Me yasa Fill Factor ke Bayyana Lalacewar Samar da Tantanin Rana da Farko?

Gabatarwa: Ma'aunin cika ba siga ce ta keɓe ba. Yana tattara juriya ta lamba, leakage, paste formulation, screen printing, harbi, da taga tsarin LECO a cikin I-V curve guda ɗaya.

Inganci Yana Nuna Sakamako, Yayin da FF Yake Bayyana Abin Da Ke Faruwa a Kan Layin Samarwa

Masana'antar photovoltaic ta faɗaɗa cikin sauri a ƙarƙashin canjin makamashi na duniya. Ƙarfin samar da na'urorin photovoltaic na duniya ya riga ya wuce 200 GW, tare da samar da shekara-shekara yana kan sama da 150 GW. A lokaci guda, fasahar PERC ta shiga matakin ƙarshe na rayuwarta. Ƙarfin juyar da samar da yawa ya tashi zuwa 23.5% kuma yana tafiya da wahala zuwa iyakar ka'idar kusan 24%. Ƙarin riba yana daɗa wahala.

Daga mahangar farashin masana'anta, farashin da ba na silicon ba na sel PERC an matse shi zuwa kusan RMB 0.2 a kowace watt, yana barin sarari kaɗan don ƙarin raguwa. Don haka masana'antar ta koma ga fasahohin N-type masu inganci kamar TOPCon, fasahar heterojunction, ko HJT, da sel masu tuntuɓar baya. Manufar ita ce buɗe sabon sararin riba ta hanyar inganci mafi girma da ƙarfin aikin aikin.

Ƙarfin juyar da wuta yana da mahimmanci a fili yayin kimanta tsarar fasahar hasken rana. A kan ainihin layin samar da yawa, duk da haka, ƙarfin buɗe kewayawa, ko Voc, da gajeren kewayawar wutar lantarki, ko Isc, sau da yawa suna daidaita a cikin iyakoki masu kunkuntar. A wannan lokacin, ma'aunin cikawa ya zama alama mai yanke hukunci na ƙarshen samarwa da kuma sigina mai mahimmanci na ƙananan canje-canje na tsari.

A geometri, ma'aunin cika yana auna murabba'in layin halayen I-V na tantanin rana. Shi ne rabo tsakanin ainihin murabba'in iyakar ƙarfi da murabba'in ka'idar da Voc da Isc suka kafa. Ƙimar koyaushe tana ƙasa da 1. A ƙarƙashin yanayi masu kyau, mafi girman FF na tantanin rana na gallium arsenide na iya kusantar 0.89. Iyakar ka'idar ga tantanin rana na siliki na kasuwanci na yau da kullun kusan 0.83 zuwa 0.85.

Layin samarwa ba samfuri mai kyau ba ne. Rashin kyakkyawar hulɗar ƙarfe, zubewar da ke da alaƙa da etching, rashin daidaiton manna, ko taga harbi da aka canza duk na iya dagula hulɗar microscopic. Waɗannan lahani suna da matukar damuwa ga tarin zafi. A ƙarshe suna bayyana a matsayin bambance-bambance masu kaifi a cikin juriya mara kyau kuma galibi ana fallasa su ta hanyar raguwar FF.

Ƙididdiga: Dangantaka Tsakanin Canjin Inganci da FF

η = Pmax / Pin = (Voc × Isc × FF) / Pin

Ma'ana: Lokacin da Voc da Isc suka kasance da kwanciyar hankali, ƙaramin canjin FF yana shiga kai tsaye cikin ingancin canjin ƙarshe.

Ƙididdiga: Ma'anar Ma'aunin Cika

FF = Pmax / (Voc × Isc) = (Vmp × Imp) / (Voc × Isc)

Ma'ana: FF tana auna murabba'in I-V curve. A zahiri, yana nuna yadda tantanin halitta ke canza fitowar wutar lantarki ta ka'ida zuwa ainihin ƙarfin mafi girma.

Jigon Jiki na FF: Jawo Tsakanin Rs da Rsh

Don fahimtar dalilin da yasa FF ke da matukar damuwa ga yanayin masana'anta, dole ne a koma ga samfurin da'irar daidai na tantanin rana. Masu ɗaukar hoto na hasken rana suna tafiya da yaduwa ta jikin siliki kafin a tattara su ta hanyar da'irar waje. Asarar makamashi ba makawa ce a wannan tsari.

A matakin lantarki na macroscopic, waɗannan asarar ana wakilta su ta hanyar juriya mara kyau. Manyan abubuwa biyu sune juriya jerin, Rs, da juriya shunt, Rsh.

Juriya jerin tana wakiltar duk juriya ta gaba da ake fuskanta lokacin da wutar lantarki ke gudana zuwa ga nauyin waje. Sakamakon haɗin juriya na jikin siliki, juriya ta hulɗa tsakanin na'urorin gaba da baya da siliki, juriya ta sufuri ta gefen emitter, juriya ta yatsa da busbar, da kuma, a matakin module, juriya ta ribbon haɗi.

Daga cikin waɗannan masu ba da gudummawa, juriyar haɗin ƙarfe-semiconductor da bambance-bambancen yawan doping na emitter da zurfin junction wasu daga cikin mafi ƙarancin kwanciyar hankali a cikin samarwa da yawa. Su ma suna cikin mafi yawan abubuwan da ke haifar da hauhawar Rs mai kaifi. Juriyar jerin tana da mummunar alaƙa da ma'aunin cika tantanin halitta.

A kan I-V curve, lokacin da Rs ya ƙaru, gangaren yankin forward-bias kusa da Voc yana raguwa kuma curve ɗin ya zama mai laushi. A matakin macroscopic, juriyar jerin mafi girma tana rage iyakar ƙarfin fitarwa kuma tana ja da FF.

Juriyar shunt tana nuna matakin ɗigowar lantarki na ciki. Da kyau, Rsh ya kamata ya kusanci rashin iyaka, ba tare da barin hanyar wucewa ga masu ɗaukar hoto ba. A cikin masana'anta na ainihi, ɗigowar gefe, ɓarnawar crystal, da man ƙarfe da ke shiga cikin PN junction na iya haifar da hanyoyin halitta marasa niyya.

Ƙananan Rsh yana nufin ƙarin ɗigowar lantarki na ciki. Wannan tasirin shunting yana rage halin yanzu da ke wucewa ta hanyar PN junction mai aiki kuma yana rage ƙarfin aiki. Matsalar ta zama mafi bayyane a ƙarƙashin ƙarancin haske saboda halin yanzu da aka samar da hoto ya riga ya yi rauni, yana sa ɗigowa ya zama babban ɓangare na jimlar halin yanzu.

Formula: Ma'aunin Tantanin Rana Tare da Juriyar Parasitic

I = IL - I0 × { exp[q(V + I×Rs)/(n k T)] - 1 } - (V + I×Rs) / Rsh

Ma'ana: Rs yana hana fitar da wutar lantarki, yayin da Rsh ke haifar da hanyar zubewa. Dukansu suna rage FF.

Formula: Yanayin Matsayin Mafi Girman Wutar Lantarki

d(I×V) / dV = 0

Ma'ana: Matsayin da wutar lantarki ta kai mafi girma akan lanƙwasa I-V shine tushen ƙimar Pmax da ake amfani da ita a gwajin samarwa.

Formula: Matsakaicin Juriya na Shunt

RCH = Voc / Isc; rsh = Rsh / RCH

Ma'ana: Daidaitawa tare da juriya na halayen RCH yana ba da damar kwatanta sel masu girma dabam da nau'ikan wutar lantarki akan ma'auni ɗaya.

Formula: Matsakaicin Tasirin Juriya na Shunt akan FF

FFsh ≈ FF0 × (1 - 1 / rsh)

Ma'ana: Idan Rsh ya yi ƙasa, zubewa ya fi tsanani kuma asarar FF ta fi girma.

Wane Matsalolin Samarwa suka dace da Rs da Rsh?

Daga mahangar injiniya, FF yana da mahimmanci ba don kawai yana nuna cewa inganci ya ragu ba. Yana taimaka wa injiniyoyi su gano dalilin da yasa inganci ya ragu. Juriya na jerin da juriya na shunt suna shafar yankuna daban-daban na I-V curve, don haka suna iya nuna lahani daban-daban na masana'anta.

Formula: Asarar Zafi Sakamakon Juriya na Jerin

Ploss ≈ I² × Rs

Ma'ana: A ƙarƙashin yanayin babban wuta ko babban haske, asarar wutar lantarki da Rs ke haifarwa tana ƙaruwa da murabba'in wutar.

Mummunan Tuntuɓi: Matsala Mai Muhimmanci na Metallization

A cikin tsarin aiki daga silicon wafer zuwa tantanin da aka gama, screen printing da metallization firing matakai ne masu mahimmanci waɗanda ke tantance aikin lantarki. Screen printing ya balaga kuma yana da tsada, amma tsarin sadarwar jiki na iya haifar da matsalolin series-resistance da shunt-resistance.

Tantanin halitta masu inganci na zamani suna amfani da rear dielectric passivation da tsarin local metal-contact don rage yawan surface recombination na rear-side carriers. Saboda dielectric layer mai rufi yana tsakanin karfe da jikin silicon, dole ne a samar da local contact ta hanyar laser opening ko paste-assisted etching. Idan ingancin buɗewa ba shi da kyau ko alloying bai isa ba, karfe da semiconductor ba za su iya samar da ingantaccen ohmic contact ba.

Nazarin sel tare da lambobin sadarwa na gaba da aka buga a fuska ya nuna cewa rashin kyakkyawar hulɗa ya sa juriya ta tashi zuwa 21.34 mΩ. Ƙarfin juyawa ya kai kashi 8.95% kawai, wanda ya yi ƙasa da matakin 17.44% na tantanin aluminum na baya.

Masu binciken sun yi ƙoƙarin dawo da FF ta hanyar daidaita matakin doping na manna aluminum na baya. Yayin da adadin aluminum ya ƙaru, zurfin haɗuwa ya inganta kuma juriya ta ragu. Lokacin da adadin aluminum ya kai matsayi mai mahimmanci na 60%, Rs ya ragu da 11 mΩ idan aka kwatanta da yanayin da ba a yi doping ba. Wannan ya ɗaga ƙarfin juyawa da kashi 2.59 cikin ɗari.

Da zarar adadin aluminum ya yi yawa, duk da haka, aluminum mai yawa ya rushe hanyar sadarwa a yankin lamba. Sannan juriya ta sake tashi.

QFLS: Rarraba Lalacewar Kayan aiki daga Lalacewar Masana'antu

Lokacin da layin samarwa ya nuna raguwar FF a ko'ina, ɗayan tambayoyin da suka fi wuya shine ko asarar ta fito ne daga sake haɗuwa mara kyau a cikin kayan ko kuma daga juriya mara kyau da aka gabatar yayin buga allo da harbi.

Rarraba matakin Fermi-kusa, ko QFLS, kayan aiki ne mai mahimmanci na bincike a wannan yanayin. A cikin ma'anar jiki, QFLS yana ƙayyade iyakar wutar lantarki na na'urar photovoltaic lokacin da babu cire cajin waje. Bambanci tsakanin QFLS da iyakar radiyo yana bayyana asarar sake haɗuwa mara radiyo wanda lahani ko ƙazanta ke haifarwa.

Ta hanyar auna QFLS ta hanyar gani da haɗa shi da nazarin J-V na ƙarya mara lamba, masu bincike na iya cire tasirin juriya na jerin daga ma'aunin lantarki na waje.

Idan FF da aka auna ya yi nisa ƙasa da ƙarfin ƙarya da aka samu daga QFLS, asarar yawanci ana iya danganta shi da rashin kyawun haɗin ƙarfe ko yatsun hannu da suka karye. Idan ƙarfin ƙarya ya riga ya yi ƙasa, sake haɗuwa mara radiyo yana iya zama ba a sarrafa shi ba, yana nuna matsala ta asali a cikin ingancin wafer ko kariyar mu'amala.

HJT Azurfa Mannewa Low-Zazzabi: Gina Hanyar Gudanarwa a Ƙarƙashin 200°C

Yayin da fasahohin N-type ke faɗaɗa, HJT da BC sel suna sanya ƙarin buƙatu masu tsauri akan ingancin ƙarfe. Don haka FF ya zama muhimmin alama don kimanta sabbin mannewa masu gudanarwa.

Kwayoyin HJT suna amfani da tsarin haɗin amorphous-silicon da crystalline-silicon heterojunction. Wannan yana ba da kariya mai ƙarfi, amma tsarin yana da matukar damuwa ga zafin jiki. Don hana crystallization da lalacewar fina-finan amorphous-silicon, kwayoyin HJT ba za su iya jure yanayin wuta na al'ada sama da 800°C ba. Suna buƙatar manna azurfa mai ƙarancin zafin jiki tare da sarrafa zafin warkewa sosai a ƙasa da 200°C.

Manna azurfa mai ƙarancin zafin jiki yana aiki daban da manna mai zafin jiki na al'ada. Manna azurfa mai zafin jiki yana dogara da narkewar gilashin frit a yanayin zafi mai girma. Gilashin frit yana tsaga ta cikin fim ɗin antireflection kuma yana haɓaka haɓakar ƙananan azurfa zuwa cikin silicon, yana haifar da lamba ohmic mai ƙarancin juriya.

Manna azurfa mai ƙarancin zafin jiki ya dogara da ƙananan azurfa da aka dakatar a cikin tsarin resin polymer. Bayan ƙafewar sauran ƙarfi a ƙarancin zafin jiki, ana matse ƙananan abubuwa tare don samar da lambobin lantarki na zahiri.

Wannan tsarin gabaɗaya yana ba da manna mai ƙarancin zafin jiki mafi girman juriya fiye da manna mai zafin jiki. Yana iya ƙara jimlar juriya na jerin tantanin halitta kuma ya rage FF. Masu samar da manna suna magance matsalar ta hanyar injiniyan ƙwayar ƙwayar cuta ta nanoscale. Matakan yau da kullun sun haɗa da rage yawan azurfa da inganta laushi da rheology na manna don a samar da hanyar sadarwa mai yawa tare da ƙarancin amfani da azurfa.

BC Cells: FF a matsayin Ƙararrawa ga Rashin Nasara na Rarraba Bayan-gida

Idan ƙalubalen HJT shine ƙarancin wutar lantarki a ƙananan zafin jiki, ƙalubalen ƙwayoyin baya-baya shine iyakokin microscopic na shimfidar lantarki.

Kwayoyin BC suna kawar da inuwar grid na ƙarfe na gaba kuma suna iya tura Isc sama. Abin da ake samu shine cewa dukkan lantarki masu inganci da marasa inganci dole ne a jera su a madadin su a tazara kaɗan a saman baya.

A cikin wannan yanki mai yawan wayoyi, ɗan ƙaramin bugu na allo, yaduwar manna, ko ƙaramin lahani na rufin keɓewa na iya haifar da haɗin jiki tsakanin lantarki masu inganci da marasa inganci. Idan haka ta faru, Rsh na iya faɗuwa kusan zuwa sifili.

Ƙaramin gajeren kewayawa yana haifar da babban shunt current wanda ke cire wutar lantarki mai aiki. Voc yana rushewa kuma FF na iya faɗuwa zuwa sifili. Masu samar da haske da aka ƙirƙira kusa da saman gaba dole ne su yi tafiya mai nisa a kwance kafin su isa ga tattara lantarki na ƙarfe na baya. Wannan yana ƙara haɗarin tara juriya na jiki da na gefe.

Saboda wannan dalili, lura da canjin FF yana ɗaya daga cikin mahimman matakan kariyar amfanin gona akan layin samar da sel BC. Kowace sel da ta kasa cika mizanin FF na iya nuna gazawa a keɓewar ƙarfe ko ƙirar jigilar kaya.

Tagan Firing: Duka Underfiring da Overfiring Ana Hukunta su ta FF

Ga sel TOPCon da PERC, firing mai zafi ɗaya ne daga cikin matakai na ƙarshe masu mahimmanci. Silikon wafers tare da buga na'urorin lantarki na ƙarfe suna wucewa ta cikin tanderun bel tare da matsakaicin zafin jiki na kusan 800°C. Gilashin frit a cikin manna ƙarfe yana narkewa ta cikin rufin saman kuma yana samar da haɗin gami ko kai tsaye tare da silikon da ke ƙasa ko filin baya. Wannan yana haifar da haɗin ohmic kuma yana rage juriyar jerin.

Tsarin aiki ne mai matukar wahala. Zafin da ya yi ƙasa da ƙasa, ko gudun bel da ya yi yawa, yana haifar da underfiring. Gilashin frit ba zai iya narkewa sosai ba kuma yana iya kasa tsallakewa ta cikin silikon nitride ko tunnel oxide. Ƙananan crystallites na azurfa suna hazo kuma suna shiga cikin silikon. Wani rufin insulating ya rage tsakanin ƙarfe da semiconductor, yana sa juriyar haɗin gwiwa ta tashi sosai. Gefen gaba-bias na I-V curve yana daidaitawa, kuma FF ya zama ƙasa da ƙasa.

Zazzabi mai yawa yana haifar da wuce gona da iri. Man karfe ya zama mai tsanani, kuma lu'ulu'u na azurfa na iya shiga cikin ƙaramin PN junction kamar ƙusoshi. Wannan yana haifar da gajerun hanyoyi da wuraren sake haɗuwa. Kariyar lalacewa, Rsh yana raguwa, kuma zubar da ruwa ya zama matsala mai tsanani.

A cikin binciken EL, lalacewar lattice da gazawar kariya sakamakon wuce gona da iri sau da yawa suna bayyana azaman alamu masu hazo, alamomin ruwa, ko alamomin bel na tanderu.

Don faɗaɗa taga tsari, masu samar da kayan aiki sun haɓaka tsarin harbi da allurar haske. Waɗannan tsarin sun haɗa tanderun harbi tare da ɗakin allurar haske. Bayan annealing mai zafi da alloying, wafer ɗin yana fuskantar haske mai ƙarfi kai tsaye a zazzabi na kusan 150-350°C.

Photons masu ƙarfi suna motsa masu ɗaukar kaya kuma suna canza yanayin cajin atom ɗin hydrogen a cikin wafer da kusa da samansa. Wannan na iya kare ƙananan lahani na thermal da igiyoyin da aka ƙirƙira yayin harbi. Sakamakon gwaji ya nuna cewa wannan magani na iya rage alamomin ruwa na EL da alamomin bel na tanderu yayin da yake inganta duka Voc da FF.

LECO: Hanyar da ba ta daidaita ba ta hanyar Rikicin TOPCon Metallization

A lokacin fadada TOPCon na farko, haɗin gaba ya zama babban matsalar yawan amfanin ƙasa. Don rage sake haɗuwa a saman, gefen gaba na tantanin TOPCon yana amfani da emitter mara zurfi tare da ƙarancin doping.

Haɗin gwiwa mara zurfi da ƙarancin doping suna haifar da rikici ga manna azurfa mai zafi na al'ada mai ɗauke da gilashin frit. Idan ba a ƙone manna sosai ba, juriyar lamba ta kasance mai girma sosai. Idan an ƙone shi da ƙarfi sosai, haɗin gwiwa mara zurfi na iya shiga, yana haifar da zubewa da kuma tura FF zuwa sifili.

Haɓaka lamba ta Laser, ko LECO, an ƙirƙira shi don magance wannan rikici. LECO yana amfani da tsarin photoelectric mara daidaiton zafi. Maimakon yin amfani da dumama mai zafi mai lalacewa a duniya, yana tayar da masu ɗaukar caji tare da laser mai ƙarfi yayin amfani da juzu'i na kusan 10 V ko sama.

Ƙarƙashin tasirin haɗin gwiwa mai ƙarfi da masu ɗaukar hoto, wuraren rauni masu rufewa waɗanda ba a haɗa su ta hanyar rashin ƙonewa suna fuskantar rushewar avalanche na gida. Ana tura masu ɗaukar kyauta ta hanyar lambar ƙarfe-semiconductor ta hanyar filin lantarki, suna haifar da igiyoyin gida na amperes da yawa.

Waɗannan igiyoyin ruwa masu ƙarfi suna haifar da zafi na Joule a wuraren tuntuɓar microscopic. Wannan yana haifar da ƙonewa a cikin ƙananan daƙiƙa zuwa daƙiƙa.

LECO yana canza dabarar ƙonewa ta TOPCon daga dumama duniya mai ƙarfi zuwa gyara gida mai niyya. Masu samar da paste za su iya tsara tsarin gilashin frit na musamman da ya dace da LECO. Tsarin ƙonewa na bel na yau da kullun zai iya kasancewa ba a ƙone shi sosai don kare emitter mai zurfi, yayin da LECO ke haifar da rushewar lantarki a ƙarshen baya kuma yana rage juriyar tuntuɓar.

Sakamakon tabbatarwa ya nuna cewa sel ba tare da LECO ba na iya aiki kusa da gazawa saboda yawan juriyar tuntuɓar. Bayan maganin LECO, juriyar tuntuɓar tana raguwa yayin da ake kiyaye passivation. FF yana tashi, yana haifar da ribar ingancin canji na cikakken fiye da maki 0.2 bisa ɗari.

LECO har yanzu yana da iyaka na tsari. Idan hasken yayi ƙasa da ƙasa, gyaran tuntuɓar bai cika ba. Idan ya yi yawa, za a iya samun lalacewar lattice da lalacewar tsari.

Lokacin da ƙarfin laser ya kai ƙimar lalacewa ta 375 MW/cm², FF na iya faɗuwa daga 0.84 zuwa 0.65, raguwa kusan 24%. Voc na iya raguwa daga 0.745 V zuwa 0.695 V, yayin da Jsc ke faɗuwa daga 41.8 mA/cm² zuwa 40.8 mA/cm².

Hanyar sadarwa ta microscopic da LECO ta ƙirƙira tana da matakin rashin daidaituwa na zafi. Binciken EL ya nuna cewa idan tantanin da aka yi wa LECO ya sake yin harbin zafi na biyu, ƙara yawan zafin harbi na biyu daga 280°C zuwa 680°C na iya dagula hanyoyin sadarwa na micro-conductive da aka kafa.

Sannan juriyar sadarwa ta sake yin muni, FF ya ragu sosai, kuma ingancin tantanin farko na 26.35% ya fara raguwa.

FF Ba Kashi Kashi Kawai Ba. Shi Ne Bugun Samar da Noma

Duba cikin akwatin baƙi na masana'antar tantanin hasken rana yana bayyana wani abu a sarari: fill factor ya fi kashi na abstract da aka nuna akan mai gwajin dakin gwaje-gwaje.

A matakin microscopic, FF shine bayanin ƙarshe na jawo tsakanin juriyar jerin da juriyar shunt tare da hanyar jigilar kaya. A kan layin samarwa, yana rikodin iyakokin conductivity na manna metallization, daidaiton injin buga allo, da ƙananan canje-canje a cikin yanayin zafi na tanderun harbin bel.

A cikin sabon zagayowar PV inda farashin da ba na silicon ba ya kusa da ƙasa kuma faɗaɗa jari ya zama mai wahala, kowace babbar fasaha mai inganci tana fuskantar matsala ɗaya ta asali.

Dole ne HJT ta kiyaye hanyar sadarwa mai dogaro a cikin iyakar warkarwa mai ƙarancin zafin jiki. Dole ne ƙwayoyin BC su sarrafa ɓarna tsakanin ingantattun lantarki masu kyau da marasa kyau waɗanda aka raba da nisa kaɗan kawai. TOPCon ta dogara da harbi, allurar haske, da LECO don gyara lamba yayin kare kariya.

Manufar koyaushe ɗaya ce: rage juriyar hulɗar fuska ba tare da shiga cikin haɗin PN da haifar da ɓarna ba.

Ga masana'antun, neman ƙimar inganci cikakke kadai bai isa ba. Tsarin samarwa mai hankali ya kamata ya lura da ƙananan bambance-bambancen FF a ainihin lokaci kuma ya haɗa su da hanyoyin bincike marasa lalacewa kamar QFLS da nazarin J-V na ƙarya. Wannan ita ce hanya mai amfani zuwa ga ƙirƙirar ƙwayoyin hasken rana masu inganci na gaba mai karko.

Ra'ayin Ooitech

Ƙimar gaskiya ta FF ita ce saurinta a matsayin faɗakarwar samarwa. Layi mai karko ya kamata ya bi FF tare da Rs, Rsh, tsarin EL, pseudo-FF, zafin harbi, da bayanan ƙarfe maimakon kula da kowane sakamako daban. Ga fasahohin TOPCon, HJT, da BC, wannan tarin bayanai na iya bayyana taga tsari mai canzawa kafin rarraba inganci na ƙarshe ya nuna asarar yawan amfanin ƙasa mai tsanani.