Kuyini ukumelana kwangaphakathi kwebhethri le-lithium?
Uma i-current igeleza ngaphakathi kwebhethri, ihlangabezana nokumelana, okubangela ukuncipha kwamandla okusebenza ebhethri. Lokhu kumelana kubizwa ngokuthi ukumelana kwangaphakathi kwebhethri. Ngenxa yokumelana nebhethri kwangaphakathi, i-terminal voltage ingaphansi kwamandla e-electromotive futhi ivula-i-circuit voltage ngesikhathi sokuyikhipha. Ngesikhathi sokushaja, i-terminal voltage ingaphezu kwamandla e-electromotive futhi ivula-i-circuit voltage. Ukumelana nebhethri kwangaphakathi kuyipharamitha ebaluleke kakhulu yomthombo wamandla wamakhemikhali. Ithinta ngokuqondile amandla omthamo wokusebenza webhethri, amandla okusebenza, amandla aphumayo, namandla. Ukuze uthole umthombo wamandla wamakhemikhali asebenzayo, ukuncipha kokumelana kwangaphakathi, kungcono.
Ukumelana nebhethri kwangaphakathi akuhlali njalo; iyahlukahluka ngesikhathi sokukhishwa kuye ngokubunjwa kwezinto ezisebenzayo, ukugxila kwe-electrolyte, izinga lokushisa lebhethri, nesikhathi sokukhipha. Ukumelana kwangaphakathi kwebhethri kuhlanganisa ukumelana kwangaphakathi kwe-ohmic (R₀) kanye nokumelana kwangaphakathi kwe-polarization (Rf) okuboniswa ama-electrode ngesikhathi sokusabela kwe-electrochemical. Isamba salokhu okubili sibizwa ngokuthi i- total internal resistance (Rw) yebhethri.
Ukumelana kwangaphakathi kwe-Ohmic ikakhulukazi kwakhiwe ukumelana kwangaphakathi kwezinto ze-electrode, i-electrolyte, isihlukanisi, nokumelana nokuxhumana kwezingxenye ezahlukahlukene. Kuhlobene nosayizi webhethri, ukwakheka, indlela yokwenza i-electrode (isb, ukunamathisela-uhlobo nama-electrode eshubhu kumthofu{4}amabhethri e-asidi, kanye nohlobo-lohlobo lwebhokisi nama-electrode a-sintered kumabhethri e-alkaline), kanye nokuqina kokuhlanganiswa. Ukuphikiswa kwangaphakathi kwe-Ohmic kuthobela umthetho ka-Ohm.
Ukumelana kwangaphakathi kwe-polarization kubhekisela ekuphikiseni kwangaphakathi okubangelwa ukuhlukaniswa phakathi kwama-electrode amahle namabi omthombo wamandla wamakhemikhali ngesikhathi sokusabela kwe-electrochemical. Yisamba sokumelana okubangelwa i-electrochemical polarization kanye nokugxila
i-polarization.
Ukumelana kwangaphakathi kwe-polarization kuhlobene nemvelo yezinto ezisebenzayo, isakhiwo se-electrode, nenqubo yokukhiqiza ibhethri, ikakhulukazi ehlobene eduze nezimo zokusebenza kwebhethri; ukukhishwa kwamanje kanye nezinga lokushisa kunomthelela omkhulu. Ngesikhathi sokukhishwa kwe-high density yamanje, kokubili i-electrochemical polarization kanye ne-concentration polarization kuyanda, okungenzeka kubangele ngisho nokudlula kwe-electrode engalungile, ngaleyo ndlela kwandise ukumelana ne-polarization yangaphakathi. Amazinga okushisa aphansi athinta kabi i-electrochemical polarization kanye nokusabalalisa kwe-ion; ngakho-ke, ukumelana nebhethri kwe-polarization kuyenyuka ngaphansi-kwezimo zezinga lokushisa eliphansi. Ngakho-ke, ukumelana ne-polarization akuyona into eqhubekayo, kodwa izinguquko ngesilinganiso sokukhishwa, izinga lokushisa nezinye izimo.
Isisho sokuhlaziya sokumelana kwangaphakathi kwebhethri simi kanje:
Kufomula, i-bE (iₐ,τ,C) Iₐ⁻¹-Ukumelana kwangaphakathi kwe-polarization yebhethri;
b-I-coefficient of variation ye-voltage yetheminali yebhethri ngokuhlobene netheminali yebhethri engu-E ngaphansi kwezimo zomthamo olinganiselwe lapho ibhethri ishajwa futhi ishajwa nge-Iₐ yamanje;
Rₑₗ(τ,C)-Ukumelana ne-electrolyte;
Rₑ(C)-Ukumelana ne-Electrode. Ukumelana ne-electrolyte Rₑₗ kanye nokumelana ne-electrode Rₑ kuhambisana ngokuphambene nomthamo osheshayo webhethri;
iₐ, τ, C-Ukushaja kwebhethri nokukhipha amandla kwamanje, izinga lokushisa, nesimo somthamo ngaleso sikhathi.
Ukumelana nebhethri kwangaphakathi kuncane uma kuqhathaniswa futhi kuvame ukungabi nandaba ngaphansi kwezimo eziningi zokusebenza. Kodwa-ke, amabhethri amandla ezimoto zikagesi ngokuvamile asebenza ngaphansi kwezimo eziphezulu zamanje nezijulile zokukhishwa, okuholela ekwehleni okukhulu kwamandla kagesi okubangelwa ukumelana kwangaphakathi. Kulesi simo, umthelela wokumelana kwangaphakathi kuwo wonke umjikelezo awukwazi ukunakwa.
