ʻO ka mea cathode ke kumu mua o nā ion lithium i apākaukau lithium -ion. I ka wā o ka hoʻouka ʻana, lawe ʻia nā ion lithium mai ka lattice aniani o ka cathode a komo i ka mea anode; hiki ke hoʻololi i ka wā o ka hoʻokuʻu ʻana. ʻO ka hiki ke hoʻohuli ʻia a me ka pāpū uila o ka mea cathode i ka wā o ka hoʻouka ʻana a me ka hoʻokuʻu ʻana e hoʻoholo nui i ka nui o ka ikehu o ka pā lithium-ion. Eia kekahi, no ka mea, aia i loko o ka mea cathode nā metala e like me ka lithium, cobalt, a me ka nickel, ʻo ia ka mea nui loa o ke kumu kūʻai o kahi pākaukau lithium-ion.
ʻO ka hoʻomohala ʻana i nā mea cathode me ke kiʻekiʻe o ka ikehu kiʻekiʻe, ka uila puka kiʻekiʻe, ke ola lawelawe lōʻihi, a me ka maʻalahi o ka hana ʻana he mea nui. Pono ka mea cathode kūpono i nā kūlana kumu.
(1) Loaʻa iā ia kahi mana redox kiʻekiʻe, e hōʻoia ana i ka uila puka kiʻekiʻe no ka pākaukau.
(2) Hiki ke hoʻokomo i ka nui o nā ion lithium e like me ka hiki, e hōʻoia ana i ka nui o ka pākaukau.
(3) I ka wā o ka hoʻokomo ʻana a me ka unuhi ʻana o nā ion lithium, hiki i ka mea cathode ke mālama i kona kūpaʻa paʻa, no laila e hōʻoia i ka lōʻihi o ke ola o ka electrode.
(4) Loaʻa iā ia ka uila uila a me ka conductivity ion, e hōʻemi maikaʻi ana i ka nalowale o ka ikehu ma muli o nā hopena polarization, a laila e hōʻoiaʻiʻo ai i ka hoʻopiʻi wikiwiki a me ka hiki ke hoʻokuʻu.
(5) Pono ka pae uila hana o ka pākaukau i loko o ka laulā paʻa electrochemical o ka electrolyte, a laila e hōʻemi i nā hopena kemika pono ʻole ma waena o ka mea electrode a me ka electrolyte.
(6) ʻAʻole wale ke kumu kūʻai haʻahaʻa a me kahi kaʻina hana synthesis maʻalahi, akā pono e hōʻike i ke aloha kūlohelohe kiʻekiʻe.
Eia kekahi, pono e hōʻike ka mea cathode i ka electrochemical maikaʻi a me ke kūpaʻa wela.
Hiki ke hoʻokaʻawale ʻia nā mea cathode e kū nei i ʻekolu mau ʻāpana e pili ana i ko lākou ʻokoʻa ʻana o ka ʻano aniani: ① hale i hoʻopaʻa ʻia, e like me ka lithium cobalt oxide (LiCoO2) a me nā mea ternary (LiNiCo, Mni-x-yO2); ② hale olivine, e like me ka lithium hao phosphate (LiFePO4); ③ nā mea hoʻoheheʻe spinel, e like me ka lithium manganese oxide (LiMn2O4) a me ka lithium nickel manganese oxide (LiNi10.5Mn1.5O4). ʻO nā ʻano cathodes ʻokoʻa nā ʻano ikehu like ʻole, nā hiʻohiʻona electrochemical, a me nā kumukūʻai, i mea e kūpono ai no nā kahua like ʻole a me nā hiʻohiʻona noi. ʻO nā mea cathode hale papaʻa e pili ana i nā mea cathode me kahi ʻano microcrystalline papa, ʻo ka nui o ka lithium cobalt oxide, lithium nickel cobalt manganese oxide, a me ka lithium -rich manganese oxide. Ma waena o ia mau mea, ʻo ka lithium cobalt oxide a me ka lithium nickel cobalt manganese oxide ka mea hoʻohana nui ʻia i kēia manawa no nā ʻakika lithium-ion i nā huahana uila kikohoʻe a me nā pihi lithium{15}}ion. Hōʻike ʻia lākou e ke kiʻekiʻe o ka ikehu kiʻekiʻe, ka hana pōʻai maikaʻi, a me ka hana holoʻokoʻa maikaʻi, akā ʻo ka hapa kiʻekiʻe o nā metala e like me ka nickel, cobalt, a me ka manganese e alakaʻi i nā kumukūʻai kiʻekiʻe.
Lithium cobalt oxide cathode mea
Ua ʻike ʻia ka Lithium cobalt oxide (LiCoO2) e ka ʻepekema ʻAmelika a me ka Nobel laureate ma Chemistry, JB Goodenough, a kūʻai mua ʻia e Sony Corporation o Iapana i nā makahiki 1990. ʻOiai i kēia lā, noho mau ka lithium cobalt oxide i kekahi o nā mea cathode me ka nui o ka ikehu volumetric kiʻekiʻe. No kēia kumu, hoʻohana nui ʻia ia i nā huahana cell pouch cell e koi ai i ka nui o ka ikehu volumetric kiʻekiʻe, e like me nā kelepona paʻalima, nā wati akamai, a me nā poʻo Bluetooth.
Lithium cobalt oxide (LiCoO2), as one of the earliest commercially available cathode materials, possesses a volumetric energy density unmatched by other cathode materials. Electrodes prepared from LiCoO2 can achieve a compaction density exceeding 4.2 g/cm², and a specific capacity of 185 mA·h/g at high voltage (>4.45V). Eia kekahi, hōʻike ʻo LiCoO2 i nā hiʻohiʻona uila uila a me ka ionic, ʻoi aku ka maikaʻi o ka mana, a me ka wikiwiki -hiʻohiʻona, e hoʻokō i nā koi o nā pākahi uila mea kūʻai aku i kēia manawa a no laila e loaʻa i nā ʻano noi. Ma muli o kēia mau waiwai, noho mau ʻo LiCoO2 i kekahi o nā mea cathode maikaʻi loa a hiki i kēia lā.
ʻO nā ʻano hana synthesis nui no ka lithium cobalt oxide, ʻo ia ka -mehana solid{1}}state synthesis, sol-gel synthesis, a me ka haʻahaʻa-corecipitation wela. 'O ka ho'ohui 'ana i ka pa'akai lithium a me ka cobalt -ko'iko'i a i 'ole hydroxides i loko o ka ratio stoichiometric kiko'ī, a laila e ho'opa'a 'ia ka hui 'ana ma kahi mahana kūpono no kekahi manawa, a ma hope o ka ho'olu'u, ka pulverizing, a me ke kānana no ka loa'a 'ana o ka hāpana. ʻOiai ua hoʻohana nui ʻia ke ʻano hana synthesis mokuʻāina kiʻekiʻe -mea paʻa paʻa{10}}i ka hana ʻoihana, ʻo ia ka manawa-ʻai, koi i nā mahana synthesis kiʻekiʻe, a hoʻopuka i nā pauka like ʻole like ʻole me nā deviations stoichiometric koʻikoʻi, e hopena i ka piʻi nui ʻana o ke kumukūʻai.
ʻO nā mea cathode Phosphate
Ma 1997, Goodenough et al. ʻO ka lithium iron phosphate mua i manaʻo ʻia (LiFePO4) ma ke ʻano he mea cathode no nā pākahi lithium-ion.
Ma muli o kona kumu kūʻai haʻahaʻa, ka hale paʻa, a me ka palekana kiʻekiʻe, ua lilo kēia mea i hoʻokahi o nā mea cathode i makemake ʻia no nā pākahi lithium-ion ma nā kaʻa kaʻa uila a me nā ʻōnaehana mālama ikehu.
ʻO ka Lithium iron phosphate (LiFePO4) kaʻana like i ke ʻano aniani a me ka ʻōnaehana aniani me ka hao phosphate (FePO4). ʻO ia ke ʻano o ka loaʻa ʻana o ka hoʻololi liʻiliʻi o ka leo ma ka hoʻokomo ʻana/unuhi ʻana o ka lithium{3}}ion, me ka pale ʻana i ka pōʻino o ka lattice ma muli o ka hoʻonui ʻana a i ʻole ka hōʻemi ʻana. Eia kekahi, ʻo kēia hiʻohiʻona e hōʻoia i ka pili uila maikaʻi ma waena o nā ʻāpana a me nā mea hoʻohui conductive, e hopena i ka paʻa o ka pōʻai maikaʻi a me ke ola lōʻihi. Eia hou, kaulana ka lithium iron phosphate no kona aloha kaiapuni, -kumukūʻai, palekana maikaʻi loa, mana kikoʻī kiʻekiʻe (ma kahi o 170 mA·h/g), a me ka paepae hoʻoiho paʻa. Ma muli o kēia mau pōmaika'i, mana'o 'ia ka lithium iron phosphate he koho maika'i loa no nā mea cathode ma ka -pilikia ho'opa'a ikehu.
Aia nā kaʻina hana sol-gel, nā ʻenehana corecipitation, a me ka synthesis hydrothermal. ʻO ke kikoʻī, hoʻopuka pololei ka hydrothermal synthesis i ka huahana i hoʻopaʻa ʻia i loko o kahi autoclave ma o ka hoʻonui ʻana i ka mahana a me ke kaomi, me ka hoʻohana ʻana i ka hao, lithium, a me nā pūhui phosphorus ma ke ʻano he kumu. ʻIke ʻia kēia ʻano hana no kāna hana maʻalahi, liʻiliʻi liʻiliʻi a me ka nui o nā ʻāpana like ʻole, a me ka hoʻohana haʻahaʻa o ka ikehu. Eia nō naʻe, loaʻa iā ia nā palena no ka hana ʻenehana, ma muli o ka pono o nā ipu kuʻi paʻi i hoʻolālā kūikawā ʻia. ʻO ka Coprecipitation, ma ka ʻaoʻao ʻē aʻe, e alakaʻi ʻia i kahi ʻōnaehana hoʻonā, kahi i hoʻopili ʻia ai ka morphology precursor e nā ʻano like ʻole e like me ka neʻe ʻana, ka mālama ʻana i ka mahana, ka hoʻoponopono pH, a me ka hoʻoulu ʻana. Hāʻawi ʻia i ke kuleana koʻikoʻi o kēia mau ʻāpana i ka hana ʻana o ka mea LiFePO sintered hope loa, he mea koʻikoʻi ke koho akahele o nā kūlana hoʻokolohua. ʻO nā huahana i hoʻomākaukau ʻia e kēia ʻano ʻaʻole wale nā hiʻohiʻona microstructure maikaʻi loa (ʻo ia hoʻi, ka liʻiliʻi liʻiliʻi a me ke ʻano like ʻole) akā hōʻike pū kekahi i nā waiwai electrochemical maikaʻi; akā naʻe, pono e hoʻomaopopo ʻia he paʻakikī ke kaʻina hana holoʻokoʻa, a hiki mai nā pilikia kānana a me nā pilikia hoʻokele ʻōpala i ka wā e hana ai.
Lithium manganese oxide a me lithium-waiwai manganese-mea waiwai cathode
Lithium manganese oxide
Ma ka noiʻi ʻana o ka lithium -ion battery cathode material, ʻo kekahi mea koʻikoʻi a loaʻa ma ke kūʻai aku ʻana, ʻo ia ka spinel-structured lithium manganese oxide (LiMn₂O₄) cathode material i manaʻo ʻia e Thackeray et al. i ka makahiki 1983. ʻO Spinel-i kūkulu ʻia ka lithium manganese oxide no ka ʻōnaehana kristal cubic. ʻO LiMn₂O₄ kona hui kemika maʻamau. I loko o ka hale aniani LiMn₂O₄, aia ka oxygen i loko o ka hale -concent cubic close-packed structure, aʻo ka manganese a me ka oxygen e hana i ka octahedral structure, e like me ka mea i hōʻike ʻia ma ke kiʻi ma lalo nei.
He nui ka manganese ma ke ʻano, a ʻo nā ʻano hana hoʻomākaukau no ke ʻano litiumu manganese oxide (LiMn2O4) ʻano spinel ʻano like ʻole. ʻO ke ala synthesis a me ka ʻenehana hana o ka mea pili pono i ka microstructure a me ka hoʻomohala ʻana i ka palaoa o ka huahana hope. No laila, he mea koʻikoʻi ka hoʻomaikaʻi ʻana i kēia mau kaʻina synthesis no ka hoʻomaikaʻi ʻana i ka hana electrochemical o nā mea electrode i nā noi kūpono. I kēia manawa, hoʻohana nui ka ʻoihana a me ka ʻoihana kula i ʻelua ʻano hana nui e hoʻomākaukau ai i ka LiMn2O4: ʻo kekahi e pili ana i ka pilina ma waena o nā mea maka paʻa, e like me ke kiʻekiʻe -wela paʻa paʻa-state reactions, microwave-assisted synthesis, and impregnation treatment in molten paʻakai.
ʻO kekahi māhele ʻē aʻe e pili ana i ka hoʻololi kemika i loko o kahi kaiapuni wai, me nā laʻana maʻamau e like me ka ʻenehana sol-gel, hydrothermal synthesis, a me nā ʻenehana corecipitation. Ua ʻike nui ʻia ʻo LiMnzO4 ma muli o ke kumukūʻai, ke kūpaʻa wela maikaʻi loa, ke kūpaʻa overcharge ikaika, a me nā pono kūlohelohe maikaʻi. Eia nō naʻe, he mau hemahema kēia mea i ka hana kaʻa kaʻa a me ka mālama ʻana, ʻoi aku ka nui ma nā wela kiʻekiʻe, kahi e hōʻemi nui ai kāna hana kaʻa, e alakaʻi ana i ka nalowale o ka hiki ʻole.
ma muli o -manane -waiwai lithium
Ma waho aʻe o ka lithium manganese oxide, ua hoʻokipa nui ʻia nā mea i hoʻopaʻa ʻia i ka lithium -manene -waiwai i hoʻopaʻa ʻia ma ke ʻano he mea cathode e puka mai ana no nā ʻōhua lithium-ion.
ʻO nā ʻano hana hoʻomākaukau no ka lithium-rich manganese-based cathode metals, he paʻa-meana, sol-gel, a me-coupitation. ʻO ke ʻano paʻa -ʻano hana e hui pono ai i nā ʻokikene metala a me nā carbonate metala a i ʻole ka metala hydroxides i kekahi ʻāpana, a ukali ʻia e ka -mahana paʻa paʻa-kiʻekiʻe no ka loaʻa ʻana o nā mea waiwai lithium{9}}papa. ʻO nā mea maikaʻi o ke ʻano paʻa{11}}ʻo ia kona hiki ke hoʻohui i nā mea waiwai nui lithium{12}}papa, kona ʻano hoʻomākaukau maʻalahi, a me kona kumu kūʻai haʻahaʻa. ʻO ka hemahema, ʻo ia ka heluna diffusion maikaʻi ʻole o ka paʻa i ka wā paʻa -state sintering, a me ka ʻoiaʻiʻo o nā metala hoʻololi ʻokoʻa ka nui o ka hoʻopuehu ʻokoʻa i loko o ka -ʻano hoʻohenehene paʻa, e paʻakikī ai i nā ʻāpana ke hoʻopuehu lawa. No laila, ʻilihune ka like ʻole o ka mea synthesized, e pili ana i ka hana o ka mea cathode. ʻO ke ʻano sol{18}}gel ka hoʻohui mua ʻana i ka wai paʻakai hoʻololi i ka mea hoʻohui e hana i sol, a laila e hoʻoheheʻe ʻia ka wai e lilo ia i gel, a hope hoʻi e hoʻomaloʻo a calcining no ka loaʻa ʻana o nā mea waiwai lithium{19}}papa. Hāʻawi kēia ʻano i nā mea me ka hāʻawi like ʻana a me ka maʻemaʻe kiʻekiʻe, a ʻo nā electrodes i hana ʻia e hōʻike i ka hana electrochemical maikaʻi. Eia nō naʻe, ʻo kāna mau drawbacks kahi pōʻai hana lōʻihi, ka pono o nā mea hoʻohui he nui (organic acids a i ʻole ethylene glycol), ka hopena i nā kumukūʻai kiʻekiʻe. Eia kekahi, ʻo nā mea waiwai lithium -papa i hana ʻia he mau ʻāpana nano/micron maikaʻi me ka haʻahaʻa haʻahaʻa maoli. No laila, hoʻohana mua ʻia kēia ʻano hana i nā hoʻonohonoho hoʻokolohua no ka hana ʻana i nā mea waiwai lithium -papa a paʻakikī ke kūʻai aku.
Mea kiʻekiʻe-nickel cathode
Ua ʻimi lōʻihi ka poʻe noiʻi i ka paʻa kiʻekiʻe -mehana a me ka hoʻokō helu maikaʻi loa ma ke ʻano he pahuhopu mua i ka wā e kūkulu ana i ka cathode.
nā mea no nā pākahi lithium-ion. Ma waena o nā mea nui ʻekolu - LiCoO₂, LiNi₁ₓ₋ᵧCo₁ₓ₋ᵧCoₓMnᵧO₂ (NCM), a me LiFePO₄ - NCM i manaʻo ʻia kekahi o nā mea cathode maikaʻi loa ma muli o kona hiki ke kiʻekiʻe kiʻekiʻe, haʻahaʻa haʻahaʻa kumu kumu kūʻai, ʻoi aku ka palekana ma mua o ka LiCoO maikaʻi a me ka maikaʻi o ke kaiapuni.
He ʻano like ka -NaFeO₂-ano like o kēia ʻano mea a no ka R-3m hui ākea. Ua manaʻo mua ʻia kēia manaʻo e Liu et al. i 1999. Hoʻohui akamai ia i nā pono o nā mea cathode ʻekolu - lithium cobalt oxide (LiCoO₂), lithium nickel oxide (LiNiO₂), a me lithium manganese oxide (LiMnO₂) - a hoʻopaʻi maikaʻi i nā hemahema i loaʻa i kēlā me kēia mea (e like me ka hōʻike ʻana ma ke Kiʻi 5-6). Ma ka hoʻoponopono ʻana i ka lakio o nā mea metala hoʻololi, hiki ke hoʻokō hou ʻia ke kaulike maikaʻi loa ma waena o ka mana kikoʻī, ka hana pōʻai, palekana, a me ke kumukūʻai.
ʻO ke ʻano aniani o ka lithium nickel cobalt manganese oxide (NCM) ternary cathode material he mea like ia me ka LiCoO2, ʻo ia nā mea ʻelua i ke ʻano hexagonal layered.
