(Lithium hlau anode) Interfacial theem ntawm cov electrolyte khoom tshiab anion-derived

Cov Khoom Siv Hluav Taws Xob Khoom Siv Hluav Taws Xob (SEI) yog siv dav los piav qhia txog theem tshiab tsim ntawm anode thiab electrolyte hauv cov roj teeb ua haujlwm. Cov roj teeb lithium (Li) hlau muaj zog ntau raug cuam tshuam los ntawm dendritic lithium deposition coj los ntawm SEI tsis sib xws. Txawm hais tias nws muaj cov txiaj ntsig tshwj xeeb hauv kev txhim kho qhov sib xws ntawm lithium deposition, hauv kev siv ua haujlwm, cov nyhuv ntawm anion-derived SEI tsis zoo tagnrho. Tsis ntev los no, Zhang Qiang pawg tshawb fawb los ntawm Tsinghua University tau tawm tswv yim siv anion receptors los kho cov qauv electrolyte los tsim kom muaj anion-derived SEI ruaj khov. Tris (pentafluorophenyl) borane anion receptor (TPFPB) nrog electron-deficient boron atoms cuam tshuam nrog bis (fluorosulfonimide) anion (FSI-) los txo qhov kev ruaj khov ntawm FSI-. Tsis tas li ntawd, nyob rau hauv qhov muaj TFPPB, hom ion clusters (AGG) ntawm FSI- hauv electrolyte tau hloov pauv, thiab FSI- cuam tshuam nrog ntau Li +. Yog li ntawd, qhov kev rhuav tshem ntawm FSI- raug txhawb kom tsim Li2S, thiab qhov ruaj khov ntawm anion-derived SEI tau zoo dua.

SEI yog tsim los ntawm cov khoom lag luam reductive decomposition ntawm electrolyte. Cov khoom sib xyaw thiab cov qauv ntawm SEI feem ntau yog tswj los ntawm cov qauv ntawm electrolyte, uas yog, kev sib cuam tshuam ntawm cov kuab tshuaj, anion, thiab Li +. Cov qauv ntawm electrolyte hloov tsis yog tsuas yog nrog hom kuab tshuaj thiab lithium ntsev, tab sis kuj nrog qhov concentration ntawm ntsev. Nyob rau hauv xyoo tas los no, high-concentration electrolyte (HCE) thiab localized high-concentration electrolyte (LHCE) tau qhia txog qhov zoo tshwj xeeb hauv kev ruaj khov lithium hlau anodes los ntawm kev tsim SEI ruaj khov. Qhov piv ntawm cov kuab tshuaj rau lithium ntsev yog qis (tsawg dua 2) thiab anions raug qhia rau hauv thawj solvation sheath ntawm Li +, tsim cov contact ion pairs (CIP) thiab aggregation (AGG) hauv HCE lossis LHCE. Cov khoom sib xyaw ntawm SEI tom qab ntawd raug tswj los ntawm anions hauv HCE thiab LHCE, uas hu ua anion-derived SEI. Txawm hais tias nws muaj kev ua tau zoo hauv kev ruaj khov lithium hlau anodes, tam sim no anion-derived SEIs tsis txaus los daws cov teeb meem ntawm cov xwm txheej ua tau zoo. Yog li ntawd, nws yog qhov tsim nyog los txhim kho qhov ruaj khov thiab kev sib xws ntawm anion-derived SEI kom kov yeej cov teeb meem hauv qab cov xwm txheej tiag tiag.

Cov Anions hauv daim ntawv ntawm CIP thiab AGG yog cov ua ntej tseem ceeb rau anion-derived SEI. Feem ntau, cov qauv electrolyte ntawm anions yog tswj hwm tsis ncaj qha los ntawm Li +, vim tias qhov them zoo ntawm cov kuab tshuaj thiab cov tshuaj diluent tsis muaj zog thiab tsis tuaj yeem cuam tshuam ncaj qha nrog anions. Yog li ntawd, cov tswv yim tshiab rau kev tswj hwm cov qauv ntawm anionic electrolytes los ntawm kev cuam tshuam ncaj qha nrog anions yog qhov xav tau heev.