Xm. Wang et al., Electrochemical properties of tetrahydropyran-based ternary electrolytes for 4 V lithium metal rechargeable batteries, ELECTR ACT, 46(6), 2001, pp. 813-819
In order to improve low-temperature performance of ethylene carbonate (EC)
+ tetrahydropyran (THP) (5:5) electrolyte with 1 mol dm(-3) lithium bisperf
luoroethylsulfonyl imide (LiN(SO2C2F5)(3) as solute, propylene carbonate (P
C) solvent was mixed with this electrolyte. It was found that the electroch
emical properties of the resultant ternary electrolytes depended strongly o
n the solvent composition and 1 mol dm(-3) (LiN(SO2C2F5)(2))/EC + PC + THP
(3:3:4) electrolyte had not only promising freezing point of -36 degreesC b
ut also high lithium cycling efficiency of 95.2%. Furthermore, lithium cycl
ing efficiency was improved to 99.0% by decreasing lithium deposition curre
nt density to 0.2 mA cm(-2). At the temperature ranging from 25 to -10 degr
eesC, Li/LiMn2O4 coin cell with 1 mol dm(-3) (LiN(SO2C2F5)(2))/ EC + PC + T
HP (3:3:4) electrolyte showed the satisfactory cycling performance. Thermal
tests further disclosed that this ternary electrolyte showed good thermal
stability even with the existence of lithium metal. (C) 2001 Elsevier Scien
ce Ltd. All rights reserved.