokushisa kwebhethri nokusiza ukwakha ifilimu ye-SEI ekahle.Njengamanje, izinhlobo eziyinhloko zezithasiselo ziyizithasiselo ezisekelwe ku-isocyanate, izithasiselo ezisekelwe ku-sulfur, izithasiselo ze-ionic liquid kanye nezithako zikasawoti ze-lithium ezingaphili.
Isibonelo, izithasiselo ezisekelwe ku-dimethyl sulfite (DMS) ezisekelwe ku-sulfur, ezinomsebenzi ofanele wokunciphisa, futhi ngenxa yokuthi imikhiqizo yayo yokunciphisa kanye ne-lithium ion ebophayo ibuthakathaka kune-vinyl sulfate (DTD), ukunciphisa ukusetshenziswa kwezithasiselo eziphilayo kuzokwandisa i-impedance, ukwakha ezinze kakhudlwana futhi kangcono ionic conductivity of the negative electrode interface ifilimu.Ama-sulfite esters amelwe i-dimethyl sulfite (DMS) anezinga lokushisa eliphakeme le-dielectric elingaguquki kanye nebanga lokushisa elibanzi lokusebenza.
(2) I-solvent ye-electrolyte
I-electrolyte yebhethri ye-lithium-ion yendabuko iwukuncibilikisa i-1 mol ye-lithium hexafluorophosphate (LiPF6) ibe yi-solvent exubile, njenge-EC, PC, VC, DMC, methyl ethyl carbonate (EMC) noma i-diethyl carbonate (DEC), lapho ukwakheka kwe i-solvent, i-melting point, i-dielectric constant, i-viscosity kanye nokuhambisana nosawoti we-lithium kuzothinta kakhulu izinga lokushisa lokusebenza kwebhethri.Njengamanje, i-electrolyte yezentengiselwano kulula ukuyiqinisa uma isetshenziswa endaweni yokushisa ephansi engu -20 ℃ nangaphansi, i-dielectric engaguquki yenza kube nzima ukuhlukanisa usawoti we-lithium, futhi i-viscosity iphakeme kakhulu ukwenza ibhethri ukumelana kwangaphakathi futhi iphansi. isiteji se-voltage.Amabhethri e-lithium-ion angaba nokusebenza okungcono kwezinga lokushisa eliphansi ngokuthuthukisa isilinganiso esikhona se-solvent, njengokwenza ngcono ukwakheka kwe-electrolyte (EC:PC:EMC=1:2:7) ukuze i-TiO2(B)/graphene electrode negative ibe no-A. umthamo ~240 mA h g-1 at -20℃ kanye 0.1 A g-1 ukuminyana kwamanje.Noma thuthukisa izincibilikisi ze-electrolyte ezintsha.Ukusebenza kabi kwamabhethri e-lithium-ion emazingeni okushisa aphansi ikakhulukazi kuhlobene nokuqedwa kancane kwe-Li+ phakathi nenqubo yokushumeka kwe-Li+ ezintweni ze-electrode.Izinto ezinamandla okubopha aphansi phakathi kwe-Li+ nama-athomu ezincibilikayo, njenge-1, 3-dioxopentylene (DIOX), zingakhethwa, futhi i-nanoscale lithium titanate isetshenziswa njengento ye-electrode ukuhlanganisa ukuhlolwa kwebhethri ukunxephezela i-coefficient encishisiwe yokusabalalisa izinto ze-electrode emazingeni okushisa aphansi kakhulu, ukuze kuzuzwe ukusebenza okungcono kwezinga lokushisa eliphansi.
(3) usawoti we-lithium
Njengamanje, i-ion yezentengiselwano ye-LiPF6 ine-conductivity ephezulu, izidingo zomswakama ophezulu emvelweni, ukunganzinzi kahle kokushisa, namagesi amabi afana ne-HF ekuphenduleni kwamanzi kulula ukubangela izingozi zokuphepha.Ifilimu ye-electrolyte eqinile ekhiqizwe i-lithium difluoroxalate borate (LiODFB) izinzile ngokwanele futhi inokusebenza okungcono kwezinga lokushisa eliphansi kanye nokusebenza kwezinga eliphezulu.Lokhu kungenxa yokuthi i-LiODFB inezinzuzo zako kokubili i-lithium dioxalate borate (LiBOB) ne-LiBF4.
3. Isifinyezo
Ukusebenza okuphansi kwezinga lokushisa kwamabhethri e-lithium-ion kuzothinteka izici eziningi ezifana nezinto ze-electrode nama-electrolyte.Ukuthuthukiswa okuphelele okuvela emibonweni eminingi efana nezinto ze-electrode kanye ne-electrolyte kungakhuthaza ukusetshenziswa nokuthuthukiswa kwamabhethri e-lithium-ion, futhi ithemba lokusetshenziswa kwamabhethri e-lithium lihle, kodwa ubuchwepheshe budinga ukuthuthukiswa futhi bupheleliswe ocwaningweni olwengeziwe.
Isikhathi sokuthumela: Jul-27-2023