TY - JOUR
T1 - Plastic Crystals Utilising Small Ammonium Cations and Sulfonylimide Anions as Electrolytes for Lithium Batteries
AU - Yunis, Ruhamah
AU - Al-Masri, Danah
AU - Hollenkamp, Anthony F.
AU - Doherty, Cara M.
AU - Zhu, Haijin
AU - Pringle, Jennifer M.
N1 - Publisher Copyright:
© 2020 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited.
PY - 2020/1/5
Y1 - 2020/1/5
N2 - Organic ionic plastic crystals (OIPCs) are increasingly promising as a class of solid-state electrolyte for developing safer lithium batteries. However, their advancement relies on expanding the range of well-characterised cation/anion combinations. Here, we report the synthesis and characterization of OIPCs utilising small ammonium cations tetramethylammonium ([N1111]+), triethylmethylammonium ([N1222]+) and tetraethylammonium ([N2222]+), chosen to encourage significant rotational and translational motion, with the charge-diffuse and electrochemically stable bis(fluorosulfonyl)imide ([FSI]) and bis(trifluoromethanesulfonyl)imide ([NTf2]) anions. To investigate the physico-chemical properties of the OIPCs, the free volume was measured by positron annihilation spectroscopy (PALS) and correlated with the ionic conductivity and thermal analysis (DSC). Solid-state NMR analysis of the salts, is also reported. The salts with the less symmetric cation, [N1222][FSI] and [N1222][NTf2], were identified as the most promising electrolyte materials, and thus the electrochemical properties after mixing with 10 and 90 mol% lithium bis(fluorosulfonyl)imide (LiFSI) or lithium bis(trifluoromethanesulfonyl)imide (LiNTf2), respectively, were investigated. This study demonstrates the efficacy of these OIPC materials as new quasi-solid state electrolytes with advantageous properties such as high conductivity, good thermal and electrochemical properties, the ability to incorporate high lithium salt concentrations and support efficient lithium electrochemistry.
AB - Organic ionic plastic crystals (OIPCs) are increasingly promising as a class of solid-state electrolyte for developing safer lithium batteries. However, their advancement relies on expanding the range of well-characterised cation/anion combinations. Here, we report the synthesis and characterization of OIPCs utilising small ammonium cations tetramethylammonium ([N1111]+), triethylmethylammonium ([N1222]+) and tetraethylammonium ([N2222]+), chosen to encourage significant rotational and translational motion, with the charge-diffuse and electrochemically stable bis(fluorosulfonyl)imide ([FSI]) and bis(trifluoromethanesulfonyl)imide ([NTf2]) anions. To investigate the physico-chemical properties of the OIPCs, the free volume was measured by positron annihilation spectroscopy (PALS) and correlated with the ionic conductivity and thermal analysis (DSC). Solid-state NMR analysis of the salts, is also reported. The salts with the less symmetric cation, [N1222][FSI] and [N1222][NTf2], were identified as the most promising electrolyte materials, and thus the electrochemical properties after mixing with 10 and 90 mol% lithium bis(fluorosulfonyl)imide (LiFSI) or lithium bis(trifluoromethanesulfonyl)imide (LiNTf2), respectively, were investigated. This study demonstrates the efficacy of these OIPC materials as new quasi-solid state electrolytes with advantageous properties such as high conductivity, good thermal and electrochemical properties, the ability to incorporate high lithium salt concentrations and support efficient lithium electrochemistry.
UR - http://www.scopus.com/inward/record.url?scp=85082382997&partnerID=8YFLogxK
U2 - 10.1149/1945-7111/ab76a2
DO - 10.1149/1945-7111/ab76a2
M3 - 文章
AN - SCOPUS:85082382997
SN - 0013-4651
VL - 167
JO - Journal of the Electrochemical Society
JF - Journal of the Electrochemical Society
IS - 7
M1 - 070529
ER -