Ukhuseleko lwebhetri yeLithium

Iibhetri zeLithium zinezibonelelo zokuphatheka kunye nokutshaja ngokukhawuleza, kutheni ke iibhetri ze-lead-acid kunye nezinye iibhetri zesibini zisajikeleza kwimarike?
Ukongeza kwiingxaki zeendleko kunye neendawo ezahlukeneyo zesicelo, esinye isizathu sikhuseleko.
ILithium yeyona ntsimbi isebenzayo ehlabathini.Ngenxa yokuba iimpawu zayo zeekhemikhali zisebenza kakhulu, xa i-lithium metal ibonakaliswe emoyeni, iya kuba nefuthe elibukhali le-oxidation kunye ne-oksijini, ngoko ke iyakwazi ukuqhuma, ukutshisa kunye nezinye izinto.Ukongeza, ukusabela kwe-redox kuya kwenzeka ngaphakathi kwebhetri ye-lithium ngexesha lokutshaja kunye nokukhupha.Ukuqhuma kunye nokutshisa okuzenzekelayo kubangelwa ikakhulu kukuqokelela, ukusabalalisa kunye nokukhululwa kwebhetri ye-lithium emva kokufudumeza.Ngamafutshane, iibhetri ze-lithium ziya kuvelisa ubushushu obuninzi ngexesha lokutshaja kunye nokukhupha inkqubo, okuya kubangela ukunyuka kweqondo lokushisa kwangaphakathi kwebhetri kunye nokushisa okungalinganiyo phakathi kweebhetri zomntu ngamnye, ngaloo ndlela kubangele ukusebenza okungazinzanga kwebhetri.
Ukuziphatha okungakhuselekanga kwebhetri ye-lithium-ion ebalekayo (kubandakanya ukutshaja kwebhetri kunye nokukhupha ngaphezulu, ukuhlawuliswa ngokukhawuleza kunye nokukhutshwa, isiphaluka esifutshane, iimeko zokusetyenziswa kakubi komatshini, ukutshatyalaliswa kobushushu obuphezulu be-thermal, njl. ukonakalisa ngokuthe ngqo ifilimu ye-passive kwi-electrode embi kunye ne-electrode surface.
Kukho izizathu ezininzi zokubangela iingozi ze-thermal ezibalekayo kwiibhetri ze-lithium ion.Ngokweempawu zokuqalisa, inokwahlulwa ibe yi-mechanical abuse triggering, i-electrical abuse i-triggering and thermal abuse triggering.Ukuxhatshazwa koomatshini: kubhekisa kwi-acupuncture, extrusion kunye nefuthe lezinto ezinzima ezibangelwa kukungqubana kwesithuthi;Ukusetyenziswa kakubi kombane: ngokuqhelekileyo kubangelwa ulawulo olungafanelekanga lombane okanye ukusilela kwecandelo lombane, kubandakanywa isekethe emfutshane, i-overcharge kunye ne-overdischarge;Ukusetyenziswa kakubi kobushushu: okubangelwa kukufudumala okubangelwa kulawulo olungafanelekanga lobushushu.

Ezi ndlela zintathu zokuqalisa zinxulumene.Ukusetyenziswa kakubi komatshini ngokuqhelekileyo kuya kubangela ukuguqulwa okanye ukuphuka kwe-diaphragm yebhetri, okubangelwa ukudibanisa ngokuthe ngqo phakathi kweepali ezilungileyo kunye nezibi zebhetri kunye nesiphaluka esifutshane, okubangelwa ukusetyenziswa kakubi kombane;Nangona kunjalo, phantsi kwemeko yokusetyenziswa kakubi kombane, isizukulwana sobushushu esifana nobushushu beJoule buyanyuka, sibangela ukuba ubushushu bebhetri bunyuke, bukhule bube bubushushu bobushushu, buqhubele phambili ukuvelisa uhlobo lobushushu becala ngaphakathi kwebhetri, kwaye ekugqibeleni lukhokelela kwisehlo. Ubushushu bebhetri bubaleka.
Ibhetri ye-thermal runaway ibangelwa kukuba izinga lokuvelisa ukushisa kwebhetri liphezulu kakhulu kunomlinganiselo wokutshatyalaliswa kobushushu, kwaye ubushushu buqokelelwa kwisixa esikhulu kodwa bungachithwanga ngexesha.Enyanisweni, "i-runaway ye-thermal" yinkqubo yomjikelezo wempendulo yamandla: ukunyuka kweqondo lokushisa kuya kubangela ukuba inkqubo ibe shushu, kwaye iqondo lokushisa liya kunyuka emva kokuba inkqubo ishushu, eya kwenza inkqubo ibe shushu.
Inkqubo yokubaleka kwe-thermal: xa ibhetri yangaphakathi yokushisa iphakama, ifilimu ye-SEI phezu kwefilimu ye-SEI ibola phantsi kobushushu obuphezulu, i-ion ye-lithium efakwe kwi-graphite iya kusabela kunye ne-electrolyte kunye ne-binder, iqhube ngakumbi ukufudumala kwebhetri. ukuya kwi-150 ℃, kwaye intshukumo entsha enobundlobongela exothermic iyakwenzeka kobu bushushu.Xa ubushushu bebhetri bufikelela ngaphezu kwe-200 ℃, izinto ze-cathode ziyabola, zikhupha ubushushu kunye negesi eninzi, kwaye ibhetri iqala ukukhupha kwaye iqhube ngokuqhubekayo.I-anode efakwe kwi-lithium yaqala ukusabela nge-electrolyte kwi-250-350 ℃.Izinto ezihlawuliswayo ze-cathode ziqala ukufumana impendulo yobundlobongela, kwaye i-electrolyte ifumana impendulo ye-oxidation enobudlova, ikhulula ubushushu obukhulu, ivelise ubushushu obuphezulu kunye nexabiso elikhulu legesi, ebangela ukutsha kunye nokuqhuma kwebhetri.
Ingxaki ye-lithium dendrite precipitation ngexesha lokugqithisa: Emva kokuba ibhetri ye-lithium cobalate ihlawuliswe ngokupheleleyo, inani elikhulu le-lithium ion lihlala kwi-electrode efanelekileyo.Oko kukuthi, i-cathode ayikwazi ukubamba i-lithium ion ezininzi ezifakwe kwi-cathode, kodwa kwimeko egqithisiweyo, i-lithium ion engaphezulu kwi-cathode iya kuqubha kwi-cathode.Ngenxa yokuba ayinakuqulathwa ngokupheleleyo, i-lithium yensimbi iya kwenza kwi-cathode.Ekubeni le lithium yentsimbi i-crystal dendritic, ibizwa ngokuba yi-dendrite.Ukuba i-dendrite inde kakhulu, kulula ukugqobhoza i-diaphragm, ebangela isiphaluka esifutshane sangaphakathi.Njengoko inxalenye ephambili ye-electrolyte yi-carbonate, indawo yayo yokutshisa kunye neqondo lokubilisa liphantsi, ngoko liya kutshisa okanye liqhume kwiqondo lokushisa eliphezulu.

Ukuba ibhetri ye-lithium ye-polymer, i-electrolyte i-colloidal, ejongene nokutsha okunobundlobongela.Ukuze kulungiswe le ngxaki, izazinzulu zizama ukubuyisela izinto ezikhuselekileyo ze-cathode.Izinto eziphathekayo zebhetri ye-lithium manganenate zineenzuzo ezithile.Inokuqinisekisa ukuba i-ion ye-lithium ye-electrode efanelekileyo inokufakwa ngokupheleleyo kwi-carbon emngxunyeni we-electrode engafanelekanga phantsi kolawulo olupheleleyo, endaweni yokuba ibe neentsalela ezithile kwi-electrode efanelekileyo njenge-lithium cobalate, ethi kwinqanaba elithile liphephe ukuveliswa iidendrites.Isakhiwo esizinzile se-lithium manganenate senza ukusebenza kwayo kwe-oxidation kuphantsi kakhulu kune-lithium cobalate.Nangona kukho i-short circuit yangaphandle (kunokuba i-short circuit yangaphakathi), inokuphepha ngokusisiseko ukutsha kunye nokuqhuma okubangelwa yi-lithium metal precipitation.I-lithium iron phosphate inozinzo oluphezulu lwe-thermal kunye nomthamo ophantsi we-oxidation ye-electrolyte, ngoko inokhuseleko oluphezulu.
Ukunciphisa ukuguga kwebhetri ye-lithium ion kubonakaliswa ngokunciphisa umthamo kunye nokunyuka kwangaphakathi kokuchasana, kwaye indlela yayo yokunciphisa ukuguga yangaphakathi iquka ukulahlekelwa kwezinto ezilungileyo kunye ezimbi ezisebenzayo kunye nokulahlekelwa kwee-ion ze-lithium ezikhoyo.Xa izinto ze-cathode zikhulile kwaye zibolile, kwaye amandla e-cathode ayanelanga, umngcipheko we-lithium evolution ukusuka kwi-cathode inokwenzeka ukuba yenzeke.Ngaphantsi kwemeko yokukhutshwa okungaphezulu, amandla e-cathode kwi-lithium aya kunyuka aye ngaphezulu kwe-3V, ephezulu kunokutshatyalaliswa kobhedu, okubangela ukuchithwa komqokeleli wobhedu.Iiyoni zethusi ezichithiweyo ziya kudlula kwi-cathode surface kwaye zenze ii-dendrites zethusi.I-dendrites ye-Copper iya kudlula kwi-diaphragm, ibangele isiphaluka esifutshane sangaphakathi, esichaphazela kakhulu ukusebenza kokhuseleko lwebhetri.
Ukongeza, ukuxhathisa i-overcharge yeebhetri zokuguga kuya kuncipha ukuya kumlinganiselo othile, ngokukodwa ngenxa yokwanda kokuchasana kwangaphakathi kunye nokuncipha kwezinto ezisebenzayo kunye nezingalunganga, okukhokelela ekwandeni kobushushu bejoule ngexesha lenkqubo yokutshaja ngaphezulu kweebhetri.Phantsi kokutshaja okugqithisileyo, iintshukumo ezisecaleni zinokuvuswa, kubangele ukubaleka kweebhetri.Ngokumalunga nokuzinza kwe-thermal, i-lithium evolution evela kwi-cathode iya kukhokelela ekunciphiseni okubukhali kwi-thermal stability yebhetri.
Ngelizwi, ukusebenza kokhuseleko kwebhetri endala kuya kuncitshiswa kakhulu, okuya kubeka emngciphekweni ukhuseleko lwebhetri.Esona sisombululo sixhaphakileyo kukuxhobisa inkqubo yokugcina amandla ebhetri ngenkqubo yokulawula ibhetri (BMS).Umzekelo, iibhetri ze-8000 18650 ezisetyenziswe kwi-Tesla Model S inokuqonda ukujonga ixesha lokwenyani kwiiparamitha ezahlukeneyo zebhetri, ivavanye imeko yokusetyenziswa kwebhetri, kwaye iqhube ukuxilongwa kwe-intanethi kunye nesilumkiso kwangoko ngenkqubo yolawulo lwebhetri.Ngexesha elifanayo, inokwenza kwakhona ukukhutshwa kunye nokulawulwa kwangaphambili kwentlawulo, ukulawulwa kwebhalansi yebhetri kunye nokulawulwa kwe-thermal.