Txoj kev tshawb fawb tau tshawb pom ib txoj hauv kev ua cov roj teeb uas peb siv txhua hnub kom muaj zog dua, muaj zog thiab nyab xeeb.
Xyoo 2018 yog xyoo uas peb lub neej niaj hnub no siv ntau yam khoom siv hluav taws xob los yog roj teeb. Peb txoj kev vam khom rau cov khoom siv hluav taws xob thiab cov khoom siv hluav taws xob tab tom loj hlob zoo kawg nkaus. Lub roj teeb yog ib lub cuab yeej uas khaws cov zog tshuaj uas hloov mus ua hluav taws xob. Cov roj teeb zoo li cov tshuaj me me uas muaj cov tshuaj tiv thaiv uas tsim cov hluav taws xob puv nrog lub zog uas ntws los ntawm lub cuab yeej sab nraud. Txawm hais tias nws yog lub xov tooj ntawm tes lossis laptops lossis lwm lub tsheb fais fab, cov roj teeb - feem ntau yog lithium-ion - yog lub zog tseem ceeb rau cov thev naus laus zis no. Raws li thev naus laus zis txuas ntxiv mus, muaj kev thov tas mus li rau cov roj teeb me me, muaj peev xwm siab, thiab muaj kev nyab xeeb.
Cov roj teeb muaj keeb kwm ntev thiab muaj koob meej. Tus kws tshawb fawb Asmeskas Benjamin Franklin thawj zaug siv lo lus "roj teeb" hauv xyoo 1749 thaum ua kev sim nrog hluav taws xob siv cov txheej txheem txuas txuas. Italian physicist Alessandro Volta tau tsim thawj lub roj teeb nyob rau hauv 1800 thaum hestacked discs ntawm tooj liab (Cu) thiab zinc (Zn) sib cais los ntawm daim ntaub soaked nyob rau hauv dej ntsev. Lub roj teeb txhuas-acid, ib lub roj teeb uas muaj zog tshaj plaws thiab qub tshaj plaws tau tsim nyob rau xyoo 1859 thiab tseem siv ntau yam khoom siv txawm tias niaj hnub no suav nrog lub tshuab hluav taws xob sab hauv hauv tsheb.
Cov roj teeb tau los ntev heev thiab niaj hnub no lawv muaj ntau qhov ntau thiab tsawg los ntawm Megawatt loj, yog li ntawd hauv kev xav lawv muaj peev xwm khaws lub zog los ntawm cov chaw ua liaj ua teb hnub ci thiab teeb pom kev zoo rau cov nroog me me lossis lawv tuaj yeem me npaum li cov uas siv hauv cov moos hluav taws xob, zoo kawg nkaus puas yog. Hauv qhov hu ua lub roj teeb thawj zaug, cov tshuaj tiv thaiv uas tsim cov hluav taws xob ntws tsis tuaj yeem rov qab tau thiab thaum kawg thaum ib qho ntawm nws cov tshuaj tiv thaiv raug siv lub roj teeb yuav tiaj tus lossis tuag. Lub roj teeb thawj zaug feem ntau yog lub roj teeb zinc-carbon. Cov roj teeb thawj zaug no yog teeb meem loj thiab tib txoj hauv kev los daws qhov kev pov tseg ntawm cov roj teeb zoo li no yog nrhiav txoj hauv kev uas lawv tuaj yeem siv dua - uas txhais tau tias los ntawm kev ua rau lawv rov them tau. Kev hloov cov roj teeb nrog ib qho tshiab yog qhov tsis yooj yim sua thiab yog li thaum cov roj teeb tau muaj zog dua thiab loj dua nws tau dhau los ua qhov tsis yooj yim sua tsis hais txog kim heev los hloov lawv thiab pov tseg lawv.
Nickel-cadmium roj teeb (NiCd) yog thawj lub roj teeb uas nrov tshaj plaws uas siv cov alkali ua electrolyte. Xyoo 1989 nickel-hlau hydrogen roj teeb (NiMH) tau tsim muaj lub neej ntev dua li NiCd roj teeb. Txawm li cas los xij, lawv muaj qee qhov tsis zoo, feem ntau yog tias lawv tau hnov ntxhiab heev rau overcharging thiab overheating tshwj xeeb tshaj yog thaum lawv raug them hais rau lawv qhov siab tshaj plaws. Yog li ntawd, lawv yuav tsum tau them nyiaj maj mam thiab ua tib zoo kom tsis txhob muaj kev puas tsuaj thiab yuav tsum tau siv sij hawm ntev dua kom tau them los ntawm cov chargers yooj yim dua.
Tsim tawm xyoo 1980, cov roj teeb Lithium-ion (LIBs) yog cov roj teeb uas siv ntau tshaj plaws hauv cov khoom siv hluav taws xob niaj hnub no. Lithium yog ib qho ntawm cov khoom sib dua tshaj plaws thiab nws muaj ib qho ntawm cov peev xwm hluav taws xob loj tshaj plaws, yog li ntawd qhov kev sib xyaw ua ke no zoo tagnrho rau kev ua cov roj teeb. Hauv LIBs, lithium ions txav mus los ntawm cov electrodes sib txawv los ntawm cov electrolyte uas yog ua los ntawm ntsev thiab cov kuab tshuaj organic (hauv feem ntau LIBs ib txwm muaj). Hauv kev xav, lithium hlau yog cov hlau hluav taws xob zoo tshaj plaws uas muaj peev xwm siab heev thiab yog qhov kev xaiv zoo tshaj plaws rau cov roj teeb. Thaum LIBs tsis tau them rov qab, cov lithium ion uas them rov qab zoo dhau los ua lithium hlau. Yog li, LIBs yog cov roj teeb rechargeable nrov tshaj plaws rau kev siv hauv txhua yam khoom siv portable vim lawv lub neej ntev thiab muaj peev xwm siab. Txawm li cas los xij, ib qho teeb meem loj yog tias cov electrolyte tuaj yeem ua pa tau yooj yim, ua rau luv luv hauv lub roj teeb thiab qhov no tuaj yeem ua rau muaj kev phom sij hluav taws. Hauv kev xyaum, LIBs yeej tsis ruaj khov thiab tsis ua haujlwm zoo vim tias lub sijhawm dhau mus, cov khoom siv lithium tsis sib xws. LIBs kuj muaj cov nqi them thiab tso tawm tsawg thiab kev txhawj xeeb txog kev nyab xeeb ua rau lawv tsis muaj zog rau ntau lub tshuab muaj zog thiab muaj peev xwm siab, piv txwv li tsheb fais fab thiab tsheb sib xyaw. LIB tau tshaj tawm tias muaj peev xwm zoo thiab khaws cia rau qee lub sijhawm tsawg heev.
Yog li, txhua yam tsis zoo tag nrho hauv lub ntiaj teb cov roj teeb raws li nyob rau xyoo tas los no ntau lub roj teeb tau raug cim tias tsis muaj kev nyab xeeb vim tias lawv ntes hluav taws, tsis muaj kev ntseeg siab thiab qee zaum tsis muaj txiaj ntsig. Cov kws tshawb fawb thoob ntiaj teb tab tom nrhiav kev tsim cov roj teeb uas yuav me me, muaj kev nyab xeeb rov qab, sib dua, muaj zog dua thiab nyob rau tib lub sijhawm muaj zog dua. Yog li ntawd, lub hom phiaj tau hloov mus rau cov khoom siv hluav taws xob hauv lub xeev uas muaj peev xwm hloov tau. Khaws qhov no raws li lub hom phiaj ntau txoj kev xaiv tau raug sim los ntawm cov kws tshawb fawb, tab sis kev ruaj ntseg thiab kev ua kom muaj zog tau ua ib qho teeb meem ntawm feem ntau ntawm cov kev tshawb fawb. Polymer electrolytes tau pom muaj peev xwm loj vim tias lawv tsis tsuas yog ruaj khov tab sis kuj hloov tau thiab pheej yig. Hmoov tsis zoo, qhov teeb meem tseem ceeb nrog xws li polymer electrolytes yog lawv cov conductivity tsis zoo thiab txhua yam khoom.
Nyob rau hauv kev tshawb fawb tsis ntev los no luam tawm hauv ACS Nano Letters , cov kws tshawb fawb tau qhia tias lub roj teeb txoj kev nyab xeeb thiab txawm tias ntau lwm yam khoom tuaj yeem txhim kho los ntawm kev ntxiv nanowires rau nws, ua rau lub roj teeb zoo dua. Pab pawg neeg tshawb fawb no los ntawm College of Materials Science thiab Engineering, Zhejiang University of Technology, Tuam Tshoj tau tsim los ntawm lawv txoj kev tshawb fawb yav dhau los uas lawv tau ua magnesium borate nanowires uas tau ua kom pom cov khoom siv kho tshuab zoo thiab conductivity. Hauv kev tshawb fawb tam sim no lawv tau kuaj xyuas seb qhov no puas yuav muaj tseeb rau cov roj teeb thaum cov nanowires no raug ntxiv rau hauv cov khoom siv polymer electrolyte. Cov khoom siv electrolyte tau sib xyaw nrog 5, 10, 15 thiab 20 qhov hnyav ntawm magnesium borate nanowires. Nws tau pom tias cov nanowires ua rau cov conductivity ntawm cov khoom siv polymer electrolyte uas ua rau cov roj teeb muaj zog thiab resilient dua thaum piv rau yav dhau los tsis muaj nanowires. Qhov kev nce ntxiv ntawm conductivity yog vim muaj kev nce ntxiv ntawm cov ions hla thiab txav mus los ntawm electrolyte thiab ntawm tus nqi sai dua. Tag nrho cov teeb tsa zoo li lub roj teeb tab sis nrog ntxiv nanowires. Qhov no qhia tau tias muaj kev ua tau zoo dua thiab nce lub voj voog piv rau cov roj teeb ib txwm muaj. Ib qho kev sim tseem ceeb ntawm kev kub hnyiab kuj tau ua tiav thiab pom tias lub roj teeb tsis kub hnyiab. Cov ntawv thov siv dav dav niaj hnub no xws li xov tooj ntawm tes thiab laptops yuav tsum tau hloov kho dua tshiab nrog lub zog khaws cia siab tshaj plaws thiab me me tshaj plaws. Qhov no pom tseeb tias ua rau muaj kev pheej hmoo ntawm kev tso tawm hnyav thiab nws tuaj yeem tswj tau rau cov khoom siv zoo li no vim yog hom roj teeb me me uas xav tau. Tab sis thaum cov ntawv thov roj teeb loj dua tau tsim thiab sim, kev nyab xeeb, kev ruaj khov thiab lub zog yog qhov tseem ceeb tshaj plaws.
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Qhov (s)
Sheng O et al. 2018. Mg2B2O5 Nanowire Enabled Multifunctional Solid-State Electrolytes nrog High Ionic Conductivity, Zoo heev Mechanical Properties, thiab Flame-Retardant Performance. Nano Letters. https://doi.org/10.1021/acs.nanolett.8b00659
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