Batura lithium suna da fa'idar ɗaukar nauyi da sauri, don haka me yasa batirin gubar-acid da sauran batura na biyu ke yawo a kasuwa?
Baya ga matsalolin farashi da filayen aikace-aikacen daban-daban, wani dalili kuma shine tsaro.
Lithium shine karfe mafi aiki a duniya.Saboda halayensa suna da ƙarfi sosai, idan ƙarfen lithium ya fallasa a iska, zai sami mummunan yanayin oxygenation tare da iskar oxygen, don haka yana saurin fashewa, konewa da sauran abubuwan mamaki.Bugu da kari, redox dauki kuma zai faru a cikin baturin lithium yayin caji da fitarwa.Fashewa da konewa ba zato ba tsammani suna faruwa ne ta hanyar tarawa, yaduwa da sakin batirin lithium bayan dumama.A takaice dai, batirin lithium zai haifar da zafi mai yawa a yayin aikin caji da fitar da wuta, wanda hakan zai haifar da hauhawar zafin cikin batirin da rashin daidaito tsakanin batir guda daya, wanda hakan zai haifar da rashin kwanciyar hankali na batir.
Halayyan rashin tsaro na batir lithium-ion mai saurin gudu (ciki har da cajin baturi da wuce gona da iri, saurin caji da fitarwa, gajeriyar kewayawa, yanayin cin zarafi na inji, tsananin zafin zafin jiki, da sauransu) na iya haifar da halayen haɗari a cikin baturin da haifar da zafi, kai tsaye lalata da m fim a kan korau electrode da tabbatacce lantarki surface.
Akwai dalilai da yawa don haifar da hatsarori masu gudu na zafi na batirin lithium ion.Dangane da halayen haɓakawa, ana iya raba shi zuwa haifar da zagi na injiniya, haifar da lalata wutar lantarki da haifar da zagi na thermal.Cin zarafi na injiniya: yana nufin acupuncture, extrusion da tasirin abu mai nauyi wanda ya haifar da karon abin hawa;Zagin wutar lantarki: gabaɗaya ana haifar da shi ta hanyar sarrafa wutar lantarki mara kyau ko gazawar bangaren lantarki, gami da gajeriyar kewayawa, caji da wuce gona da iri;Cin zarafi: sakamakon zafi mai zafi wanda rashin kula da yanayin zafi ya haifar.
Wadannan hanyoyi guda uku masu tayar da hankali suna da alaƙa.Cin zarafi na injina gabaɗaya zai haifar da lalacewa ko fashewar diaphragm na baturi, yana haifar da tuntuɓar kai tsaye tsakanin ingantattun sanduna mara kyau da mara kyau na baturin da gajeriyar kewayawa, yana haifar da cin zarafin lantarki;Sai dai kuma a karkashin yanayin da ake amfani da wutar lantarki, samar da zafi kamar Joule zafi yana karuwa, wanda hakan ke sa zafin batirin ya hauhawa, wanda ke tasowa ya zama cin zarafi, yana kara haifar da martanin bangaren da ke haifar da nau'in zafi a cikin batirin, kuma a karshe ya haifar da faruwar lamarin. na guduwar zafin baturi.
Guduwar yanayin zafi na baturi yana faruwa ne sakamakon yadda yawan zafin batirin da ake samu ya fi yawan zafin da ake kashewa, kuma zafi yana taruwa da yawa amma ba ya watse cikin lokaci.Ainihin, "Runaway thermal" shine tsarin sake zagayowar makamashi mai kyau: yanayin zafi zai haifar da tsarin ya zama zafi, kuma zafin jiki zai tashi bayan tsarin ya yi zafi, wanda hakan zai sa tsarin ya zama zafi.
Tsarin runaway thermal: lokacin da zafin jiki na cikin baturi ya tashi, fim ɗin SEI akan saman fim ɗin SEI ya lalace a ƙarƙashin babban zafin jiki, ion lithium da aka saka a cikin graphite zai amsa tare da electrolyte da mai ɗaure, yana ƙara matsawa zafin baturi sama. zuwa 150 ℃, kuma sabon tashin hankali exothermic dauki zai faru a wannan zafin jiki.Lokacin da zafin baturi ya kai sama da 200 ℃, kayan cathode sun lalace, suna sakin babban adadin zafi da iskar gas, kuma baturin yana farawa kuma yana ci gaba da zafi.Lithium da aka saka anode ya fara amsawa tare da electrolyte a 250-350 ℃.Kayan cathode da aka caje ya fara fuskantar tashin hankali bazuwar halayen, kuma electrolyte yana fuskantar tashin hankali mai ƙarfi, yana sakin zafi mai yawa, yana haifar da babban zafin jiki da adadin iskar gas, yana haifar da konewa da fashewar baturi.
Matsalar lithium dendrite hazo yayin da ake caji: Bayan da aka cika cajin baturin lithium cobalate, adadi mai yawa na ion lithium ya kasance a cikin ingantaccen lantarki.Wato, cathode ba zai iya ɗaukar ƙarin ions lithium da aka haɗe zuwa cathode ba, amma a cikin jujjuyawar jujjuyawar lithium ions akan cathode har yanzu zai yi iyo zuwa cathode.Saboda ba za a iya cika su ba, ƙarfe na lithium zai kasance akan cathode.Tun da wannan ƙarfe lithium shine crystal dendritic, ana kiran shi dendrite.Idan dendrite ya yi tsayi da yawa, yana da sauƙi don huda diaphragm, yana haifar da gajeren kewaye na ciki.Kamar yadda babban abin da ke cikin electrolyte shine carbonate, wurin kunna shi da kuma tafasar sa ba su da yawa, don haka zai ƙone ko ma fashewa da zafi mai tsanani.
Idan baturin lithium na polymer ne, electrolyte colloidal ne, wanda ke da saurin konewa.Don magance wannan matsala, masana kimiyya suna ƙoƙarin maye gurbin kayan cathode mafi aminci.Kayan baturin manganate na lithium yana da wasu fa'idodi.Yana iya tabbatar da cewa lithium ion na tabbatacce electrode za a iya gaba daya saka a cikin carbon rami na korau electrode a karkashin cikakken cajin jihar, maimakon samun wasu saura a cikin m electrode kamar lithium cobalate, wanda zuwa wani mataki kauce wa tsara. dendrites.Tsayayyen tsarin lithium manganate yana sa aikin iskar oxygen ya yi ƙasa da na lithium cobalate.Ko da akwai gajeriyar da'ira ta waje (maimakon gajeriyar da'ira), yana iya guje wa konewa da fashewar hazo na ƙarfe na lithium.Lithium baƙin ƙarfe phosphate yana da mafi girma thermal kwanciyar hankali da ƙananan hadawan abu da iskar shaka iya aiki na electrolyte, don haka yana da babban aminci.
Rashin tsufa na baturin lithium ion yana bayyana ta hanyar rage ƙarfin aiki da haɓaka juriya na ciki, kuma tsarin tsufa na ciki ya haɗa da asarar kayan aiki masu kyau da mara kyau da asarar ions lithium.Lokacin da kayan cathode ya tsufa kuma ya lalace, kuma ƙarfin cathode bai isa ba, haɗarin haɓakar lithium daga cathode yana iya faruwa.Karkashin yanayin wuce gona da iri, yuwuwar cathode zuwa lithium zai tashi sama da 3V, wanda ya fi karfin narkar da tagulla, yana haifar da rushewar mai tara tagulla.Narkar da ions jan karfe za su yi hazo a saman cathode kuma su samar da dendrites na jan karfe.Copper dendrites zai wuce ta diaphragm, haifar da ciki gajeriyar da'ira, wanda da tsanani rinjayar da aminci aikin baturi.
Bugu da kari, yawan juriya na batura masu tsufa zai ragu zuwa wani matsayi, musamman saboda karuwar juriya na ciki da raguwar abubuwa masu kyau da mara kyau, wanda ke haifar da karuwar zafin joule yayin aikin cajin baturi.Ƙarƙashin ƙarancin caji, ana iya haifar da halayen gefe, wanda zai haifar da guduwar batura.Dangane da kwanciyar hankali na thermal, juyin halittar lithium daga cathode zai haifar da raguwa mai ƙarfi a cikin kwanciyar hankali na zafi na baturi.
A cikin kalma, aikin aminci na baturi mai tsufa zai ragu sosai, wanda zai yi haɗari da amincin baturin.Mafi na kowa mafita shine a ba da tsarin ajiyar makamashin baturi tare da tsarin sarrafa baturi (BMS).Misali, batura 8000 18650 da aka yi amfani da su a cikin Tesla Model S na iya gane ainihin lokacin sa ido kan sigogin jiki daban-daban na baturin, kimanta matsayin amfani da baturi, da gudanar da bincike na kan layi da faɗakarwa da wuri ta hanyar tsarin sarrafa baturi.A lokaci guda kuma, tana iya aiwatar da fitarwa da sarrafa caji kafin lokaci, sarrafa ma'aunin baturi da sarrafa zafi.
Lokacin aikawa: Dec-02-2022