Lithium-ion mabhatiri ari kunyanya kusimukira munzira yekuwanda kwesimba. Patembiricha yemumba, silicon-based negative electrode materials alloy ine lithium kugadzira lithium-rich product Li3.75Si phase, ine huronyo hunosvika 3572 mAh/g, iyo yakakwira zvakanyanya kudarika theoretical chaiyo kugona kwegraphite negative electrode 372. mAh/g. Nekudaro, panguva yekudzokororwa kuchaja uye kuburitsa maitiro esilicon-based negative electrode zvinhu, iyo chikamu shanduko yeSi neLi3.75Si inogona kuburitsa yakakura vhoriyamu yekuwedzera (inenge 300%), izvo zvinozotungamira mukuumbwa kwehupfu hwemagetsi emagetsi uye kuenderera kuumbwa kwe. SEI firimu, uye pakupedzisira kukonzera kugona kudonha nekukurumidza. Indasitiri inonyanya kunatsiridza mashandiro esilicon-based negative electrode zvinhu uye kugadzikana kwesilicon-based mabhatiri kuburikidza nano-sizing, kabhoni coating, pore kuumbwa uye humwe hunyanzvi.
Carbon zvinhu zvine conductivity yakanaka, mutengo wakaderera, uye nzvimbo dzakafara. Vanogona kuvandudza conductivity uye pamusoro kugadzikana kwesilicon-based zvinhu. Ivo vanosarudzika kushandiswa sekuwedzera kwekuita kwekuwedzera kwesilicon-based negative electrodes. Silicon-kabhoni zvinhu ndiyo huru yekusimudzira kutungamira kwesilicon-based negative electrodes. Carbon coating inogona kuvandudza kugadzikana kwepasi kwesilicon-based zvinhu, asi kugona kwayo kuvharidzira silicon vhoriyamu yekuwedzera ndeyese uye haigone kugadzirisa dambudziko resilicon vhoriyamu yekuwedzera. Nokudaro, kuitira kuti uvandudze kugadzikana kwesilicon-based materials, porous structures inoda kuvakwa. Kugaya bhora inzira yakasimukira yekugadzirira nanomaterials. Zvimwe zvekuwedzera kana zvinhu zvemukati zvinogona kuwedzerwa kune slurry inowanikwa nebhora kugaya zvinoenderana nezvinodiwa zvekugadzira zvezvakasanganiswa zvinhu. Iyo slurry inoparadzirwa zvakaenzana kuburikidza neakasiyana slurries uye sprayed-yakaomeswa. Munguva yekuomesa nekukasira, iyo nanoparticles uye zvimwe zvikamu mu slurry zvinongoerekana zvagadzira porous structural maitiro. Iri bepa rinoshandisa maindasitiri uye ane hushamwari bhora kugaya uye kupfapfaidza kuomesa tekinoroji kugadzirira porous silicon-yakavakirwa zvinhu.
Kuita kwesilicon-based materials kunogonawo kuvandudzwa nekugadzirisa morphology uye kugovera maitiro esilicon nanomaterials. Parizvino, silicon-based materials ine siyana morphologies uye kugovera maitiro akagadzirwa, akadai sesilicon nanorods, porous graphite embedded nanosilicon, nanosilicon yakagoverwa mu carbon spheres, silicon / graphene array porous structures, nezvimwewo. , nanosheets inogona kudzvanya zviri nani dambudziko rekupwanya rinokonzerwa nekuwedzera kwevhoriyamu, uye zvinhu zvacho zvine hunyoro hwepamusoro. Iyo isina kurongeka stacking ye nanosheets inogona zvakare kugadzira porous chimiro. Kubatana nesilicon negative electrode exchange group. Ipa buffer nzvimbo yekuwedzera vhoriyamu yesilicon zvinhu. Iko kuunzwa kwekabhoni nanotubes (CNTs) haingogone kuvandudza mafambisirwo ezvinyorwa, asi zvakare kukurudzira kuumbwa kweporous zvimiro zvechinyorwa nekuda kweiyo-dimensional morphological maitiro. Iko hakuna mishumo pane porous zvimiro zvakavakwa nesilicon nanosheets uye CNTs. Iri bepa rinotora maindasitiri anoshanda bhora kugaya, kukuya uye kuparadzira, kupfapfaidza kuomeswa, kabhoni pre-coating uye calcination nzira, uye rinounza porous vanosimudzira mugadziriro yekugadzirira kugadzirira porous silicon-based negative electrode zvinhu zvinoumbwa nekuzvibatanidza kwesilicon nanosheets uye. CNTs. Maitiro ekugadzirira ari nyore, ane hushamwari kwezvakatipoteredza, uye hapana tsvina yemvura kana tsvina inosara inogadzirwa. Kune akawanda zvinyorwa zvinyorwa pamusoro pekabhoni coating yesilicon-based materials, asi kune mashoma-yakadzama nhaurirano pamusoro pemhedzisiro yekupfeka. Iri bepa rinoshandisa asphalt seyo kabhoni sosi yekuongorora magadzirirwo emhando mbiri dzekupotera kabhoni, yemvura chikamu chekuputira uye yakasimba chikamu chekupotera, pane coating maitiro uye mashandiro esilicon-based negative electrode zvinhu.
1 Kuedza
1.1 Kugadzirira kwezvinhu
Kugadzirira kweporous silicon-kabhoni composite zvinhu zvinonyanya zvinosanganisira matanho mashanu: bhora kugaya, kugaya uye kupararira, pfapfaidzo kuomesa, kabhoni pre-coating uye carbonization. Chekutanga, kuyera 500 g yekutanga silicon powder (yemumba, 99.99% kuchena), wedzera 2000 g ye isopropanol, uye ita bhora rakanyorova kukuya pabhora rekugaya kumhanya kwe2000 r/min kwemaawa makumi maviri nemana kuti uwane nano-scale silicon slurry. Iyo yakawanikwa silicon slurry inoendeswa kune tangi yekuparadzira, uye zvinhu zvinowedzerwa zvinoenderana nehuwandu hwehuwandu hwesilicon: graphite (inogadzirwa muShanghai, bhatiri giredhi): carbon nanotubes (inogadzirwa muTianjin, bhatiri giredhi): polyvinyl pyrrolidone (yakagadzirwa. muTianjin, analytical giredhi) = 40:60:1.5:2. Isopropanol inoshandiswa kugadzirisa zvinhu zvakasimba, uye zvinyorwa zvakasimba zvakagadzirirwa kuva 15%. Kukuya uye kupararira kunoitwa pakupararira kumhanya kwe3500 r / min kwe4 h. Rimwe boka re slurries pasina kuwedzera CNTs rinofananidzwa, uye zvimwe zvinhu zvakafanana. Iyo yakawanikwa yakaparadzirwa slurry inozoendeswa kune yekupfapfaidza yekudyisa tangi, uye kupfapfaidza kuomeswa kunoitwa mumhepo ine nitrogen-yakachengetedzwa, neinopinza uye yekubuda tembiricha iri 180 uye 90 ° C, zvichiteerana. Ipapo marudzi maviri ekuputira kabhoni akaenzaniswa, yakasimba phase coating uye liquid phase coating. Iyo yakasimba chikamu chekuputira nzira ndeye: iyo spray-yakaomeswa poda inosanganiswa ne20% asphalt poda (yakagadzirwa muKorea, D50 iri 5 μm), yakasanganiswa mumuchina musanganisi kwemaminetsi gumi, uye kumhanya kwekusanganisa i2000 r/min kuwana. pre-coated powder. Iyo yemvura chikamu chekuputira nzira ndeye: iyo yakapfapfaidzwa-yakaomeswa poda inowedzerwa kune xylene mhinduro (yakagadzirwa muTianjin, analytical giredhi) ine 20% asphalt yakanyungudutswa muhupfu pane yakasimba ye55%, uye vacuum yakamutswa zvakaenzana. Bika muchoto chevacuum pa85 ℃ ye4h, isa mu mechanical mixer yekuvhenganisa, kukurumidza kusanganiswa ndeye 2000 r / min, uye nguva yekusanganiswa ndeye 10 min kuti uwane pre-yakaputirwa poda. Pakupedzisira, poda yakagara yakavharwa yakakonzerwa mumoto unotenderera pasi pemhepo ye nitrogen pakupisa kwe5 ° C / min. Yakatanga kuchengetwa patembiricha isingaperi ye550 ° C kwe2h, ndokuzoenderera mberi ichipisa kusvika 800 ° C uye ichichengetwa patembiricha yenguva dzose kwe2h, uyezve yakatonhodzwa kusvika pasi pe100 ° C uye yakaburitswa kuti iwane silicon-carbon. composite zvinhu.
1.2 Maitiro ekuita maitiro
Iyo particle saizi yekugoverwa kwezvinhu yakaongororwa uchishandisa particle size tester (Mastersizer 2000 shanduro, yakagadzirwa kuUK). Hupfu hwakawanikwa munhanho imwe neimwe yakaedzwa nekuongorora electron microscopy (Regulus8220, yakagadzirwa muJapan) kuongorora morphology uye kukura kwehupfu. Chimiro chechikamu chechinyorwa chakaongororwa pachishandiswa X-ray poda diffraction analyzer (D8 ADVANCE, yakagadzirwa kuGermany), uye kuumbwa kwekutanga kwechinyorwa kwakaongororwa uchishandisa simba spectrum analyzer. Iyo yakawanikwa silicon-kabhoni composite zvinhu yakashandiswa kugadzira bhatani hafu-sero yemuenzaniso CR2032, uye huwandu hwehuwandu hwesilicon-kabhoni: SP: CNT: CMC: SBR yaive 92: 2: 2: 1.5: 2.5. Iyo counter electrode isimbi lithium sheet, iyo electrolyte inotengesa electrolyte (modhi 1901, yakagadzirwa muKorea), Celgard 2320 diaphragm inoshandiswa, charge uye discharge voltage renji i0.005-1.5 V, kuchaja uye kuburitsa ikozvino 0.1 C. (1C = 1A), uye iyo yekubvisa-yekubvisa-yezvino ndeye 0.05 C.
Kuti uwedzere kuongorora kushanda kwesilicon-carbon composite zvinhu, laminated diki nyoro-pack bhatiri 408595 yakagadzirwa. Iyo yakanaka electrode inoshandisa NCM811 (yakagadzirwa muHunan, bhatiri giredhi), uye iyo negative electrode graphite inogadzirwa ne8% silicon-carbon material. Iyo yakanaka electrode slurry formula ndeye 96% NCM811, 1.2% polyvinylidene fluoride (PVDF), 2% conductive agent SP, 0.8% CNT, uye NMP inoshandiswa se dispersant; iyo negative electrode slurry formula ndeye 96% composite negative electrode material, 1.3% CMC, 1.5% SBR 1.2% CNT, uye mvura inoshandiswa se dispersant. Mushure mekubvongodza, kupeta, kutenderedza, kucheka, lamination, tab welding, kurongedza, kubika, jekiseni remvura, kuumbwa uye kupatsanura simba, 408595 laminated diki nyoro pack mabhatiri ane yakayerwa kugona kwe3 Ah akagadzirwa. Chiyero chekuita kwe0.2C, 0.5C, 1C, 2C uye 3C uye kutenderera kwekuita kwe0.5C kubhadharisa uye 1C kubuda kwakaedzwa. Kuchajisa uye kuburitsa voltage renji yaive 2.8-4.2 V, inogara iripo uye inogara ichichaja voltage, uye iyo yekucheka-kubvisa ikozvino yaive 0.5C.
2 Migumisiro uye Kukurukurirana
Iyo yekutanga silicon poda yakaonekwa nekuongorora electron microscopy (SEM). Iyo silicon poda yaive isina kurongeka granular ine particle size isingasviki 2μm, sezvakaratidzwa muFigure 1(a). Mushure mekugaya bhora, ukuru hwesilicon powder hwakaderedzwa kusvika pa100 nm [Mufananidzo 1 (b)]. Iyo particle size test yakaratidza kuti iyo D50 yesilicon poda mushure mekugaya bhora yaive 110 nm uye iyo D90 yaive 175 nm. Kunyatsoongorora morphology yesilicon powder mushure mekucheka kwebhora kunoratidza chimiro chisina kujeka (kuumbwa kwechimiro chechimiro chinoputika chichave chichisimbiswa kubva kune-sectional SEM gare gare). Naizvozvo, iyo D90 data yakawanikwa kubva muyedzo saizi yechikamu inofanira kunge iri kureba kweye nanosheet. Yakasanganiswa nemigumisiro yeSEM, inogona kutongwa kuti ukuru hwenanosheet yakawanikwa idiki pane yakakosha kukosha kwe150 nm yekuputsika kwesilicon powder panguva yekuchaja uye kuburitsa mune inokwana dimension imwe. Kugadzirwa kweiyo flaky morphology kunonyanya kukonzerwa nekusiyana kwesimba rekuparadzanisa kwekristaro ndege dzecrystalline silicon, pakati peiyo {111} ndege yesilicon ine yakaderera dissociation simba pane {100} uye {110} crystal ndege. Naizvozvo, iyi ndege yekristaro iri nyore kutetepa nekugaya bhora, uye pakupedzisira inoumba chimiro chisina kujeka. Iyo isina kuchena chimiro inokodzera kuunganidzwa kwezvimiro zvakasununguka, inochengetera nzvimbo yekuwedzera vhoriyamu yesilicon, uye inovandudza kugadzikana kwezvinhu.
Iyo slurry ine nano-silicon, CNT uye graphite yakapfapfaidzwa, uye poda isati yasvika uye mushure mekupfapfaidza yakaongororwa neSEM. Mhedzisiro inoratidzwa muMufananidzo 2. Iyo graphite matrix yakawedzerwa isati yapfapfaidza inofananidzira flake chimiro nehukuru hwe5 kusvika 20 μm [Mufananidzo 2 (a)]. Iyo particle size yekugovera bvunzo yegraphite inoratidza kuti D50 ndeye 15μm. Iyo hupfu inowanikwa mushure mekupfapfaidza ine spherical morphology [Mufananidzo 2 (b)], uye inogona kuonekwa kuti girafu yakaputirwa nemucheka wekuputira mushure mekupfapfaidza. Iyo D50 yehupfu mushure mekupfapfaidza ndeye 26.2 μm. Iyo morphological maitiro ezvikamu zvechipiri zvakaonekwa neSEM, zvichiratidza maitiro ehutsika hwakasununguka hunounganidzwa nemananomaterials [Mufananidzo 2 (c)]. Iyo porous dhizaini inoumbwa nesilicon nanosheets uye CNTs dzakarukwa neimwe [Mufananidzo 2(d)], uye bvunzo chaiyo nzvimbo (BET) yakakwira se53.3 m2/g. Naizvozvo, mushure mekupfapfaidza, silicon nanosheets uye CNTs inozviunganidza kuti iite porous chimiro.
Iyo porous layer yakabatwa neyemvura kabhoni coating, uye mushure mekuwedzera kabhoni coating precursor pitch uye carbonization, kucherechedzwa kweSEM kwakaitwa. Zvigumisiro zvinoratidzwa muMufananidzo 3. Mushure mokunge carbon pre-coating, nzvimbo yezvikamu zvechipiri inova yakanyorova, ine jira rakajeka rekuputira, uye kuvhara kwapera, sezvinoratidzwa muMifananidzo 3 (a) uye (b). Mushure mekuita carbonization, iyo yepamusoro yekuputira layer inochengetedza yakanaka yekuvhara mamiriro [Mufananidzo 3 (c)]. Mukuwedzera, mufananidzo weSEM-sectional unoratidza mitsetse-yakaumbwa nanoparticles [Mufananidzo 3 (d)], iyo inofananidzwa nemaitiro e-morphological e nanosheets, inowedzera kusimbisa kuumbwa kwesilicon nanosheets mushure mekugadzira bhora. Mukuwedzera, Mufananidzo 3 (d) unoratidza kuti kune mafirita pakati pemamwe nanosheets. Izvi zvinonyanya kukonzerwa nekushandiswa kweiyo liquid phase coating method. Iyo asphalt mhinduro ichapinda mukati mezvinyorwa, kuitira kuti pamusoro peiyo mukati silicon nanosheets iwane kabhoni coating inodzivirira layer. Naizvozvo, nekushandisa fluid chikamu coating, mukuwedzera pakuwana iyo yechipiri particle coating effect, iyo yakapetwa kabhoni yekuvhara mhedzisiro yeprimary particle coating inogonawo kuwanikwa. Iyo carbonized powder yakaedzwa neBET, uye mhinduro yekuedza yaiva 22.3 m2 / g.
Iyo carbonized powder yakaiswa pasi pe-cross-sectional energy spectrum analysis (EDS), uye zvigumisiro zvinoratidzwa mumufananidzo 4 (a). Iyo micron-saizi musimboti iC chikamu, inoenderana neiyo graphite matrix, uye iyo yekunze yekupfeka ine silicon uye oksijeni. Kuti uwedzere kuongorora chimiro chesilicon, bvunzo yeX-ray diffraction (XRD) yakaitwa, uye mhedzisiro inoratidzwa muMufananidzo 4 (b). Izvo zvinyorwa zvinonyanya kuumbwa negraphite uye imwe-crystal silicon, isina pachena silicon oxide maitiro, zvichiratidza kuti iyo okisijeni chikamu cheiyo simba spectrum bvunzo inonyanya kuuya kubva kune yakasikwa oxidation yesilicon pamusoro. Iyo silicon-carbon composite zvinhu yakanyorwa seS1.
Iyo yakagadzirirwa silicon-kabhoni zvinhu S1 yakaiswa pasi pebhatani-mhando hafu-sero kugadzirwa uye yekuchaja-kuburitsa bvunzo. Yekutanga yekuchaja-kuburitsa curve inoratidzwa muFigure 5. Iyo inodzoreredzwa yakananga chiyero ndeye 1000.8 mAh / g, uye yekutanga kutenderera inoshanda yakakwira se93.9%, iyo yakakwirira kupfuura yekutanga kushanda kweakawanda silicon-based zvinhu pasina pre- lithiation yakataurwa mumabhuku. Iyo yepamusoro yekutanga kushanda zvakanaka inoratidza kuti yakagadzirwa silicon-carbon composite material ine yakanyanya kugadzikana. Kuti uone mhedzisiro ye porous chimiro, conductive network uye kabhoni coating pane kugadzikana kwesilicon-kabhoni zvinhu, mhando mbiri dzesilicon-kabhoni zvinhu zvakagadzirirwa pasina kuwedzera CNT uye pasina yekutanga kabhoni coating.
Iyo morphology ye carbonized powder yesilicon-carbon composite zvinhu pasina kuwedzera CNT inoratidzwa muMufananidzo 6. Mushure mekuvhara kwechikamu chemvura uye carbonization, jira rinoputika rinogona kuonekwa zvakajeka pamusoro pezvikamu zvechipiri mumufananidzo 6 (a). Muchinjikwa-sectional SEM weiyo carbonized zvinhu inoratidzwa muMufananidzo 6 (b). Kuiswa kwesilicon nanosheets kune porous hunhu, uye BET bvunzo ndeye 16.6 m2/g. Zvisinei, kana ichienzaniswa nemhosva neCNT [sezvinoratidzwa muMufananidzo 3 (d), BET bvunzo yehupfu hwayo hwekabhoni ndeye 22.3 m2 / g], mukati nano-silicon stacking density yakakwirira, zvichiratidza kuti kuwedzerwa kweCNT kunogona kukurudzira. kuumbwa kwechimiro cheporous. Mukuwedzera, zvinyorwa hazvina matatu-dimensional conductive network yakagadzirwa neCNT. Iyo silicon-carbon composite zvinhu yakanyorwa seS2.
Maitiro e-morphological of the silicon-carbon composite material yakagadzirirwa ne-soli-phase carbon coating inoratidzwa muMufananidzo 7. Mushure me carbonization, pane jira rakajeka rekuvhara pamusoro, sezvinoratidzwa mumufananidzo 7 (a). Mufananidzo 7 (b) unoratidza kuti kune mitsetse-yakaumbwa nanoparticles muchikamu chemuchinjikwa, iyo inoenderana nemaitiro e-morphological e nanosheets. Kuunganidzwa kwe nanosheets kunoumba porous chimiro. Iko hakuna kuzadza kuri pachena pamusoro peiyo nanosheets yemukati, zvichiratidza kuti iyo yakasimba-phase kabhoni coating inongogadzira kabhoni yekuvhara layer ine porous chimiro, uye hapana yemukati yekupfeka layer yesilicon nanosheets. Iyi silicon-carbon composite zvinhu yakanyorwa seS3.
Iyo bhatani-mhando yehafu-sero kuchaja uye yekuburitsa bvunzo yakaitwa paS2 uye S3. Iyo chaiyo hunyanzvi uye yekutanga kushanda kweS2 yaive 1120.2 mAh / g uye 84.8%, zvichiteerana, uye chaiyo hunyanzvi uye yekutanga kushanda kweS3 yaive 882.5 mAh / g uye 82.9%, zvichiteerana. Iyo chaiyo hunyanzvi uye yekutanga kushanda kweiyo yakasimba-chikamu yakavharwa S3 sampuli yaive yakaderera, zvichiratidza kuti chete kabhoni yekuputira ye porous chimiro chakaitwa, uye iyo kabhoni yekupfeka yemukati silicon nanosheets haina kuitwa, iyo isingakwanise kupa zvizere kutamba. kune chaiyo kugona kwesilicon-based material uye yaisagona kuchengetedza pamusoro peiyo silicon-based material. Kushanda kwekutanga kwemuenzaniso weS2 pasina CNT kwaivewo kwakaderera pane iyo yesilicon-carbon composite zvinhu zvine CNT, zvichiratidza kuti pahwaro hwehuputi hwakanaka, iyo conductive network uye yakakwirira dhigirii ye porous chimiro inobatsira pakuvandudza. yekuchaja uye kuburitsa kunyatsoita kwesilicon-carbon zvinhu.
Iyo S1 silicon-kabhoni zvinhu yakashandiswa kugadzira diki yakapfava-pack yakazara bhatiri kuti iongorore chiyero chekuita uye kutenderera kuita. Iyo yekuburitsa mwero curve inoratidzwa muMufananidzo 8 (a). Iyo yekuburitsa masimba e0.2C, 0.5C, 1C, 2C uye 3C ndeye 2.970, 2.999, 2.920, 2.176 uye 1.021 Ah, zvichiteerana. Iyo 1C yekuburitsa mwero yakakwira kusvika 98.3%, asi iyo 2C yekuburitsa mwero inodonha kusvika 73.3%, uye iyo 3C yekuburitsa mwero inodonha zvakare kusvika 34.4%. Kuti ubatane nesilicon negative electrode exchange group, ndapota wedzera WeChat: shimobang. Panyaya yekuchaja chiyero, iyo 0.2C, 0.5C, 1C, 2C uye 3C yekuchaja masimba ndeye 3.186, 3.182, 3.081, 2.686 uye 2.289 Ah, zvichiteerana. Iyo 1C yekuchaja chiyero ndeye 96.7%, uye iyo 2C yekuchaja chiyero ichiri kusvika 84.3%. Zvisineyi, tichiona curve yekuchaja muMufananidzo 8(b), 2C yekuchaja chikuva chakakura zvakanyanya pane 1C yekuchaja chikuva, uye inogara ichichaja vhezheni inoverengera vazhinji (55%), zvichiratidza kuti polarization ye2C rechargeable bhatiri. yakatokura zvikuru. Iyo silicon-kabhoni zvinhu ine yakanaka yekuchaja uye yekuburitsa kuita pa1C, asi zvimiro zvemukati zvezvinhu zvinoda kuvandudzwa kuti zviwane chiyero chepamusoro. Sezvinoratidzwa muMufananidzo 9, mushure memazana e450, chiyero chekuchengetedza simba ndeye 78%, ichiratidza kushanda kwakanaka kwekutenderera.
Nzvimbo yepamusoro ye electrode isati yasvika uye shure kwekutenderera kwakaongororwa neSEM, uye zvigumisiro zvinoratidzwa muMufananidzo 10. Pamberi pekutenderera, pamusoro pe graphite uye silicon-carbon zvinhu zvakajeka [Mufananidzo 10 (a)]; mushure mekutenderera, chivharo chekuputira chiri pachena chinogadzirwa pamusoro pepamusoro [Mufananidzo 10 (b)], iyo iri gobvu SEI firimu. SEI firimu roughnessIyo inoshanda lithium kushandiswa kwakakwira, iyo isingaenderane nekuita kutenderera. Naizvozvo, kusimudzira kuumbwa kweiyo yakatsetseka SEI firimu (yakadai seyakagadzirwa SEI firimu rekuvaka, kuwedzera akakodzera electrolyte additives, nezvimwewo) inogona kuvandudza kutenderera kwekuita. Iko kuyambuka-chikamu SEM kucherechedzwa kwesilicon-kabhoni zvimedu mushure mekutenderera [Mufananidzo 10 (c)] inoratidza kuti yekutanga mitsetse-yakaumbwa nesilicon nanoparticles yave yakaoma uye chimiro cheporous chakabviswa. Izvi zvinonyanya kukonzerwa nekuenderera mberi kwevhoriyamu yekuwedzera uye kuputika kwesilicon-carbon zvinhu panguva yekutenderera. Naizvozvo, iyo porous chimiro chinoda kuwedzeredzwa kuti ipe yakakwana buffer nzvimbo yekuwedzera vhoriyamu yesilicon-yakavakirwa zvinhu.
3 Mhedziso
Zvichienderana nekuwedzera kwevhoriyamu, kusaita zvakanaka uye kusagadzikana kwechimiro chesilicon-based negative electrode zvinhu, bepa iri rinoita kuvandudzwa kwakanangwa, kubva pamorphology kuumbwa kwesilicon nanosheets, porous chimiro kuvaka, conductive network kuvaka uye yakazara kabhoni coating yezvikamu zvese zvechipiri. , kuvandudza kugadzikana kwesilicon-based negative electrode zvinhu zvakazara. Iko kuunganidzwa kwesilicon nanosheets kunogona kuumba porous chimiro. Kuunzwa kweCNT kuchawedzera kukurudzira kuumbwa kwechimiro cheporous. Iyo silicon-kabhoni composite zvinhu zvakagadzirirwa neyemvura chikamu coating ine kaviri kabhoni coating mhedzisiro pane iyo yakagadzirwa neyakaomeswa chikamu coating, uye inoratidza yakakwirira chaiyo yakasarudzika uye yekutanga kushanda zvakanaka. Pamusoro pezvo, kushanda kwekutanga kwesilicon-carbon composite material ine CNT yakakwirira kudarika iyo isina CNT, iyo inonyanya kukonzerwa nehupamhi hwepamusoro hweporous structure kukwanisa kuderedza kuwedzera kwehuwandu hwesilicon-based materials. Iko kuiswa kweCNT kuchavaka matatu-dimensional conductive network, kuvandudza conductivity yesilicon-based materials, uye kuratidza chiyero chakanaka chekuita pa1C; uye zvinyorwa zvinoratidza kuita kwakanaka kutenderera. Nekudaro, iyo porous chimiro chechinhu chinoda kusimbiswa zvakare kuti ipe yakakwana buffer nzvimbo yekuwedzera vhoriyamu yesilicon, uye kukurudzira kuumbwa kweyakatsetseka.uye dense SEI firimu kuti iwedzere kuvandudza kutenderera kuita kwesilicon-carbon composite zvinhu.
Isu tinopawo yakakwira-kuchena graphite uye silicon carbide zvigadzirwa, izvo zvinoshandiswa zvakanyanya mukugadzira wafer senge oxidation, diffusion, uye annealing.
Gamuchirai chero vatengi vanobva kumativi ese enyika kuti vatishanyire kune imwezve hurukuro!
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Nguva yekutumira: Nov-13-2024