Kedu ihe kpatara batrị lithium iron phosphate ji ada ada?
By hoppt
Ịghọta ihe kpatara ma ọ bụ usoro ọdịda nke batrị lithium iron phosphate dị ezigbo mkpa maka imeziwanye arụmọrụ batrị yana nnukwu mmepụta na ojiji ya. Edemede a na-atụle mmetụta adịghị ọcha, ụzọ nhazi, ọnọdụ nchekwa, imegharị ihe, chaja karịrị, na ịwụfu oke na ọdịda batrị.
1. Ọdịda na usoro mmepụta
Na usoro mmepụta, ndị ọrụ, akụrụngwa, akụrụngwa, ụzọ na gburugburu ebe obibi bụ isi ihe na-emetụta àgwà ngwaahịa. Na mmepụta nke LiFePO4 batrị ike, ndị ọrụ na akụrụngwa bụ nke akporo management, otú anyị tumadi na-atụle ikpeazụ atọ mmetụta ihe.
Ọdịghị ọcha dị na ihe electrode na-arụ ọrụ na-akpata ọdịda nke batrị.
N'oge njikọ nke LiFePO4, a ga-enwe ọnụ ọgụgụ dị nta nke adịghị ọcha dị ka Fe2O3 na Fe. A ga-ebelata ihe adịghị ọcha ndị a n'elu electrode na-adịghị mma ma nwee ike dụpuo diaphragm ma mee ka mkpirisi dị n'ime. Mgbe ekpughere LiFePO4 na ikuku ruo ogologo oge, mmiri ga-emebi batrị. N'oge mmalite nke ịka nká, a na-emepụta phosphate amorphous n'elu ihe ahụ. Ngwakọta na nhazi mpaghara ya yiri LiFePO4(OH); na ntinye nke OH, LiFePO4 na-aga n'ihu na-eri ya, Na-egosipụta dị ka mmụba nke olu; emesia recrystallized nwayo ka ọ bụrụ LiFePO4(OH). Ihe adịghị ọcha nke Li3PO4 dị na LiFePO4 bụ ihe na-adịghị ike nke electrochemically. Ka elu ọdịnaya adịghị ọcha nke graphite anode, na-abawanye ikike nke enweghị ike ịgbanwe.
Ọdịda nke batrị kpatara site na usoro nhazi
Ọnwụ lithium ion na-arụ ọrụ na-apụtaghị ìhè na mbụ na ion lithium riri mgbe ọ na-akpụ akpụkpọ ahụ siri ike nke electrolyte interfacial. Nnyocha achọpụtala na ịba ụba nke ọnọdụ okpomọkụ ga-eme ka mfu nke ion lithium na-enweghị ike ịgbanwe. Mgbe e guzobere okpomọkụ na-abawanye, nkezi nke inorganic components na SEI film ga-abawanye. The gas ewepụtara n'oge mgbanwe si organic akụkụ ROCO2Li na inorganic akụrụngwa Li2CO3 ga-eme ka ndị ọzọ ntụpọ na SEI nkiri. Ọnụ ọgụgụ buru ibu nke ion lithium edoziworo site na ntụpọ ndị a ga-etinye na electrode graphite na-adịghị mma.
N'oge e guzobere, ihe mejupụtara na ọkpụrụkpụ nke ihe nkiri SEI nke emere site na chaja dị ala ugbu a bụ otu ma na-ewe oge; Nchaji dị elu ugbu a ga-eme ka mmeghachi omume dị n'akụkụ na-eme, na-ebute ụba lithium-ion na-enweghị ike ịgbagha na ihe mgbochi electrode na-adịghị mma ga-abawanye, ma ọ na-azọpụta oge. Oge; N'oge ugbu a, e guzobere mode nke obere ugbu a na-adịgide adịgide ugbu a-nnukwu ugbu a na-adịgide adịgide ugbu a na mgbe niile voltaji na-eji ugboro ugboro nke mere na ọ pụrụ iburu uru nke ma n'ime akaụntụ.
Ọdịda batrị kpatara site na mmiri dị na gburugburu mmepụta
Na mmepụta n'ezie, batrị ga-akpọtụrụ ikuku n'ihi na ihe ndị dị mma na ndị na-adịghị mma bụ ihe kachasị micron ma ọ bụ nano-sized particles, na ihe mgbaze dị na electrolyte nwere nnukwu electronegative carbonyl otu na metastable carbon-carbon okpukpu abụọ. Niile na-adị mfe itinye mmiri na ikuku.
Mkpụrụ ndụ mmiri na-emeghachi omume na nnu lithium (karịsịa LiPF6) na electrolyte, nke na-erepịa ma na-erepịa electrolyte (decompose to form PF5) ma na-emepụta ihe acidic HF. Ma PF5 na HF ga-ebibi ihe nkiri SEI, na HF ga-akwalitekwa corrosion nke LiFePO4 ihe na-arụ ọrụ. Mkpụrụ ndụ mmiri ga-emebikwa electrode ọjọọ nke lithium-intercalated graphite, na-akpụ lithium hydroxide na ala nke ihe nkiri SEI. Na mgbakwunye, O2 etisasịwo na electrolyte ga-eme ngwangwa ịka nká nke Batrị LiFePO4.
N'ime usoro mmepụta ihe, na mgbakwunye na usoro mmepụta nke na-emetụta arụmọrụ batrị, isi ihe na-akpata ọdịda nke batrị LiFePO4 na-agụnye ihe ndị na-adịghị ọcha na ihe ndị dị na ngwaahịa (gụnyere mmiri) na usoro nhazi, ya mere ịdị ọcha nke ihe onwunwe, njikwa nke iru mmiri gburugburu ebe obibi, usoro nhazi, wdg. Ihe ndị dị oké mkpa.
2. Ọdịda na shelf
N'oge ndụ batrị ike ọrụ, ọtụtụ oge ya na-anọ n'ọnọdụ nchekwa. N'ozuzu, mgbe ogologo oge nchekwa gachara, ịrụ ọrụ batrị ga-ebelata, na-egosipụtakarị mmụba nke nguzogide dị n'ime, mbelata voltaji, na mbelata nke ikike mwepu. Ọtụtụ ihe na-ebute mmebi nke arụmọrụ batrị, nke ọnọdụ okpomọkụ, ọnọdụ ụgwọ, na oge bụ ihe kacha emetụta.
Kasem et al. nyochaa ịka nká nke batrị ike LiFePO4 n'okpuru ọnọdụ nchekwa dị iche iche. Ha kwenyere na usoro ịka nká bụ akụkụ mmeghachi omume nke electrodes dị mma na nke na-adịghị mma. The electrolyte (tụnyere mmeghachi omume n'akụkụ nke nti electrode, akụkụ mmeghachi omume nke graphite electrode na-adịghị mma bụ arọ, tumadi kpatara ihe mgbaze. Decomposition, uto nke SEI film) na-erepịakwa ọrụ lithium ion. N'otu oge ahụ, ngụkọta mgbochi nke batrị na-abawanye, mfu nke ion lithium na-arụ ọrụ na-eduga na ịka nká batrị mgbe ọ hapụrụ. Ọnwụ ikike nke batrị LiFePO4 na-abawanye na ịrị elu nke okpomọkụ nchekwa. N'ụzọ dị iche, ka ọnọdụ nchekwa nke ụgwọ na-abawanye, mfu ikike dị ntakịrị.
Grolleau et al. rutekwara otu nkwubi okwu ahụ: okpomọkụ nchekwa na-enwe mmetụta dị ịrịba ama na ịka nká nke batrị LiFePO4, na-esote ọnọdụ nchekwa nke ụgwọ, na-atụ aro ihe nlereanya dị mfe. Ọ nwere ike ibu amụma ọnwụ ike nke batrị ike LiFePO4 dabere na ihe ndị metụtara oge nchekwa (okpomọkụ na ọnọdụ ụgwọ). Na steeti SOC akọwapụtara, ka oge shelf na-abawanye, lithium dị na graphite ga-agbasa na nsọtụ, na-eme ka ngwakọta dị mgbagwoju anya na electrolyte na electrons, na-ebute mmụba na nha nke ion lithium na-enweghị ike ịgbanwe, na-agbatị SEI, na conductivity. Mmụba nke impedance kpatara mbelata (ihe ndị inorganic na-abawanye, ụfọdụ nwere ohere ịgbaze) yana mbelata ọrụ elu electrode ọnụ na-eme ka batrị ahụ ka nká.
N'agbanyeghị ọnọdụ ịchaji ma ọ bụ ọnọdụ nkwụsịtụ, calorimetry dị iche iche nyocha ahụ ahụghị mmeghachi omume ọ bụla n'etiti LiFePO4 na electrolytes dị iche iche (electrolyte bụ LiBF4, LiAsF6, ma ọ bụ LiPF6) na okpomọkụ sitere na ọnụ ụlọ ruo 85 ° C. Otú ọ dị, mgbe LiFePO4 na-emikpu na electrolyte nke LiPF6 ruo ogologo oge, ọ ka ga-egosipụta kpọmkwem reactivity. N'ihi na mmeghachi omume na-etolite interface na-adịte aka, a ka nwere ihe nkiri passivation n'elu LiFePO4 iji gbochie mmeghachi omume ọzọ na electrolyte mgbe imikpu maka otu ọnwa.
Na steeti nchekwa, ọnọdụ nchekwa na-adịghị mma (oke okpomọkụ na ọnọdụ ụgwọ dị elu) ga-eme ka ogo nke ịwepu onwe ya nke batrị LiFePO4, na-eme ka batrị ahụ na-aka nká pụta ìhè.
3. Ọdịda na imegharị ihe
Batrị na-ebutekarị okpomọkụ n'oge a na-eji ya eme ihe, ya mere mmetụta nke okpomọkụ dị ịrịba ama. Na mgbakwunye, ọnọdụ okporo ụzọ, ojiji, na ọnọdụ okpomọkụ ga-enwe mmetụta dị iche iche.
Ọnwụ nke ion lithium na-arụ ọrụ n'ozuzu na-ebute mfu ikike nke batrị LiFePO4 n'oge ịgba ígwè. Dubarry et al. gosiri na ịka nká nke batrị ike LiFePO4 n'oge ịnya igwe na-abụkarị n'ihi usoro uto dị mgbagwoju anya nke na-eri ihe nkiri lithium-ion SEI na-arụ ọrụ. N'ime usoro a, mfu nke ion lithium na-arụ ọrụ na-ebelata ọnụ ọgụgụ njide nke ikike batrị; ọganihu na-aga n'ihu nke ihe nkiri SEI, n'otu aka, na-eme ka mmụba nke polarization na-eguzogide batrị. N'otu oge ahụ, ọkpụrụkpụ nke ihe nkiri SEI dị oke oke, na ọrụ electrochemical nke graphite anode. Ọ ga-eme ka ọrụ ahụ kwụsị ọrụ.
N'oge ịnya igwe na-ekpo ọkụ, Fe2+ na LiFePO4 ga-agbaze ruo n'ókè ụfọdụ. Ọ bụ ezie na ọnụ ọgụgụ nke Fe2 + gbazere enweghị mmetụta dị ịrịba ama na ikike nke electrode dị mma, mgbasa nke Fe2 + na ọdịda nke Fe na electrode graphite na-adịghị mma ga-arụ ọrụ catalytic na uto nke ihe nkiri SEI. . Tan quantitatively tụlere ebe na ebe lithium ion na-arụ ọrụ na-efunahụ wee chọpụta na ọtụtụ n'ime mfu nke lithium ion nọ n'ọrụ mere n'elu nke electrode graphite na-adịghị mma, karịsịa n'oge usoro okpomọkụ dị elu, ya bụ, mfu ikike okirikiri okpomọkụ dị elu. dị ngwa ngwa, ma chịkọta ihe nkiri SEI E nwere ụzọ atọ dị iche iche nke mmebi na nrụzi:
- Eletrọn na graphite anode na-agafe ihe nkiri SEI iji belata ion lithium.
- Mgbasa na mweghachi nke ụfọdụ akụkụ nke ihe nkiri SEI.
- N'ihi mgbanwe olu nke graphite anode, akpụkpọ ahụ SEI kpatara mgbawa.
Na mgbakwunye na mfu nke ion lithium na-arụ ọrụ, ma ihe ndị dị mma na nke na-adịghị mma ga-akawanye njọ n'oge a na-emegharị ihe. Ihe omume nke mgbawa na LiFePO4 electrode n'oge imegharị ihe ga-eme ka electrode polarization na-abawanye na conductivity n'etiti ihe na-arụ ọrụ na onye na-eduzi ma ọ bụ onye nchịkọta ugbu a na-ebelata. Nagpure ji Scanning Extended Resistance Microscope (SSRM) mee nyocha nke ọkara-quantitatively na-amụ mgbanwe nke LiFePO4 mgbe ịka nká wee chọpụta na coarsening nke LiFePO4 nanoparticles na elu nkwụnye ego mepụtara kpọmkwem kemịkalụ mmeghachi omume ọnụ butere mmụba na impedance nke LiFePO4 cathodes. Tụkwasị na nke ahụ, a na-ewerekwa mbelata elu na-arụ ọrụ na nkwụsị nke electrodes graphite nke na-efunahụ ihe na-arụ ọrụ graphite na-ewerekwa na ọ bụ ihe kpatara ịka nká batrị. Enweghi ike nke graphite anode ga-eme ka enweghi ike nke ihe nkiri SEI ma kwalite oriri nke ion lithium na-arụ ọrụ.
Mwepu dị elu nke batrị nwere ike inye ike dị mkpa maka ụgbọ ala eletrik; ya bụ, ka mma na-arụ ọrụ ọnụego nke batrị ike, ka mma na-arụ ọrụ osooso nke ụgbọ ala eletrik. Nsonaazụ nyocha nke Kim et al. gosiri na usoro ịka nká nke LiFePO4 mma electrode na graphite ọjọọ electrode dị iche iche: na-abawanye nke mwepu ọnụego, ikike ọnwụ nke nti electrode na-abawanye karịa nke na-adịghị mma electrode. Ọnwụ nke ikike batrị n'oge ịgba ígwè dị obere bụ n'ihi oriri nke ion lithium na-arụ ọrụ na electrode na-adịghị mma. N'ụzọ dị iche, ọnwụ ike nke batrị n'oge ịnya igwe dị elu bụ n'ihi mmụba nke mgbochi nke electrode dị mma.
Ọ bụ ezie na omimi nke ntọhapụ nke batrị ike na-eji agaghị emetụta mfu ikike, ọ ga-emetụta ọnwụ ike ya: ọsọ nke ọnwụ ike na-abawanye na mmụba nke omimi nke nkwụsị. Nke a bụ n'ihi ịrị elu nke impedance nke ihe nkiri SEI na mmụba nke nkwụsị nke batrị dum. O metụtara ya kpọmkwem. Ọ bụ ezie na n'ihe metụtara ọnwụ nke ion lithium na-arụ ọrụ, oke elu nke chaja chaja enweghị mmetụta pụtara ìhè na ọdịda batrị, oke oke ma ọ bụ oke elu nke voltaji chaja ga-abawanye ihe mgbochi interface nke LiFePO4 electrode: obere elu dị elu. oke voltaji agaghị arụ ọrụ nke ọma. A na-emepụta ihe nkiri passivation na ala, na oke oke voltaji dị elu ga-eme ka oxidative Decomposition nke electrolyte. Ọ ga-emepụta ngwaahịa nwere obere conductivity n'elu nke LiFePO4 electrode.
Ike mwepu nke batrị ike LiFePO4 ga-ada ngwa ngwa mgbe okpomọkụ na-ebelata, tumadi n'ihi mbelata nke ion conductivity na mmụba nke impedance interface. Li mụrụ LiFePO4 cathode na graphite anode iche iche wee chọpụta na isi ihe na-achịkwa ihe na-egbochi obere okpomọkụ nke anode na anode dị iche iche. Mbelata nke ionic conductivity nke LiFePO4 cathode bụ isi, yana mmụba nke mgbochi interface nke graphite anode bụ isi ihe kpatara ya.
N'oge eji, mmebi nke LiFePO4 electrode na graphite anode na ọganihu na-aga n'ihu nke ihe nkiri SEI ga-eme ka batrị ghara ịdaba na ogo dịgasị iche iche. Na mgbakwunye, na mgbakwunye na ihe ndị a na-achịkwaghị achịkwa dị ka ọnọdụ okporo ụzọ na ọnọdụ okpomọkụ, iji batrị ahụ eme ihe mgbe niile dịkwa mkpa, gụnyere voltaji chaja kwesịrị ekwesị, ihe omimi kwesịrị ekwesị nke nkwụsị, wdg.
4. ọdịda n'oge ịchaji na ịchaji
A na-enwekarị chajịja karịa batrị mgbe eji ya. Ọ na-adị ntakịrị nfefe. Okpomọkụ a na-ewepụta n'oge chaja karịrị akarị ma ọ bụ nfefe ya nwere ike ịgbakọta n'ime batrị, na-abawanye okpomọkụ batrị. Ọ na-emetụta ndụ ọrụ batrị ma na-ebulite ohere nke ọkụ ma ọ bụ mgbawa nke oké ifufe ahụ. Ọbụlagodi n'okpuru nchaji na ọnọdụ ịgbasa mgbe niile, ka ọnụọgụ nke okirikiri na-abawanye, ikike ekwekọghị ekwekọ nke otu sel na sistemụ batrị ga-abawanye. Batrị nwere ikike kacha nta ga-aga n'ihu usoro chaja na chaja karịa.
Ọ bụ ezie na LiFePO4 nwere nkwụsi ike okpomọkụ kachasị mma ma e jiri ya tụnyere ihe ndị ọzọ dị mma electrode n'okpuru ọnọdụ chajị dị iche iche, ịchaji nwere ike ịkpata ihe egwu na-adịghị ize ndụ na iji batrị LiFePO4. N'ime steeti a na-ebufe ibu, ihe mgbaze dị na electrolyte organic na-adịkarị mfe nbibi oxidative. N'ime ihe mgbaze organic a na-ejikarị, ethylene carbonate (EC) ga-akacha mma nweta nbibi oxidative n'elu electrode dị mma. Ebe ikike ntinye lithium (gagidere ikike lithium) nke electrode graphite na-adịghị mma bụ nke na-emighị emi, oke mmiri ozuzo lithium nwere ike ịbụ na electrode graphite na-adịghị mma.
Otu n'ime isi ihe kpatara ọdịda batrị n'okpuru ọnọdụ chajịja karịrị akarị bụ sekit dị mkpụmkpụ dị n'ime nke alaka lithium kristal na-akpupu diaphragm. Lu et al. nyochara usoro ọdịda nke lithium plating n'elu graphite na-emegide electrode elu nke chaja karịrị akarị kpatara. Nsonaazụ gosiri na n'ozuzu Ọdịdị nke graphite electrode na-adịghị mma agbanwebeghị, ma e nwere lithium crystal alaka na elu film. Mmeghachi omume nke lithium na electrolyte na-eme ka ihe nkiri elu na-abawanye na-aga n'ihu, nke na-eri lithium na-arụsi ọrụ ike ma na-eme ka lithium gbasaa n'ime graphite. Igwe electrode na-adịghị mma na-aghọwanye mgbagwoju anya, nke ga-eme ka ntinye nke lithium dịkwuo elu n'elu electrode na-adịghị mma, na-eme ka mbelata ọzọ na ikike na coulombic arụ ọrụ.
Na mgbakwunye, a na-ewerekarị adịghị ọcha igwe (karịsịa Fe) dị ka otu n'ime ihe kpatara ọdịda batrị karịrị akarị. Xu et al. mụọ nke ọma na usoro ọdịda nke batrị LiFePO4 n'okpuru ọnọdụ chajị karịrị akarị. Nsonaazụ na-egosi na redox nke Fe n'oge nkwụghachi ụgwọ / nkwụghachi ụgwọ ga-ekwe omume, a na-enyekwa usoro mmeghachi omume. Mgbe ịchaji gafere, Fe na-ebu ụzọ oxidized na Fe2+, Fe2+ na-akawanye njọ na Fe3+, wee wepụ Fe2+ na Fe3+ na electrode dị mma. Otu akụkụ na-agbasa n'akụkụ electrode na-adịghị mma, Fe3+ na-emesị belata na Fe2+, na Fe2+ na-ebelata ka ọ bụrụ Fe; mgbe overcharge / igbapu cycles, Fe crystal alaka ga-amalite na nti na-adịghị mma electrodes n'otu oge ahụ, edupuo separator na-emepụta Fe àkwà mmiri, dapụtara na micro batrị Short sekit, ihe pụtara ìhè na-eso batrị micro short circuit bụ na-aga n'ihu. mmụba na okpomọkụ mgbe ịchachachara.
N'oge oke ibu, ikike nke electrode na-adịghị mma ga-ebili ngwa ngwa. Mmụba nwere ike ibibi ihe nkiri SEI n'elu electrode na-adịghị mma (akụkụ bara ụba na ogige inorganic na ihe nkiri SEI nwere ike ịbụ oxidized), nke ga-eme ka ọzọ Decomposition nke electrolyte, na-akpata nkwụsị nke ikike. Nke kachasị mkpa, onye na-anakọta ihe na-adịghị mma Cu foil ga-abụ oxidized. Na ihe nkiri SEI nke electrode na-adịghị mma, Yang et al. achọpụtara Cu2O, ngwaahịa oxidation nke Cu foil, nke ga-eme ka batrị dị n'ime ya dịkwuo elu ma mee ka oke ifufe ahụ kwụsịlata.
Ọ et al. mụọ usoro nfefe karịrị nke batrị LiFePO4 n'uju. Nsonaazụ gosiri na onye na-anakọta ihe na-adịghị mma Cu foil nwere ike oxidized na Cu + n'oge ịwepu oke, na Cu+ na-agakwa n'ihu na Cu2+, mgbe nke ahụ gasịrị, ha na-agbasa na electrode dị mma. Mbelata mmeghachi omume nwere ike ime na electrode dị mma. N'ụzọ dị otú a, ọ ga-etolite kristal alaka na nti electrode n'akụkụ, dupuo separator na-eme ka a micro short circuit n'ime batrị. Ọzọkwa, n'ihi nchafu oke, okpomọkụ batrị ga-aga n'ihu na-ebili.
Nfefe batrị ike LiFePO4 nwere ike ime ka oxidative electrolyte decomposition, lithium evolushọn, na guzobe nke Fe kristal alaka; nfefe n'elu nwere ike ime ka mmebi SEI, na-ebute mmebi ikike, Cu foil oxidation, na ọbụna ọdịdị Cu alaka kristal.
5. ọdịda ndị ọzọ
N'ihi ọdịdị dị ala dị ala nke LiFePO4, morphology na nha nke ihe ahụ n'onwe ya na mmetụta nke ndị na-emepụta ihe na ndị na-ejikọta ya na-apụta ngwa ngwa. Gaberscek et al. atụle abụọ emegiderịta ihe nke size na carbon mkpuchi na chọpụtara na electrode impedance nke LiFePO4 bụ nanị metụtara nkezi urughuru size. Mmebi mgbochi saịtị na LiFePO4 (Fe occupies Li sites) ga-enwe mmetụta pụrụ iche na arụmọrụ batrị: n'ihi na nnyefe nke ion lithium n'ime LiFePO4 bụ otu akụkụ, ntụpọ a ga-egbochi nkwurịta okwu nke ion lithium; n'ihi iwebata steeti valence dị elu N'ihi mgbagha electrostatic agbakwunyere, ntụpọ a nwekwara ike ime ka enweghị ntụkwasị obi nke usoro LiFePO4.
Nnukwu irighiri ihe nke LiFePO4 enweghị ike inwe obi ụtọ na njedebe nke ịchaji; nano-ahazi LiFePO4 nwere ike ibelata mmebi ngbanwe, ma ike elu ya dị elu ga-eme ka ịwepụ onwe ya. PVDF bụ ihe nkedo a na-ejikarị eme ihe ugbu a, nke nwere adịghị ike dị ka mmeghachi omume na okpomọkụ dị elu, mgbasa na electrolyte na-abụghị mmiri, na enweghị mgbanwe zuru oke. Ọ nwere mmetụta pụrụ iche na ọnwụ ikike na ndụ okirikiri nke LiFePO4. Na mgbakwunye, onye na-anakọta ugbu a, diaphragm, ihe mejupụtara electrolyte, usoro mmepụta, ihe mmadụ na-akpata, ịma jijiji nke mpụga, ujo, wdg, ga-emetụta arụmọrụ batrị na ogo dị iche iche.
Ntụaka: Miao Meng et al. "Ọganihu nyocha na ọdịda nke batrị ike batrị nke Lithium Iron Phosphate."
