Ama-cathodes asekelwe ku-silicon azinzisa amaseli e-Li-S. Umphumela: imijikelezo yokushaja engaphezu kwemi-2 esikhundleni seshumi nambili

Ososayensi abavela ku-Daegu Institute of Science and Technology (DGIST, South Korea) benze i-cathode esekwe ku-silicon okulindeleke ukuthi imelane nemijikelezo yokushaja engaphezu kwemi-2 kumaseli e-Li-S. Amaseli e-lithium-ion asendulo asebenzisa i-silicon emsulwa kuma-anode ukuze agcwalise futhi athathe indawo yegraphite kancane kancane. I-silicon oxide yayisetshenziswa lapha, futhi i-silicon dioxide yayisetshenziswa ku-cathode.

Iseli ye-Li-S = i-lithium anode, i-silicon dioxide cathode enesulfure

Amaseli e-Li-S abhekwa njengethakazelisa ngenxa yokuminyana kwawo okuphezulu kwamandla, isisindo kanye nezindleko eziphansi zokukhiqiza. Nokho, akekho noyedwa okwazile ukudala inguqulo engamelana nemijikelezo yokushaja engaphezu kweshumi nambili. Konke ngenxa ye-lithium polysulfides (LiPS), encibilika ku-electrolyte ngesikhathi sokukhishwa futhi isabela nge-anode, inciphisa umthamo wayo futhi, ngenxa yalokho, ibhubhise ibhethri.

Kungenzeka ukuthi abacwaningi baseNingizimu Korea bathole isisombululo kule nkinga. Esikhundleni sezinto ezisekelwe ku-carbon (njenge-graphite), basebenzisa i-cathode. Isakhiwo se-lamellar se-silica ye-mesoporous (POMS).

Isakhiwo se-lamellar siyaqondakala, kuyilapho i-mesoporosity ibhekisela ekuqoqweni kwezimbotshana (izimbobo) ku-silica ezinosayizi oqondiwe, ukuminyana kwendawo kanye nokuhlakazeka kosayizi omncane (umthombo). Lokhu kufana nokugqobhoza amapuleti aseduze ohlobo oluthile lwe-silicate njalo ukwenza isisefo.

Ososayensi be-DGIST basebenzise lezi zimbobo ukufaka isulfure kuzo (Umfanekiso a). Ngesikhathi sokukhishwa, isibabule siyancibilika futhi sakhe i-lithium polysulfides (LiPS) nge-lithium. Ngakho-ke, ukushaja kugeleza, kodwa i-LiPS ihlala ibambekile eduze kwe-cathode ngenxa ye-carbon factor eyengeziwe engacacisiwe (isakhiwo esimnyama, isibalo b).

Ngesikhathi sokushaja, i-LiPS ikhipha i-lithium, ebuyiselwa ku-lithium anode. Ngakolunye uhlangothi, isibabule siguqulwa sibe yi-silica. Akukho ukuvuza kwe-LiPS ku-anode, akukho monakalo wensimbi.

Ibhethri ye-Li-S edalwe ngale ndlela igcina umthamo omkhulu nokuzinza kwemijikelezo yokusebenza engaphezu kwemi-2. Okungenani imijikelezo yokusebenza engu-500-700 ibhekwa njengejwayelekile kumaseli e-Li-ion yakudala, nakuba kufanele kwengezwe ukuthi amaseli e-lithium-ion acutshungulwe kahle angakwazi ukumelana nemijikelezo eyizinkulungwane ezimbalwa.