TY - JOUR
T1 - New Insights of Graphite Anode Stability in Rechargeable Batteries: Li-Ion Coordination Structures Prevail over Solid Electrolyte Interphases
AU - Ming, Jun
AU - Cao, Zhen
AU - Wahyudi, Wandi
AU - Li, Mengliu
AU - Kumar, Pushpendra
AU - Wu, Yingqiang
AU - Hwang, Jang-Yeon
AU - Hedhili, Mohamed N.
AU - Cavallo, Luigi
AU - Sun, Yang-Kook
AU - Li, Lain-Jong
N1 - KAUST Repository Item: Exported on 2020-04-23
Acknowledgements: The research was supported by KAUST. The simulations were performed on the KAUST supercomputer.
PY - 2018/1/10
Y1 - 2018/1/10
N2 - Graphite anodes are not stable in most noncarbonate solvents (e.g., ether, sulfoxide, sulfone) upon Li ion intercalation, known as an urgent issue in present Li ions and next-generation Li–S and Li–O2 batteries for storage of Li ions within the anode for safety features. The solid electrolyte interphase (SEI) is commonly believed to be decisive for stabilizing the graphite anode. However, here we find that the solvation structure of the Li ions, determined by the electrolyte composition including lithium salts, solvents, and additives, plays a more dominant role than SEI in graphite anode stability. The Li ion intercalation desired for battery operation competes with the undesired Li+–solvent co-insertion, leading to graphite exfoliation. The increase in organic lithium salt LiN(SO2CF3)2 concentration or, more effectively, the addition of LiNO3 lowers the interaction strength between Li+ and solvents, suppressing the graphite exfoliation caused by Li+–solvent co-insertion. Our findings refresh the knowledge of the well-known SEI for graphite stability in metal ion batteries and also provide new guidelines for electrolyte systems to achieve reliable and safe Li–S full batteries.
AB - Graphite anodes are not stable in most noncarbonate solvents (e.g., ether, sulfoxide, sulfone) upon Li ion intercalation, known as an urgent issue in present Li ions and next-generation Li–S and Li–O2 batteries for storage of Li ions within the anode for safety features. The solid electrolyte interphase (SEI) is commonly believed to be decisive for stabilizing the graphite anode. However, here we find that the solvation structure of the Li ions, determined by the electrolyte composition including lithium salts, solvents, and additives, plays a more dominant role than SEI in graphite anode stability. The Li ion intercalation desired for battery operation competes with the undesired Li+–solvent co-insertion, leading to graphite exfoliation. The increase in organic lithium salt LiN(SO2CF3)2 concentration or, more effectively, the addition of LiNO3 lowers the interaction strength between Li+ and solvents, suppressing the graphite exfoliation caused by Li+–solvent co-insertion. Our findings refresh the knowledge of the well-known SEI for graphite stability in metal ion batteries and also provide new guidelines for electrolyte systems to achieve reliable and safe Li–S full batteries.
UR - http://hdl.handle.net/10754/626975
UR - http://pubs.acs.org/doi/10.1021/acsenergylett.7b01177
UR - http://www.scopus.com/inward/record.url?scp=85041850813&partnerID=8YFLogxK
U2 - 10.1021/acsenergylett.7b01177
DO - 10.1021/acsenergylett.7b01177
M3 - Article
AN - SCOPUS:85041850813
VL - 3
SP - 335
EP - 340
JO - ACS Energy Letters
JF - ACS Energy Letters
SN - 2380-8195
IS - 2
ER -