ʻO ka hana haʻahaʻa haʻahaʻa o nā pā lithium

Ma ke kaiapuni haʻahaʻa haʻahaʻa, ʻaʻole kūpono ka hana pākaukau lithium-ion.Ke hoʻohana maʻamau ʻia nā pākaukau lithium-ion ma -10 ° C, e hoʻemi nui ʻia ko lākou uku kiʻekiʻe a me ka hoʻokuʻu ʻana a me ka voltage terminal e hoʻohālikelike ʻia me ka mahana maʻamau [6], ke hāʻule ka mahana hoʻokuʻu i -20 ° C, e loaʻa ka mana i loaʻa. hiki ke ho'ēmi i ka 1/3 ma ka lumi wela 25 ° C, i ka wā e emi iho ai ka mahana hoʻokuʻu, ʻaʻole hiki i kekahi mau pahu lithium ke hoʻouka a hoʻokuʻu i nā hana, e komo ana i kahi mokuʻāina "make".

1, ʻO nā hiʻohiʻona o nā pā lithium-ion i nā haʻahaʻa haʻahaʻa
(1) Macroscopic
ʻO nā hoʻololi hiʻohiʻona o ka pā lithium-ion i ka haʻahaʻa haʻahaʻa e like me kēia: me ka emi mau o ka mahana, piʻi ka ohmic resistance a me ka polarization resistance i nā degere like ʻole;ʻOi aku ka haʻahaʻa o ka volta hoʻokuʻu o ka pā lithium-ion ma mua o ka mahana maʻamau.I ka hoʻouka ʻana a me ka hoʻokuʻu ʻana i ka haʻahaʻa haʻahaʻa, piʻi a hāʻule paha kona voli hana ma mua o ka mahana maʻamau, e hopena i ka emi nui o kona hiki ke hoʻohana a me ka mana.

(2) Ma ke ʻano liʻiliʻi
ʻO ka hoʻololi ʻana i ka hana o nā pā lithium-ion i nā haʻahaʻa haʻahaʻa ma muli o ka mana o nā mea nui e hiki mai ana.Ke emi iho ka mahana ambient ma mua o -20 ℃, paʻa ka wai electrolyte, piʻi nui kona viscosity, a emi iho kona conductivity ionic.Ua lohi ka hoʻoheheʻe ʻana o ka lithium ion i nā mea electrode maikaʻi a maikaʻi ʻole;He paʻakikī ke hoʻopau ʻana i ka lithium ion, a ua lohi kona lawe ʻana i ke kiʻiʻoniʻoni SEI, a piʻi aʻe ka impedance hoʻoili.ʻO ka pilikia lithium dendrite e koʻikoʻi loa i ka haʻahaʻa haʻahaʻa.

2, No ka hoʻoponopono i ka haʻahaʻa haʻahaʻa haʻahaʻa haʻahaʻa o nā pā lithium-ion
E hoʻolālā i kahi ʻōnaehana wai electrolytic hou e hoʻokō i ke kaiapuni haʻahaʻa haʻahaʻa;E hoʻomaikaʻi i ka hoʻolālā electrode maikaʻi a maikaʻi ʻole e hoʻolōʻihi i ka wikiwiki o ka hoʻouna ʻana a hoʻopōkole i ka mamao hoʻouna;E hoʻomalu i ka pilina electrolyte paʻa maikaʻi a maikaʻi ʻole e hōʻemi i ka impedance.

(1) nā mea hoʻohui electrolyte
Ma keʻano laulā, ʻo ka hoʻohana ʻana i nā mea hoʻohui hana ʻo ia kekahi o nā ala ʻoi aku ka maikaʻi a me ka waiwai e hoʻomaikaʻi ai i ka hana haʻahaʻa haʻahaʻa o ka pākaukau a kōkua i ke kūkulu ʻana i ke kiʻiʻoniʻoni SEI kūpono.I kēia manawa, ʻo nā ʻano mea hoʻohui nui he isocyanate based additives, sulfur based additives, ionic liquid additives a me inorganic lithium salt additives.

No ka laʻana, dimethyl sulfite (DMS) sulfur mea hoʻohui, me ka hana hoʻohaʻahaʻa kūpono, a no ka mea, ʻoi aku ka nāwaliwali o kāna mau huahana hoʻemi a me ka paʻa ʻana o ka lithium ion ma mua o ka vinyl sulfate (DTD), e hoʻohaʻahaʻa i ka hoʻohana ʻana i nā mea hoʻohui kūlohelohe e hoʻonui i ka impedance interface, e kūkulu i kahi ʻoi aku ka paʻa a ʻoi aku ka maikaʻi o ka conductivity ionic o ke kiʻi ʻoniʻoni electrode maikaʻi ʻole.ʻO nā esters sulfite i hōʻike ʻia e ka dimethyl sulfite (DMS) he kiʻekiʻe dielectric mau a ākea ka pae wela hana.

(2) Ka solvent o ka electrolyte
ʻO ka electrolyte pākaukau lithium-ion maʻamau e hoʻoheheʻe i 1 mol o ka lithium hexafluorophosphate (LiPF6) i loko o kahi mea hoʻoheheʻe hui ʻia, e like me EC, PC, VC, DMC, methyl ethyl carbonate (EMC) a i ʻole diethyl carbonate (DEC), kahi i hoʻokumu ʻia ai. ʻo ka solvent, melting point, dielectric constant, viscosity a me ka hoʻohālikelike ʻana me ka paʻakai lithium e hoʻopilikia koʻikoʻi i ka mahana hana o ka pā.I kēia manawa, maʻalahi ka hoʻopaʻa ʻana o ka electrolyte pāʻoihana ke hoʻopili ʻia i ka haʻahaʻa haʻahaʻa haʻahaʻa o -20 ℃ a ma lalo, ʻo ka haʻahaʻa dielectric paʻakikī e paʻakikī ke hoʻokaʻawale i ka paʻakai lithium, a ʻoi aku ka kiʻekiʻe o ka viscosity e hana i ka pākaukau kūloko a haʻahaʻa. paepae uila.Hiki i nā pila Lithium-ion ke loaʻa i ka hana haʻahaʻa haʻahaʻa haʻahaʻa ma o ka hoʻonui ʻana i ka ratio solvent e kū nei, e like me ka hoʻonui ʻana i ka hana electrolyte (EC:PC:EMC=1:2:7) i loaʻa iā TiO2(B)/graphene negative electrode A ka mana o ~240 mA h g-1 ma -20 ℃ a me 0.1 A g-1 i kēia manawa.A i ʻole e hoʻomohala i nā mea hoʻoheheʻe electrolyte haʻahaʻa haʻahaʻa hou.ʻO ka hana maikaʻi ʻole o nā pā lithium-ion i nā haʻahaʻa haʻahaʻa e pili ana i ka lohi ʻana o Li + i ka wā o ke kaʻina o Li + e hoʻokomo ʻia i ka mea electrode.Hiki ke koho ʻia nā mea me ka ikehu hoʻopaʻa haʻahaʻa ma waena o Li+ a me nā molekala solvent, e like me 1, 3-dioxopentylene (DIOX), a hoʻohana ʻia ka nanoscale lithium titanate ma ke ʻano he mea electrode e hōʻuluʻulu ai i ka hoʻāʻo ʻana i ka pākaukau e uku no ka hoʻemi o ka diffusion coefficient o ka mea electrode i nā wela haʻahaʻa haʻahaʻa, i mea e hoʻokō ai i ka hana haʻahaʻa haʻahaʻa.

(3) paʻakai lithium
I kēia manawa, he kiʻekiʻe conductivity ka ion LiPF6 pāʻoihana, koi ʻia ka maʻamau kiʻekiʻe i ke kaiapuni, maikaʻi ʻole ka thermal stability, a me nā kinoea maikaʻi ʻole e like me ka HF i ka hopena wai e maʻalahi ke kumu i nā pōʻino palekana.ʻO ke kiʻiʻoniʻoni electrolyte paʻa i hana ʻia e ka lithium difluoroxalate borate (LiODFB) he kūpaʻa paʻa a ʻoi aku ka maikaʻi o ka hana haʻahaʻa haʻahaʻa a me ka hana kiʻekiʻe.No ka mea, loaʻa iā LiODFB nā mea maikaʻi o ka lithium dioxalate borate (LiBOB) a me LiBF4.

3. Hōʻuluʻulu manaʻo
ʻO ka hana haʻahaʻa haʻahaʻa o nā pā lithium-ion e hoʻopilikia ʻia e nā ʻano he nui e like me nā mea electrode a me nā electrolytes.ʻO ka hoʻomaikaʻi piha ʻana mai nā hiʻohiʻona he nui e like me nā mea electrode a me nā electrolyte hiki ke hoʻoikaika i ka noi a me ka hoʻomohala ʻana o nā pā lithium-ion, a maikaʻi ka manaʻo noiʻi o nā pā lithium, akā pono e hoʻomohala a hoʻomaikaʻi ʻia ka ʻenehana i ka noiʻi hou aku.