He aha ka LiFePO4 i loko o nā pākahi lithium??
Hoʻolauna i nā mea waiwai Lithium Iron Phosphate
Lithium iron phosphate (molecular formula LiFePO₄, lithium iron phosphate, LFP, i ʻike ʻia hoʻi me ka lithium iron phosphate a i ʻole ferrous lithium phosphate) he mea cathode i hoʻohana ʻia i loko o nā pākahi lithium{0}}ion. ʻO kona mau hiʻohiʻona ʻaʻole i loaʻa nā mea makamae e like me ka cobalt a i ʻole nickel, haʻahaʻa ke kumu kūʻai kumu; a he nui ka kalapona, lithium, a me ka hao i loko o ka ʻōpala o ka honua, i hiki ke hoʻokō i ka makemake o ka mākeke ma mua o hoʻokahi miliona mau tona i kēlā me kēia makahiki. Ma ke ʻano he cathode, ʻo ka lithium iron phosphate ka uila hana haʻahaʻa (3.2 V), ka mana kikoʻī kiʻekiʻe (170 mA·h/g), ka mana hoʻokuʻu kiʻekiʻe, ka hiki ke hoʻopiʻi wikiwiki, a me ke ola pōʻaiapuni lōʻihi, me ka paʻa maikaʻi i nā ʻāina kiʻekiʻe - wela a kiʻekiʻe - wela.
ʻO ka lithium iron phosphate crystal no kekahi ʻano olivine structure. I ka mineralogy, ua kapa ʻia ʻo ia he triphylite, i loaʻa mai ka huaʻōlelo Helene roots tri a me lylon. I loko o ka ores, hiki ke kala ke hina, ʻulaʻula -ʻeleʻele hina, ʻeleʻele, a ʻeleʻele paha, ʻoiai ʻeleʻele a hina paha{3}}nā huahana maoli. Loaʻa i kekahi mau mea mineral maoli ka lithium iron phosphate, akā haʻahaʻa ka papa a ʻaʻole hiki i ke kiʻekiʻe o ka hoʻohana pono. Lithium hao phosphate no ka composite phosphate waeʻano, a me kona maʻamau kemikala formula LiMPO₄, kahi M hiki i kekahi divalent metala, e like me Fe, Co, Mn, Ti, etc. Eia nō naʻe, no nā pūhui me ke ʻano olivine, ʻaʻole ʻo lithium iron phosphate wale nō ka mea hiki ke hoʻohana ʻia ma ke ʻano he cathode mea i loko o nā pākahi lithium-ion. Wahi a ka ʻike o kēia manawa, aia pū kekahi LiMnPO₄, LiMnFePO₄, LiVPO₄, LiCoPO₄, a me nā mea ʻē aʻe he nui.
Hiki ke huli ʻia ke kumu o nā mea lithium hao phosphate i ka makahiki 1996, i ka wā i ʻike mua ai ka hui kelepona ʻo Iapana ʻo NTT ʻo AMPO₄ (A he metala alkali, M ʻo Co a i ʻole Fe) me ke ʻano olivine, i ka hui ʻana o LiFeCoPO₄, hiki ke hoʻohana ʻia ma ke ʻano he lithium -ion battery cathode material. Ma hope mai, ua ʻike ʻia e ka hui noiʻi ʻo Goodenough ma Massachusetts Institute of Technology ma ʻAmelika Hui Pū ʻIa, ʻoiai e aʻo ana i nā pūhui framework, ua loaʻa i ka mea lithium hao phosphate ka waiwai reversible o ka lithium -ion (Li⁺) intercalation a me ka deintercalation. Ma ʻApelila 23, 1997, ua hoʻopiʻi ke Kulanui o Texas ma Austin i kahi patent i kapa ʻia ʻo "Nā mea Cathode no ka rechargeable lithium secondary batteries" (WO1997010541), e hōʻailona ana i ka hoʻomaka ʻana o ka monopoly patent ma nā mea lithium hao phosphate.
ʻO ka hoʻolaha like ʻana o nā mea cathode olivine-structured phosphate (LiMPO₄) e ʻAmelika Hui Pū ʻIa a me Iapana ua hoihoi nui ʻia ka manaʻo nui, ua hoʻoulu i ka noiʻi nui, a ua holomua wikiwiki i ke kaʻina hana ʻenehana. Hoʻohālikelike ʻia me ka lithium -iona lua o nā ʻano pahu pahu pahu-spinel-i kūkulu ʻia ka lithium manganese oxide (LiMn₂O₄) a me ka papa -i kūkulu ʻia i ka lithium cobalt oxide (LiCoO₂)-LiMPO₄ i loaʻa i ka LiMPO₄ i nā mea hoʻomāhuahua a ʻoi aku ka maikaʻi o ka loaʻa ʻana o nā mea kino kino. ʻO ka mea nui, ua hoʻomaikaʻi maikaʻi ʻia ka palekana, e hoʻāla ana i ka hoihoi nui mai nā mea noiʻi a me nā ʻoihana.
Ma muli o nā hualoa'a noi'i i nā makahiki i hala iho nei, loa'a i ka mea lithium iron phosphate ka -ho'olā'au olivine maika'i, a he 'oko'a kona 'ano litiumu-ion diffusion me ko nā mea cathode kahiko. ʻO nā mea cathode kuʻuna i hoʻopaʻa ʻia a i ʻole nā hale spinel, e ʻae ana i nā ion lithium e neʻe wikiwiki ma waena o nā papa a i ʻole nā kahawai nui, no laila e hāʻawi i nā mea me ka hana hoʻokuʻu maikaʻi. ʻO ka ʻokoʻa, ʻo ka litium -ion diffusion channel i ka lithium iron phosphate material he hoʻokahi-dimensional, ʻo ia hoʻi, aia i loko o ke aniani he "tunnel" wale nō no ka laha ʻana o ka lithium-ion, no laila ua lohi ka neʻe ʻana o ka lithium -ion a he pōkole ka mamao. Ma lalo o nā kūlana ho'oku'u -ki'eki'e, 'a'ole hiki ke ne'e aku nā iona lithium o loko i ka manawa, e hopena i ka polarization electrochemical nui.
Hiki ke hana ʻia nā pila me ka hoʻohana ʻana i ka lithium hao phosphate maʻemaʻe e hōʻoia i nā hopena i luna. Ua hōʻike ʻia nā hoʻokolohua he haʻahaʻa loa ka hoʻohana ʻana o ka lithium iron phosphate maʻemaʻe, a ʻike ka pākaukau i ka pohō wikiwiki ʻana i ka wā kaʻa. Hōʻike ke Kiʻi 2.1 i ka hana kaʻa paikikala o kahi pūnae kālā lithium -ion i hana ʻia e ka mea kākau me ka hydrothermally synthesized lithium iron phosphate maʻemaʻe (me ka ʻole o ka uhi kalapona). Hiki ke ʻike ʻia ma hope o 15 mau kaʻina hoʻoiho-hoʻokuʻu, ua pohō ka mana pākaukau ma mua o 20%. No laila, ʻaʻole kūpono nā mea lithium hao phosphate maʻemaʻe no nā ʻōnaehana pākahi lithium-ion.
I ka makahiki 2000, ʻo Hydro -Québec (H-Q), ka mea hoʻohana lehulehu o Kanada, ka mea mua i waiho i nā palapala hōʻailona no ka uhi ʻana i ka lithium iron phosphate me nā mea conductive, me ka hoʻohana ʻana i ka uhi kalapona ma nā mea hao lithium iron phosphate. ʻO kēia ka mea i hiki ai i ka lithium iron phosphate ke hoʻokō i ka mana kikoʻī kiʻekiʻe a hoʻonui i kona ola pōʻai ma mua o 2000 cycles. Ua hōʻailona kēia i ka hoʻomaka ʻana o ke kaʻina hana ʻoihana o ka lithium iron phosphate ma ke ʻano he cathode material.
