Kusukela amabhethri e-lithium-ion angena emakethe, asetshenziswe kabanzi ngenxa yezinzuzo zawo zokuphila isikhathi eside, umthamo othize omkhulu, futhi akukho mphumela wenkumbulo. Ukusetshenziswa kwezinga lokushisa eliphansi lamabhethri e-lithium-ion kunezinkinga ezifana nomthamo ophansi, ukuncipha okukhulu, ukusebenza kahle kwezinga lomjikelezo, ukufakwa kwe-lithium okusobala, kanye nokukhishwa kwe-lithium okungalingani. Kodwa-ke, ngokwanda okuqhubekayo kwezinkambu zohlelo lokusebenza, izithiyo ezibangelwa ukusebenza okuphansi kwezinga lokushisa eliphansi lamabhethri e-lithium-ion ziya ngokuya ziba sobala.

Ngokwemibiko, amandla okukhipha amabhethri e-lithium-ion ku–20°C angaba ngu-31.5% kuphela walokho ezingeni lokushisa elivamile. Izinga lokushisa elisebenzayo lamabhethri e-lithium-ion endabuko liphakathi kuka -20 kanye +55 °C. Kodwa-ke, emikhakheni ye-aerospace, imboni yezempi, izimoto zikagesi, njll., ibhethri iyadingeka ukuthi isebenze ngokujwayelekile ku -40°C. Ngakho-ke, kubaluleke kakhulu ukuthuthukisa izakhiwo zokushisa eziphansi zamabhethri e-Li-ion.

Izinto Ezikhawulela Izinga Lokushisa Eliphansi Ukusebenza Kwamabhethri e-Li-ion

Endaweni yokushisa ephansi, i-viscosity ye-electrolyte iyanda futhi iqina kancane, okuholela ekwehleni kokusebenza kwamabhethri e-lithium-ion.

Ukuhambisana phakathi kwe-electrolyte kanye ne-electrode engalungile kanye nesihlukanisi kuba mpofu endaweni yokushisa ephansi.

I-electrode eyinegethivu yebhethri ye-lithium-ion inemvula ye-lithium engathi sína ngaphansi kwemvelo enezinga lokushisa eliphansi, futhi i-lithium yensimbi eginqikayo isabela ne-electrolyte, futhi ukubekwa komkhiqizo wayo kuholela ekwandeni kogqinsi lwesixhumi esibonakalayo esiqinile-electrolyte (SEI).

Ezimweni zokushisa eziphansi, uhlelo lokusabalalisa lwamabhethri e-Li-ion ezintweni ezisebenzayo luyancipha, futhi ukumelana nokudlulisa ukushaja (Rct) kukhula kakhulu.

Ingxoxo Ngezici Ezithinta Ukusebenza Kwezinga Lokushisa Eliphansi Lamabhethri e-Li-ion

Umbono wochwepheshe 1: I-electrolyte inomthelela omkhulu ekusebenzeni okuphansi kwezinga lokushisa kwamabhethri e-lithium-ion, futhi ukwakheka kanye nezakhiwo ze-physicochemical ye-electrolyte kunomthelela obalulekile ekusebenzeni kwezinga lokushisa eliphansi kwebhethri. Izinkinga ezibhekene nomjikelezo webhethri ekushiseni okuphansi yilezi: i-viscosity ye-electrolyte izokhula, futhi ijubane le-ion conduction lizohamba kancane, okuholela ekuphambeni kwejubane lokufuduka kwe-electron yesifunda sangaphandle, ngakho-ke ibhethri ihlukaniswe kakhulu, futhi umthamo wokushaja nokukhishwa kwehle kakhulu. Ikakhulukazi uma ishaja ngezinga lokushisa eliphansi, i-lithium ion yenza kalula i-lithium dendrites ebusweni be-electrode engalungile, okuholela ekungasebenzini kwebhethri.

Ukusebenza okuphansi kwezinga lokushisa kwe-electrolyte kuhlobene eduze nobukhulu be-conductivity ye-electrolyte ngokwayo. I-electrolyte ene-conductivity ephezulu idlulisela ama-ion ngokushesha futhi ingasebenzisa umthamo owengeziwe ekushiseni okuphansi. Lapho usawoti we-lithium uhlukaniswa kakhulu ku-electrolyte, inani lokufuduka likhuphuka futhi likhuphuka izinga lokuhamba. Ukuphakama kokuhamba kukagesi, izinga lokuqhuba kwe-ion liyashesha, i-polarization iyancipha, nokusebenza okungcono kwebhethri ezingeni lokushisa eliphansi. Ngakho-ke, ukuhanjiswa kukagesi okuphezulu kuyisimo esidingekayo ukuze kuzuzwe ukusebenza kahle kwezinga lokushisa eliphansi lamabhethri e-lithium-ion.

I-conductivity ye-electrolyte ihlobene nokubunjwa kwe-electrolyte, futhi ukunciphisa i-viscosity ye-solvent kungenye yezindlela zokuthuthukisa ukuqhutshwa kwe-electrolyte. I-fluidity enhle ye-solvent ekushiseni okuphansi yisiqinisekiso sokuthutha kwe-ion, futhi ifilimu eqinile ye-electrolyte eyakhiwe yi-electrolyte ku-electrode engalungile ekushiseni okuphansi futhi iyisihluthulelo sokuthinta ukuqhutshwa kwe-lithium ion, futhi i-RSEI iyisivikelo esiyinhloko. amabhethri e-lithium ion ezindaweni eziphansi zokushisa.

Uchwepheshe 2: Isici esiyinhloko esikhawulela ukusebenza kwezinga lokushisa eliphansi lamabhethri e-lithium-ion ukwenyuka ngokucijile kokumelana nokusabalalisa kwe-Li+ emazingeni okushisa aphansi, hhayi ifilimu ye-SEI.

Izici zokushisa eziphansi zezinto ze-cathode zamabhethri e-lithium ion

1. Izici zokushisa eziphansi ze-layer cathode materials

Isakhiwo esinezingqimba asinakho kuphela ukusebenza kwezinga elingenakuqhathaniswa leziteshi zokusabalalisa i-lithium ion ezinohlangothi olulodwa, kodwa futhi sinokuzinza kwesakhiwo seziteshi ezintathu-ntathu. Yimpahla yokuqala ye-cathode yokuhweba yamabhethri e-lithium ion. Izinto eziwumelayo yi-LiCoO2, Li(Co1-xNix)O2 kanye ne-Li(Ni, Co, Mn)O2 njalonjalo.

U-Xie Xiaohua et al. ithathe i-LiCoO2/MCMB njengento yocwaningo futhi yahlola izici zayo zokushaja okunezinga lokushisa eliphansi.

Imiphumela ibonisa ukuthi ngokuncipha kwezinga lokushisa, isiteji sokukhipha sehla kusuka ku-3.762V (0 ° C) kuya ku-3.207V (-30 ° C); umthamo webhethri usuwonke nawo wehla kakhulu ukusuka ku-78.98mA·h (0°C) ukuya ku-68.55mA·h (–30°C).

2. Izici zokushisa eziphansi ze-spinel-structured cathode materials

Isakhiwo se-spinel i-LiMn2O4 cathode material inezinzuzo zezindleko eziphansi futhi ezingenabo ubuthi ngoba ayiqukethe i-Co element.

Kodwa-ke, ukuhlukahluka kwe-valence kwe-Mn nomthelela we-Jahn-Teller we-Mn3+ kuholela ekuntengantengeni kwesakhiwo kanye nokungabuyiseleki kahle emuva kwale ngxenye.

U-Peng Zhengshun et al. wabonisa ukuthi izindlela ezahlukene zokulungiselela zinethonya elikhulu ekusebenzeni kwe-electrochemical of LiMn2O4 cathode materials. Ukuthatha i-Rct njengesibonelo: i-Rct ye-LiMn2O4 ehlanganiswe ngokushisa okuphezulu kwendlela yesigaba esiqinile iphakeme kakhulu kunendlela ye-sol-gel, futhi lesi simo asithintwa yi-lithium ion. I-coefficient yokusabalalisa nayo iyaboniswa. Isizathu siwukuthi izindlela ezihlukene zokuhlanganisa zinethonya elikhulu ekukhanyeni kwekristalu kanye ne-morphology yemikhiqizo.

3. Izici zokushisa eziphansi zezinto ze-cathode zesistimu ye-phosphate

Ngenxa yokuqina nokuphepha kwevolumu yayo okuhle kakhulu, i-LiFePO4, kanye nezinto ezisetshenziswayo ze-ternary, isibe indikimba eyinhloko yezinto zamanje zebhethri ze-cathode. Ukungasebenzi kahle kwezinga lokushisa eliphansi kwe-lithium iron phosphate ikakhulukazi ngenxa yokuthi impahla yayo ngokwayo iyisivikeli, esine-conductivity ephansi ye-elekthronikhi, i-lithium ion diffusivity empofu, nokungahambi kahle kahle ekushiseni okuphansi, okwandisa ukumelana kwangaphakathi kwebhethri, okuthinteka kakhulu i-polarization, kanye nokushajwa kwebhethri nokuphuma kuvinjelwe. Ngakho-ke, izinga lokushisa eliphansi Ukusebenza alilungile.

Lapho ufunda ukuziphatha kwe-charge-dicharge ye-LiFePO4 ezingeni lokushisa eliphansi, u-Gu Yijie et al. ithole ukuthi ukusebenza kahle kwayo kwe-coulombic kwehle kusuka ku-100% ku-55°C kuya ku-96% ku-0°C no-64% ku–20°C, ngokulandelana; i-voltage yokukhipha yehlile isuka ku-3.11V ku-55°C. Yehla uye ku-2.62V ku-–20°C.

Xing et al. i-LiFePO4 eguquliwe nge-nanocarbon futhi yathola ukuthi ngemva kokwengeza i-nanocarbon i-agent conductive, ukusebenza kwe-electrochemical ye-LiFePO4 kwakungazwela kakhulu ekushiseni, futhi ukusebenza okuphansi kwezinga lokushisa kwathuthukiswa; i-voltage yokukhipha ye-LiFePO4 eguquliwe ikhuphuke isuka ku-3.40 ku-25 ° CV yehla yaya ku-3.09V ku–25 ° C, ukwehla kwe-9.12% kuphela; kanye nokusebenza kahle kwamaseli ku–25°C kungu-57.3%, okungaphezulu kuka-53.4% ​​ngaphandle kwe-nano-carbon conductive agent.

Muva nje, i-LiMnPO4 isihehe abantu abaningi. Ucwaningo luthole ukuthi i-LiMnPO4 inezinzuzo zamandla aphezulu (4.1V), akukho ukungcola, intengo ephansi, nomthamo omkhulu othize (170mAh/g). Nokho, ngenxa ye-ionic ephansi ye-LiMnPO4 kune-LiFePO4, i-Fe ivamise ukusetshenziselwa ukufaka esikhundleni sika-Mn kancane ukuze yenze isixazululo esiqinile se-LiMn0.8Fe0.2PO4 ekusebenzeni.

Izici zokushisa eziphansi zezinto ze-anode zamabhethri e-lithium ion

Uma kuqhathaniswa nezinto ezibonakalayo ze-electrode, ukuwohloka kwezinga lokushisa eliphansi kwempahla ye-electrode eyi-negative yebhethri ye-lithium ion kubi kakhulu, ikakhulukazi ngenxa yezizathu ezintathu ezilandelayo:

Lapho ishaja futhi ikhipha ekushiseni okuphansi kanye nezinga eliphezulu, ibhethri lihlukaniswa ngokujulile, futhi inani elikhulu le-lithium yensimbi lifakwa ebusweni be-electrode engalungile, futhi umkhiqizo wokusabela we-lithium yensimbi ne-electrolyte ngokuvamile awunayo conductivity;

Kusukela ekubukeni kwe-thermodynamic, i-electrolyte iqukethe inani elikhulu lamaqembu e-polar afana ne-CO ne-CN, engasabela ngezinto ezingezinhle ze-electrode, futhi ifilimu ye-SEI eyakhiwe isengozini kakhulu ekushiseni okuphansi;

I-carbon negative electrode inzima ukuhlanganisa i-lithium ekushiseni okuphansi, futhi kukhona ukushaja nokukhipha i-asymmetric.

isithombe

Ucwaningo nge-Low Temperature Electrolyte

I-electrolyte idlala indima yokuthutha i-Li+ ngamabhethri e-lithium-ion, futhi ukusebenza kwayo kwe-ionic kanye nezakhiwo zefilimu ye-SEI kunomthelela obalulekile ekusebenzeni kwezinga lokushisa eliphansi kwebhethri. Kunezinkomba ezintathu eziyinhloko zokwahlulela okuhle nokubi kwe-electrolyte esezingeni eliphansi: conductivity ionic, iwindi le-electrochemical kanye nokusebenza kabusha kwe-electrode. Izinga lalezi zinkomba ezintathu lincike kakhulu ezintweni ezihlanganisayo: i-solvent, i-electrolyte (usawoti we-lithium), nezithasiselo. Ngakho-ke, ucwaningo mayelana nokusebenza kwezinga lokushisa eliphansi kwengxenye ngayinye ye-electrolyte lubaluleke kakhulu ekuqondeni nasekuthuthukiseni ukusebenza kwezinga lokushisa eliphansi kwebhethri.

Uma kuqhathaniswa ne-chain carbonates, izici zokushisa eziphansi zama-electrolyte asekelwe ku-EC, ama-cyclic carbonates anesakhiwo esihlangene, amandla amakhulu abambayo, nendawo ephakeme yokuncibilika kanye ne-viscosity. Kodwa-ke, i-polarity enkulu elethwa yisakhiwo sendandatho yenza ngokuvamile ibe ne-dielectric constant constant. Ukungaguquguquki okukhulu kwe-dielectric, ukuhanjiswa kwe-ionic okuphezulu, kanye nezakhiwo ezinhle kakhulu zokwakha ifilimu zezincibilikisi ze-EC kuvimbela ngempumelelo ukufakwa kanyekanye kwama-athomu, okuwenza abaluleke kakhulu. Ngakho-ke, iningi lezinhlelo ze-electrolyte ezisezingeni eliphansi ezivame ukusetshenziswa zisekelwe ku-EC, bese zixutshwa i-solvent ye-molecule encane enephuzu eliphansi lokuncibilika.

Usawoti we-lithium uyingxenye ebalulekile ye-electrolyte. Usawoti we-lithium ku-electrolyte awukwazi nje ukuthuthukisa i-ionic conductivity yesisombululo, kodwa futhi unciphise ibanga lokusabalalisa lika-Li+ esixazululweni. Ngokuvamile, ukugcwala okukhulu kwe-Li+ esixazululweni, kukhulu ukuqhutshwa kwe-ionic. Kodwa-ke, ukugcwala kwama-ion e-lithium ku-electrolyte akuhlobene ngokuqondile nokugcwala kosawoti we-lithium, kodwa ku-parabolic. Lokhu kungenxa yokuthi ukugxila kwe-lithium ion ku-solvent kuncike emandleni okuhlukanisa kanye nokuhlangana kwama-lithium usawoti ku-solvent.

Ucwaningo nge-Low Temperature Electrolyte

Ngokungeziwe ekwakhekeni kwebhethri ngokwayo, izici zenqubo ekusebenzeni kwangempela nazo zizoba nomthelela omkhulu ekusebenzeni kwebhethri.
(1) Inqubo yokulungiselela. Yaqub et al. ifunde umthelela womthwalo we-electrode nokujiya kwe-coating ekusebenzeni kwezinga lokushisa eliphansi lamabhethri e-LiNi0.6Co0.2Mn0.2O2/Graphite futhi yathola ukuthi mayelana nokugcinwa komthamo, lapho umthamo we-electrode ube mncane kanye nokuncipha kwesendlalelo sokumboza, kuba ngcono ukuncipha. ukusebenza kwezinga lokushisa. .

(2) Isimo sokukhokhiswa nokukhishwa. Petzl et al. ifunde umthelela wesimo sokushajwa kwebhethri elisezingeni eliphansi empilweni yomjikelezo webhethri, yaphinde yathola ukuthi uma ukujula kokukhipha kukukhulu, kuzodala ukulahleka kwamandla okukhulu futhi kunciphise impilo yomjikelezo.

(3) Ezinye izici. Indawo engaphezulu, usayizi wembotshana, ukuminyana kwe-electrode, ukumanzisa kwe-electrode ne-electrolyte, nesihlukanisi, njll., konke kuthinta ukusebenza kwezinga lokushisa eliphansi lamabhethri e-lithium-ion. Ngaphezu kwalokho, ithonya lezinto ezibonakalayo kanye nezinqubo zokukhubazeka ekusebenzeni okuphansi kwezinga lokushisa kwebhethri akukwazi ukushaywa indiva.

Fingqa

Ukuze uqinisekise ukusebenza okuphansi kwezinga lokushisa kwamabhethri e-lithium-ion, amaphuzu alandelayo adinga ukwenziwa:

(1) Yakha ifilimu ye-SEI ezacile neminyene;

(2) Qinisekisa ukuthi i-Li+ ine-coefficient enkulu yokusabalalisa ezintweni ezisebenzayo;

(3) I-electrolyte ine-ionic conductivity ephezulu ekushiseni okuphansi.

Ngaphezu kwalokho, ucwaningo lungathola enye indlela yokubheka olunye uhlobo lwebhethri ye-lithium-ion-all-solid-state lithium-ion battery. Uma kuqhathaniswa namabhethri e-lithium-ion avamile, amabhethri e-lithium-ion embuso aqinile, ikakhulukazi amabhethri e-lithium-ion efilim eqinile, alindeleke ukuthi ayixazulule ngokuphelele inkinga yokubola kwamandla kanye nokuphepha komjikelezo lapho amabhethri esetshenziswa. amazinga okushisa aphansi. c