N'ebe ọnọdụ okpomọkụ dị ala, ịrụ ọrụ batrị lithium-ion adịghị mma.Mgbe batrị lithium-ion a na-ejikarị na-arụ ọrụ na -10 Celsius C, a ga-ebelata ụgwọ kachasị elu na ikike mwepu na voltaji ọdụ ụgbọ elu ma e jiri ya tụnyere okpomọkụ nkịtị [6], mgbe okpomọkụ ntọhapụ dara na -20 Celsius C, ikike dịnụ ga-ebelata. ọbụna na-ebelata ka 1/3 na ụlọ okpomọkụ 25 Celsius C, mgbe mwepu okpomọkụ dị ala, ụfọdụ batrị lithium apụghị ọbụna chajị na mwepu ọrụ, na-abanye a "batrị nwụrụ anwụ" steeti.
1, Njirimara nke batrị lithium-ion na obere okpomọkụ
(1) Macroscopic
Mgbanwe njirimara nke batrị lithium-ion na obere okpomọkụ dị ka ndị a: na mbelata okpomọkụ na-aga n'ihu, nkwụsị ohmic na nkwụsị nke polarization na-abawanye na ogo dị iche iche;Voltage mwepu nke batrị lithium-ion dị ala karịa nke okpomọkụ nkịtị.Mgbe ị na-ebugharị ma na-ebugharị na obere okpomọkụ, voltaji arụ ọrụ ya na-ebili ma ọ bụ daa ngwa ngwa karịa nke ahụ na okpomọkụ nkịtị, na-ebute mbelata dị ukwuu na ikike na ike ya kacha.
(2) N'ile anya
Mgbanwe arụmọrụ nke batrị lithium-ion na obere okpomọkụ bụ n'ihi mmetụta nke ihe ndị a dị mkpa.Mgbe ọnọdụ okpomọkụ dị ala karịa -20 ℃, mmiri mmiri electrolyte na-esiwanye ike, viscosity ya na-abawanye nke ọma, na ionic conductivity na-ebelata.Mgbasa lithium ion na ihe electrode dị mma na nke na-adịghị mma bụ ngwa ngwa;Lithium ion siri ike ịtọgbọrọ n'efu, na nnyefe ya na ihe nkiri SEI na-adị ngwa ngwa, na nkwụsị nnyefe ụgwọ na-abawanye.Nsogbu lithium dendrite bụ nke a ma ama na obere okpomọkụ.
2, Iji dozie obere okpomọkụ arụmọrụ nke lithium-ion batrị
Chepụta usoro mmiri mmiri electrolytic ọhụrụ iji zute ọnọdụ okpomọkụ dị ala;Meziwanye ihe owuwu electrode dị mma na nke na-adịghị mma iji mee ka ọsọ nke nnyefe dị ngwa ma belata ebe nnyefe;Jikwaa interface electrolyte siri ike na nke na-adịghị mma iji belata mgbochi.
(1) ihe mgbakwunye electrolyte
N'ozuzu, iji ihe mgbakwunye na-arụ ọrụ bụ otu n'ime ụzọ kachasị dị irè na nke akụ na ụba iji meziwanye arụmọrụ dị ala nke batrị ma nyere aka ịmepụta ihe nkiri SEI dị mma.Ka ọ dị ugbu a, ụdị ihe mgbakwunye bụ isi bụ mgbakwunye isocyyanate, ihe mgbakwunye sọlfọ, ihe mgbakwunye mmiri ionic na mgbakwunye nnu lithium inorganic.
Dị ka ihe atụ, dimethyl sulfite (DMS) sọlfọ dabeere mgbakwunye, na kwesịrị ekwesị mbenata ọrụ, na n'ihi na ya Mbelata ngwaahịa na lithium ion njikọ ike ike karịa vinyl sulfate (DTD), ibelata ojiji nke organic mgbakwunye ga-amụba interface impedance, na-ewu a. ọzọ kwụsiri ike na mma ionic conductivity nke na-adịghị mma electrode interface film.Sulfite esters nke dimethyl sulfite (DMS) nọchiri anya ya nwere oke dielectric na-adịgide adịgide yana oke okpomọkụ na-arụ ọrụ.
(2) Ihe mgbaze nke electrolyte
The omenala lithium-ion batrị electrolyte bụ igbari 1 mol nke lithium hexafluorophosphate (LiPF6) n'ime agwakọta ihe mgbaze, dị ka EC, PC, VC, DMC, methyl ethyl carbonate (EMC) ma ọ bụ diethyl carbonate (DEC), ebe mejupụtara. ihe mgbaze, ebe mgbaze, dielectric mgbe niile, viscosity na ndakọrịta na nnu lithium ga-emetụta oke okpomọkụ nke batrị ahụ.Ka ọ dị ugbu a, electrolyte azụmahịa dị mfe ịkwado mgbe etinyere ya na ọnọdụ okpomọkụ dị ala nke -20 ℃ na n'okpuru, obere dielectric mgbe niile na-eme ka nnu lithium siri ike ịgbasa, na viscosity dị oke elu iji mee ka batrị dị n'ime ya na-eguzogide ma dị ala. ikpo okwu voltaji.Batrị lithium-ion nwere ike ịrụ ọrụ dị ala karịa nke ọma site n'ịkwalite usoro ihe mgbaze dị ugbu a, dị ka site n'ịkwalite usoro electrolyte (EC: PC: EMC = 1: 2: 7) nke mere na TiO2 (B) / graphene ọjọọ electrode nwere A. ikike nke ~ 240 mA h g-1 na -20 ℃ na 0.1 A g-1 njupụta ugbu a.Ma ọ bụ mepụta ihe mgbaze electrolyte dị ala ọhụrụ.The ogbenye arụmọrụ nke lithium-ion batrị na obere okpomọkụ bụ tumadi metụtara ngwa ngwa tọgbọrọ n'efu nke Li + n'oge usoro nke Li + embeding na electrode ihe.Enwere ike ịhọrọ ihe ndị nwere obere ike njikọ dị n'etiti Li + na ụmụ irighiri ihe mgbaze, dị ka 1, 3-dioxopentylene (DIOX), na nanoscale lithium titanate na-eji ihe elektrọd iji kpokọta ule batrị iji kwụọ ụgwọ maka mbelata mgbasa nke ọnụọgụ nke electrode ihe na ultra-obere okpomọkụ, nke mere na iji nweta mma ala-okpomọkụ arụmọrụ.
(3) nnu lithium
Ka ọ dị ugbu a, LiPF6 ion nke azụmahịa nwere ikike dị elu, mmiri dị elu chọrọ na gburugburu ebe obibi, nkwụsi ike ọkụ na-adịghị mma, na ikuku ọjọọ dị ka HF na mmeghachi omume mmiri dị mfe ime ihe egwu nchekwa.Ihe nkiri electrolyte siri ike mepụtara site na lithium difluoroxalate borate (LiODFB) kwụsiri ike ma nwee arụmọrụ dị ala dị ala karịa yana arụmọrụ dị elu.Nke a bụ n'ihi na LiODFB nwere uru nke ma lithium dioxalate borate (LiBOB) na LiBF4.
3. Nchịkọta
Obere okpomọkụ nke batrị lithium-ion ga-emetụta ọtụtụ akụkụ dị ka ihe electrode na electrolytes.Ọganihu zuru oke site n'ọtụtụ echiche dị ka ihe electrode na electrolyte nwere ike ịkwalite ngwa na mmepe nke batrị lithium-ion, na atụmanya ngwa nke batrị lithium dị mma, ma nkà na ụzụ kwesịrị ịmepụta na zuru oke na nyocha ọzọ.
Oge nzipu: Jul-27-2023