Esinye sezici zokusebenza ezibaluleke kakhulu zeamabhethri okugcina amandlawukusebenza kwabo kokukhishwa. Ukuze ubonise indlela ibhethri elisebenza ngayo ngaphansi kwezimo ezihlukene, kuyadingeka ukukala ijika lokuphuma kwebhethri, okuvamise ukuba ijika elibonisa ukuguqulwa kwamandla kagesi wokulahla ngokuhamba kwesikhathi. Izimo ezihlukene zokukhishwa zibonakala ngamasu okukhipha, futhi amasu ahlukene okukhipha azoholela emigqeni ehlukene yokukhipha. Amasu okukhipha ngokuvamile ahlanganisa indlela yokukhipha, amandla okukhipha, i-voltage yokuqeda, kanye nezinga lokushisa elizungezile.
Indlela yokukhipha
Kunezindlela ezintathu ibhethri elingakhipha ngazo: ukuphuma kwamanje okungaguquki, ukukhipha okunganqamuki okungaguquki, kanye nokuphuma kwamandla okungashintshi. Amajika okukhipha avamile aboniswa kuMfanekiso 1-5, obonisa izinguquko kumanje okukhiphayo, i-voltage, namandla ngaphezu kwesikhathi sokukhipha ngaphansi kwalezi zindlela ezintathu zokukhipha.
Phakathi nokukhipha-ukumelana okungaguquki, amandla omthamo webhethri okusebenza namandla okuphuma ayancipha kancane kancane ngokuhamba kwesikhathi. Ngokufanayo, ngaphansi kokukhishwa okungashintshi-kwamanje, i-voltage yokusebenza nayo iyehla njengoba inqubo yokukhipha iqhubeka. Lokhu kuncipha kwe-voltage yokusebenza ngesikhathi sokukhipha isikhathi eside kungenxa yokwanda kokumelana kwangaphakathi kwebhethri. Ngaphezu kwalokho, ngokwanda kokusetshenziswa kwamandla ebhethri kumathuluzi kagesi, ezimotweni zikagesi, nezinye izinhlelo zokusebenza, -ukuphuma kwamandla okungashintshi kuya kuvame kakhulu. Ngesikhathi-aphuma amandla angashintshi, amandla omthamo webhethri alokhu ehla ngokuqhubekayo kuyilapho amandla okuphuma akhuphuka ngokuqhubekayo njengoba ukuphuma kuqhubeka.
Ukukhipha okwamanje
Ngesikhathi sokusebenza kwebhethri, i-current ephumayo ibizwa ngokuthi i-discharge current. Amanzi okukhipha nawo avame ukubizwa ngokuthi izinga lokukhipha, futhi kuvame ukuvezwa kusetshenziswa isilinganiso sehora (esaziwa nangokuthi isilinganiso sehora) kanye nesiphindaphindi.
Izinga lokukhishwa lisho izinga ibhethri eliphuma ngalo, likalwa ngesikhathi sokuphuma. Ngokucacile, isikhathi esidingekayo ukuze ukhulule ngokugcwele umthamo webhethri usebenzisa i-fluorensi ethile, ngokuvamile evezwa ngamahora (h). Isibonelo, kubhethri elinomthamo olinganiselwe wamahora angu-10 amp-amahora (A·h), uma lishajwa ngomsinga ongu-2A, izinga lokukhipha elihambisanayo amahora angu-5 (10A·h/2A=5h), okusho ukuthi ibhethri liyashajwa ngenani lamahora angu-5.
Izinga lokuchithwa libhekisela enanini lamanje, elivezwa njengokuphindaphinda komthamo olinganiselwe webhethri, lapho umthamo ogcwele webhethri ukhishwa ngokugcwele phakathi nesikhathi esithile. Isibonelo, ukukhishwa kwe-2C kusho ukuthi amandla okukhipha aphindwe kabili umthamo olinganiselwe webhethri, ngokuvamile umelwe ngu-2C (lapho u-C umele umthamo olinganiselwe webhethri). Kubhethri elinomthamo olinganiselwe ongu-10A·h, 2C okukhiphayo (kunenkinga yobukhulu lapha, okungukuthi, amayunithi womthamo newamanje awafani, kodwa lokhu kuwukusetshenziswa okuvamile, ngakho ngeke kushintshwe) kusho ukuthi ukukhishwa kwamanje ngu-2 x 10=20 (A), okuhambisana nesilinganiso sokukhipha esingu-0.5h. Izinhlobo ezihlukene namadizayini amabhethri unokuvumelana nezimo ezihlukile ezimweni zokushajwa: ezinye zifaneleka kakhulu{12}}zokukhishwa okuphansi kwamanje, kuyilapho ezinye zenza kangcono kumaza aphezulu. Ngokuvamile, amazinga okukhishwa angaphansi noma alingana no-0.5C abizwa ngokuthi amanani aphansi; lawo aphakathi kuka-0.5C no-3.5C abizwa ngokuthi amanani aphakathi; lawo aphakathi kuka-3.5C no-7C abizwa ngokuthi amanani aphezulu; futhi lawo angaphezu kuka-7C abizwa ngokuthi-amazinga aphezulu kakhulu.
I-voltage yokuqeda
Ngesikhathi sokukhishwa kwebhethri, inani lokuqala le-voltage lichazwa njenge-voltage yokuqala yokusebenza; lapho i-voltage yehla ifika embundwini lapho ukuphuma okwengeziwe kungasafaneleki, leli phuzu likagesi libizwa ngokuthi i-termination voltage. Inani elithile lala mandla kagesi wokunqanyulwa livamise ukusethwa umhloli ngokusekelwe ezidingweni zangempela zokuhlola nolwazi lwangaphambilini.
Isethi yevoltheji yokunqamula iyahlukahluka kuye ngezimo ezihlukene zokukhipha kanye nomthelela wazo kumthamo webhethri nempilo yokuphila. Ama-voltage aphansi okunqamula ngokuvamile asetshenziswa-ezindaweni zethempelesha eziphansi noma ngaphansi-izimo zamanje zokuphuma eziphezulu, kuyilapho ama-voltage aphezulu okunqamula ngokuvamile asethwa ngaphansi{3}ezimo eziphansi zamanje zokukhishwa. Lokhu kungenxa yokuthi i-polarization phakathi kwama-electrode ebhethri inyuka kakhulu ngesikhathi-izinga lokushisa eliphansi noma eliphezulu{6}}lokuphuma kwamanje, okuholela ekusetshenzisweni okungaphelele kwezinto ezisebenzayo kanye nokwehla kwe-voltage ngokushesha. Ngakho-ke, ukwehlisa ngokufanelekile i-voltage yokuqeda kusiza ukukhulula amandla engeziwe. Ngokuphambene, uma usebenzisa ukukhishwa{9}}okuphansi kwamanje, izingxenye ezisebenzayo ebhethrini zisetshenziswa ngokugcwele. Kulesi simo, ukukhulisa amandla kagesi wokunqanyulwa ukuze kukhawulwe ukuchithwa okujulile kunganweba ngempumelelo yonke impilo yebhethri.
Izinga lokushisa le-ambient
Njengoba kuboniswe kuMfanekiso 1-6, izinga lokushisa le-ambient linomthelela omkhulu ejikeni lokukhipha. Emazingeni okushisa aphezulu, ijika lokukhipha libonisa umkhuba omnene; nokho, njengoba izinga lokushisa lincipha, lolu shintsho luba lubi nakakhulu. Isizathu esiyisisekelo ukuthi emazingeni okushisa aphansi, izinga lokufuduka kwama-ion liyancipha, okuholela ekwandeni kokumelana ne-ohmic yangaphakathi. Ezimweni ezimbi kakhulu, uma izinga lokushisa liphansi kakhulu, i-electrolyte ingase ibe yiqhwa, ngaleyo ndlela ivimbele inqubo evamile yokukhipha ibhethri. Ngaphezu kwalokho, emazingeni okushisa aphansi, i-electrochemical polarization kanye ne-concentration polarization iyathuthukiswa ngokuhambisanayo, okuqhubekisela phambili ukusheshisa izinga lokubola kwejika lokuphuma.
Umfanekiso 1-6 Khipha amajika amabhethri e-lead-acid emazingeni okushisa ahlukene
Amandla namandla athile
Umthamo webhethri usho inani likagesi elingatholwa ebhethri ngaphansi kwezimo ezithile zokuphuma. Iyunithi ivamise ukuvezwa njengehora le-ampere-(Ah). Kuye ngesimo sangempela, umthamo webhethri ungahlukaniswa futhi ube umthamo wethiyori, umthamo wangempela, namandla alinganiselwe.
Umthamo wetiyori (Co) ubhekisela enanini likagesi elinganikezwa ngaphansi kwezimo ezikahle lapho into esebenzayo ibamba iqhaza ngokugcwele ekuphenduleni kwe-electrochemical yebhethri. Leli nani libalwa ngokusekelwe kubukhulu bezinto ezisebenzayo, ngokulandela umthetho kaFaraday. Umthetho kaFaraday uthi kukhona ubudlelwano obuqondile obulinganayo phakathi kwenqwaba yezinto ezibamba iqhaza ekuphenduleni ku-electrode kanye nenani lenkokhiso eliyidluliselayo; uma i-mol engu-1 yezinto ezisebenzayo ibamba iqhaza kunqubo ye-electrochemical yebhethri, ingakhulula ukushaja okulingana no-26.8 A·h noma 1 farad (F). Ngakho-ke, ifomula yokubala elandelayo ikhona:
Kufomula, u-m uyisisindo sento esebenzayo lapho isabela ngokuphelele; n inombolo yama-electron azuziwe noma alahlekile ngesikhathi sokusabela kokugeleza; futhi u-M uyi-molar mass yento esebenzayo.
Kufomula, u-K ubizwa ngokuthi i-electrochemical equivalent yesithako esisebenzayo.
Njengoba kuboniswe kuzibalo (1.5), umthamo wetiyori we-electrode uhlobene nesisindo sento esebenzayo kanye nokulingana kwe-electrochemical. Ngesisindo esifanayo sezinto ezisebenzayo, okulinganayo okulinganayo kwe-electrochemical, kukhudlwana umthamo wetiyori. Ukulingana kwe-electrochemical kwezinye izinto ze-electrode kuboniswa kuThebula 1-3.
Ithebula 1-3 Ama-Electrochemical Equivalents of Some Electrode Materials
| I-Negative Electrode Material | Ukuminyana (g/cm³) | Umthamo othize (mA·h/g) | I-Positive Electrode Material | Ukuminyana (g/cm³) | Umthamo othize (mA·h/g) |
|---|---|---|---|---|---|
| H₂ | - | 0.037 | O₂ | - | 0.30 |
| Li | 0.534 | 0.259 | I-SOCl₂ | 1.63 | 2.22 |
| Mg | 0.74 | 0.454 | I-AgO | 7.4 | 2.31 |
| Al | 2.699 | 0.335 | SO₂ | 1.37 | 2.38 |
| Fe | 7.85 | 1.04 | MnO₂ | 5.0 | 3.24 |
| Zn | 7.1 | 1.22 | NiOOH | 7.4 | 3.42 |
| Cd | 8.65 | 2.10 | I-Ag₂O | 7.1 | 4.33 |
| (Li)Cl₂ | 2.25 | 2.68 | I-PbO₂ | 9.3 | 4.45 |
| Pb | 11.34 | 3.87 | I₂ | 4.94 | 4.73 |
Ngaphezu kwalokho, imiqondo yomthamo wangempela namandla alinganisiwe avame ukusetshenziswa. Umthamo wangempela ubhekisela enanini eliphelele likagesi ibhethri elinganikeza ngaphansi kwezimo ezithile zokuchithwa. Umthamo wangempela awunqunyelwe kuphela ngenani eliphezulu lethiyori kodwa nangezimo ezithile zokukhishwa.
Umthamo olinganiselwe, ngakolunye uhlangothi, isethi evamile yebhethri ngesikhathi sokuklama kanye nenqubo yokukhiqiza; okungukuthi, ubuncane bomthamo wokukhiphayo okufanele ibhethri iwuthole ngaphansi kwezimo ezithile zokukhipha, ezaziwa nangokuthi umthamo wegama.
Uma kuqhathaniswa izinhlobo ezahlukene zamabhethri ngaphakathi kochungechunge olufanayo, umthamo othize uvame ukusetshenziselwa ukuhlolwa. Ngokukhethekile, umthamo othize ubhekisela enanini likagesi ibhethri elinganikeza ngeyunithi yesisindo noma ivolumu, okungukuthi, umthamo othize wesisindo (Ah/kg) kanye nomthamo othize wevolumu (Ah/L). Kubalulekile ukuqaphela ukuthi lapho ubala ubukhulu nevolumu yebhethri, ngaphezu kokucabangela izinto ze-electrode kanye ne-electrolyte, ezinye izingxenye zebhethri kufanele futhi zicatshangelwe, njenge-casing, isihlukanisi, nezingxenye ezihambisanayo zokuqhuba. Ikakhulukazi kumabhethri okugcina kanye namaseli kaphethiloli, isamba sengqikithi nevolumu kuphinda kufake zonke izinto ezisizayo ezidingekayo, ezifana namathangi okugcina uketshezi, amadivaysi okuqalisa (amabhethri okugcina), noma amasistimu asebenzayo okulondoloza nokokuphakela, amasistimu okulawula, amayunithi okushisa, njll. (kumaseli kaphethiloli).
Ngokwethula umqondo womthamo othize, singaqhathanisa ukusebenza kwamabhethri ezinhlobo ezahlukene nosayizi. Umthamo webhethri uhlukaniswe ngomthamo wethiyori kanye nomthamo wangempela; ngokuhambisanayo, umthamo othize nawo unezici zethiyori nezingokoqobo.
Amandla namandla athile
Amandla ebhethri asho inani lamandla kagesi eliphelele elikhishwa ibhethri lapho lenza umsebenzi ngaphansi kwezimo ezithile zokuchithwa, ngokuvamile zivezwa ngamahora angu-watt-(W·h). Amandla ebhethri nawo anamandla athiyori kanye namandla angempela.
Uma sicabanga ukuthi ibhethri lihlala lilingana ngesikhathi liphuma futhi i-voltage yalo yokukhipha ihlale ilingana namandla ayo e-electromotive, futhi kucatshangwa ukuthi zonke izinto ezisebenzayo zibamba iqhaza ekuphenduleni kwamakhemikhali, khona-ke amandla anikezwa ibhethri kufanele alingane namandla ayo angokwengqondo aphezulu Wo.
Amandla acatshangwayo ebhethri umsebenzi omkhulu ongewona{0}}ongewona wevolumu owenziwe ibhethri ngaphansi kwezinga lokushisa elingashintshi, ukucindezela okungaguquki, nezimo zokukhipha okubuyiselekayo.
Amandla angempela (W) abhekisele kumandla ahlinzekwa yibhethri ngaphansi kwezimo ezithile zokuphuma. Itholakala ngokwezinombolo ngokuphindaphinda umthamo wangempela nge-voltage yokusebenza evamile. Ngenxa yokuthi izinto ezisebenzayo ngaphakathi kwebhethri azikwazi ukusetshenziswa ngokugcwele, futhi i-voltage yayo yokusebenza ngokuvamile ingaphansi kwamandla e-electromotive ethiyori, amandla angempela ahlala engaphansi kwamandla acatshangwayo.
Amandla athile asho amandla akhishwa ibhethri ngeyunithi yesisindo noma ivolumu yeyunithi. Amandla aphumayo ngeyunithi yesisindo sebhethri achazwa njengamandla athize, ngokuvamile akalwa ngama-watt-amahora ngekhilogremu (Wh/kg). Amandla aphumayo ngeyunithi ngayinye yevolumu ichazwa njengamandla athile evolumu, ngokuvamile avezwa ngama-watt-amahora ilitha ngalinye (Wh/L). Ngaphezu kwalokho, umqondo wamandla athile ungaphinda uhlukaniswe ngokwethiyori (W) kanye nengokoqobo (W), lapho amandla acacisiwe wethiyori angabalwa kusetshenziswa isibalo (1.9):
Kufomula, i-K+ ilingana ne-electrochemical yezinto ezibonakalayo ze-electrode; I-K- ilingana ne-electrochemical ye-negative electrode material; futhi u-E ungamandla ebhethri e-electromotive.
Amandla namandla athile
Amandla ebhethri asho amandla aphumayo ebhethri ngesikhathi seyunithi ngayinye ngaphansi kwezimo ezithile zokuphuma, futhi iyunithi yayo yokulinganisa i-watt (W) noma i-kilowatt (kW). Uma la mandla okukhiphayo ecatshangelwa ngokuhlobene nesisindo noma ivolumu yebhethri, umqondo wamandla athile uyatholwa. Ngokukhethekile, amandla akhethekile akala ukuthi mangaki ama-watts wamandla iyunithi yesisindo sebhethri engawanikeza, futhi iyunithi yawo ingu-W/kg; kuyilapho amandla athile evolumu ebonisa amandla akhiqizwa umthamo weyunithi yebhethri, futhi iyunithi yayo ehambisanayo ingu-W/L.
Amandla namandla athile akhombisa izinga lokuphuma kwebhethri. Amandla ebhethri aphezulu asho ukuthi ibhethri ingaphuma ngamanani aphezulu wamanje noma aphezulu. Isibonelo, ibhethri le-zinc{2}}lingakwazi ukuthola amandla athile angaphezu kuka-100 W/kg lapho likhipha ukuminyana kwamanje, okubonisa ukumelana okuphansi kwangaphakathi nokusebenza okuhle{4}}kwezinga eliphezulu. Ngokuphambene, ibhethri leseli elomile le-zinc{6}}manganese lingathola kuphela amandla athile angu-10 W/kg uma lisebenza ngokuminyana kwamanje okuphansi, okubonisa ukumelana okuphezulu kwangaphakathi kanye{8}}nezinga eliphezulu elingasebenzi kahle lokukhipha. Ngokufana namandla ebhethri, amandla nawo anamandla okucabanga kanye namandla angempela.
Amandla etiyetha ebhethri angavezwa kanje:
Efomini, t isikhathi; I-Co umthamo wethiyori webhethri; mina ngingumsinga.
Amandla wangempela ebhethri kufanele abe:
Kufomula, I2U-R umele amandla asetshenziswe ukumelana kwangaphakathi kwebhethri. Lawa mandla awasizi kumthwalo osetshenzisiwe; iguqulwa ibe amandla okushisa futhi ikhishwe njengokushisa.
Impilo yomjikelezo
Kumabhethri, impilo yomjikelezo, noma umjikelezo wokusetshenziswa, kungenye yezinkomba ezibalulekile zokuhlola ukusebenza kwebhethri. Umjikelezo ngamunye wokushaja{1}}ophelele uthathwa njengenkathi yesikhathi sebhethri.
Ngaphansi kwezimo ezithile zokushaja{0}}zokukhipha, inani lemijikelezo ibhethri elingakwazi ukumelana nayo ngaphambi kokuba umthamo walo wehlele kunani elithile elicacisiwe lichazwa njengomjikelezo wempilo yalo noma umjikelezo wokusetshenziswa. Uma ubude bempilo yomjikelezo, kuba ngcono ukusebenza komjikelezo webhethri.Izinhlobo ezahlukene zamabhethri zibonisa ukuphila komjikelezo ohlukile; isibonelo, amabhethri e-nickel-e-cadmium angakwazi ukufeza izinkulungwane zemijikelezo, kuyilapho amabhethri e-zinc{4}}esiliva anemijikelezo embalwa uma kuqhathaniswa, amanye angaphansi kwekhulu. Kuyaphawuleka ukuthi ngisho namabhethri ohlobo olufanayo angaba nezimpilo zomjikelezo ohlukile ngenxa yokuhluka kwesakhiwo sawo sangaphakathi.
Impilo yomjikelezo webhethri ithintwa izinto ezahlukahlukene. Ngaphezu kokusetshenziswa nokunakekelwa okufanele, izici ezibalulekile ezilandelayo ziyasebenza: ① Ngesikhathi sokushaja{1}}imijikelezo yokukhipha, indawo engaphezulu yento esebenzayo iyancipha kancane kancane, okuholela ekwenyukeni kokuminyana okusebenzayo kwamanje kanye ne-polarization eqinile; ② Izingxenye ezisebenzayo kuma-electrode zingase zihlukanise noma zidlulise; ③ Ngesikhathi sokusebenza kwebhethri, ezinye izinto ze-electrode zingagqwala; ④ Ama-dendrite akheke kuma-electrode ngesikhathi sokuhamba ngebhayisikili angase abangele amasekhethi amafushane ngaphakathi kwebhethri; ⑤ Isihlukanisi singalimala; ⑥ I-crystal morphology yezinto ezisebenzayo iyashintsha phakathi nokushaja okuphindaphindiwe{2}}komjikelezo wokukhipha, ngaleyo ndlela kunciphisa umsebenzi wayo.
Ukusebenza kwesitoreji
Ukusebenza kwesitoreji sebhethri kusho izinga lokulahleka kwamandla emvelo ngaphakathi kwebhethri uma isendaweni evulekile-yesifunda ngaphansi kwezimo ezithile zemvelo (ezifana nezinga lokushisa kanye nomswakama). Lesi simo saziwa nangokuthi ukuzikhulula. Uma isilinganiso sokulahlekelwa amandla ngesikhathi sokulondoloza sisincane, lokho kubonisa ukuthi ibhethri linokusebenza okuhle kakhulu kwesitoreji.
Uma ibhethri lisesimweni-sesekhethi evulekile, nakuba linganikezi amandla kagesi ngaphandle, lisacubungula{1}}ukuzikhipha. Lesi simo sibangelwa ikakhulukazi ukungazinzi kwe-thermodynamic kwama-electrode endaweni ye-electrolyte, okuholela ekuphenduleni okuzenzakalelayo kwe-redox phakathi kwama-electrode. Ngisho nangaphansi kwezimo ezomile, uma isivalo singaqinile ngokwanele, ukungena kwezinto zangaphandle ezifana nomoya noma umswakama kusengadala umphumela wokuzikhipha ngaphakathi kwebhethri.
Izinga lokuzikhipha ngokwakho lingavezwa njengenani lezinsuku elizithathayo ukuze umthamo webhethri wehle ube inani elishiwo lapho ligcinwe, elaziwa ngokuthi ukuphila kweshelufu. Kukhona impilo yeshelufu eyomile kanye nempilo yeshelufu emanzi. Isibonelo, ibhethri yesitoreji, ngaphandle kokwengeza i-electrolyte ngaphambi kokusetshenziswa, ingagcinwa isikhathi eside; ibhethri elinjalo lingaba neshalofu ende elomile. Isitoreji esine-electrolyte sibizwa ngokuthi isitoreji esimanzi; ukugcinwa okumanzi kubangela-umphumela oqinile wokuzikhipha kanye nempilo yeshelufu emanzi emfushane. Isibonelo, ibhethri le-zinc{6}}eliyisiliva lingaba nempilo yeshelufu elomile leminyaka engu-5–8, kanti impilo yalo yeshelufu emanzi ngokuvamile iyizinyanga ezimbalwa.