Menene LiFePO4 a cikin batir lithium ??
Gabatarwa zuwa Kayayyakin Karfe na Lithium Iron Phosphate
Lithium iron phosphate (nau'in kwayoyin LiFePO₄, lithium iron phosphate, LFP, wanda kuma aka sani da lithium iron phosphate ko ferrous lithium phosphate) wani abu ne na cathode da ake amfani dashi a cikin batirin lithium{0}}. Siffofinsa shine cewa ba ya ƙunshi abubuwa masu daraja irin su cobalt ko nickel, farashin albarkatun ƙasa yana da ƙasa; da carbon, lithium, da iron suna da yawa a cikin ɓawon ƙasa, wanda zai iya biyan buƙatun kasuwa na fiye da tan miliyan ɗaya a kowace shekara. A matsayin kayan aikin cathode, lithium iron phosphate yana da matsakaicin ƙarfin aiki (3.2 V), ƙayyadaddun iya aiki (170 mA·h/g), ƙarfin fitarwa mai ƙarfi, ƙarfin caji mai sauri, da tsawon rayuwar zagayowar, tare da kyakkyawan kwanciyar hankali a cikin babban-zazzabi da yanayin zafi mai girma-.
Crystal phosphate na lithium baƙin ƙarfe nasa ne na nau'in tsarin olivine ɗaya. A cikin mineralogy, ana kiran shi triphylite, wanda aka samo daga kalmar Helenanci tushen tri da lylon. A cikin ma'adanai, launi na iya zama launin toka, ja-ja-jaja -launin toka, launin ruwan kasa, ko baki, yayin da ainihin samfuran baki ne ko launin toka{3}}baƙi. Wasu kayan ma'adinai na halitta sun ƙunshi lithium baƙin ƙarfe phosphate, amma darajar yana da ƙasa kuma baya kai matakin aikace-aikacen aiki. Lithium baƙin ƙarfe phosphate nasa ne da composite phosphate category, da kuma general sinadaran dabara kamata ya zama LiMPO₄, inda M iya zama kowane divalent karfe, ciki har da Fe, Co, Mn, Ti, da dai sauransu Domin na farko kamfanin da ya kasuwanci LiMPO₄ samar da lithium baƙin ƙarfe phosphate, mutane sun zama saba da zalunta lithium baƙin ƙarfe phosphate a matsayin kawai composite. Duk da haka, don mahadi masu tsarin olivine, lithium iron phosphate ba shine kawai wanda za'a iya amfani dashi azaman kayan cathode a cikin batir lithium{8}}. Dangane da ilimin yanzu, akwai kuma LiMnPO₄, LiMnFePO₄, LiVPO₄, LiCoPO₄, da sauran abubuwa da yawa.
Asalin kayan phosphate na lithium baƙin ƙarfe za a iya gano su tun 1996, lokacin da kamfanin sadarwa na Japan NTT ya fara gano cewa AMPO₄ (A ne alkali karfe, M ne Co ko Fe) tare da olivine tsarin, a hade da LiFeCoPO₄, za a iya amfani da matsayin lithium -ion baturi cathode. Daga baya, ƙungiyar bincike ta Goodenough a Cibiyar Fasaha ta Massachusetts da ke Amurka ta gano shi, yayin da ake nazarin mahadi na tsarin, cewa lithium iron phosphate abu yana da ikon juyar da lithium{3} ion (Li⁺) intercalation da deintercalation. A ranar 23 ga Afrilu, 1997, Jami'ar Texas a Austin ta ba da takardar izini mai suna "Kayan Kathode don batirin lithium na biyu na caji" (WO1997010541), wanda ke nuna farkon ikon mallakar ikon mallakar kayan lithium baƙin ƙarfe phosphate.
Bugawar olivine{0}tsararriyar phosphate (LiMPO₄) kayan katode na Amurka da Japan a lokaci guda ya ja hankali sosai, ya haifar da bincike mai zurfi, kuma cikin sauri ya haɓaka tsarin masana'antu. Idan aka kwatanta da na al'ada lithium -ion secondry baturi cathode kayan{3}}spinel{4} lithium manganese oxide (LiMn₂O₄) structured (LiMn₂O₄) da lebur {{5}structured lithium cobalt oxide (LiCoO₂)-LiMPO mai rahusa da albarkatun kasa. Musamman, aminci ya inganta sosai, yana haifar da sha'awar masu bincike da masana'antu.
Bisa ga sakamakon bincike a shekarun baya-bayan nan, sinadarin lithium iron phosphate yana da tsari mai kyau -crystallized olivine, kuma lithium{1} ion diffusion tashoshi ya bambanta da na kayan cathode na gargajiya. Kayan gargajiya na cathode suna da sifofi ko sifofi, suna barin ions lithium suyi sauri tsakanin yadudduka ko a cikin manyan tashoshi, don haka baiwa kayan aiki tare da kyakkyawan aikin fitarwa. Sabanin haka, tashoshi na lithium - ion diffusion tashoshi a cikin lithium iron phosphate kayan aiki ne daya - girma, ma'ana cewa a cikin crystal akwai kawai "tunnel" don lithium - ion diffusion, don haka lithium - ƙaura na lithium ya ɗan yi jinkiri kuma nisan yadawa gajeru ne. Musamman a ƙarƙashin yanayin fitarwa mai girma -, ions lithium na ciki ba zai iya yin ƙaura cikin lokaci ba, yana haifar da gagarumin juzu'i na electrochemical.
Ana iya ƙirƙira batura ta amfani da tsantsar kayan ƙarfe na phosphate na lithium don tabbatar da ƙarshe na sama. Gwaje-gwaje sun nuna cewa ƙarfin yin amfani da tsantsar kayan aikin phosphate na lithium baƙin ƙarfe ba shi da ƙarfi sosai, kuma baturin yana samun saurin lalacewa yayin hawan keke. Hoto 2.1 yana nuna aikin hawan keke na tantanin sigar tsabar kudin lithium{3} ion wanda marubucin ya yi ta amfani da sinadarin hydrothermally synthesized pure lithium iron phosphate (ba tare da murfin carbon ba). Ana iya ganin cewa bayan kusan zagayowar caji-15, ƙarfin baturi ya lalace da fiye da kashi 20%. Don haka, tsarkakakken kayan phosphate na lithium baƙin ƙarfe bai dace da tsarin batirin lithium{8}}ion ba.
A shekara ta 2000, Hydro{1}Québec (H{2}}Q), ma'aikatar jama'a ta Kanada, ita ce ta farko da ta fara ba da takardun haƙƙin mallaka kan shafi lithium baƙin ƙarfe phosphate tare da kayan sarrafawa, gami da yin amfani da murfin carbon akan kayan ƙarfe na ƙarfe na lithium. Wannan ya ba lithium baƙin ƙarfe phosphate damar cimma takamaiman iya aiki kuma ya tsawaita rayuwarsa zuwa fiye da 2000 hawan keke. Wannan ya nuna farkon tsarin masana'antu na lithium iron phosphate a matsayin kayan cathode.
