M. Ue
Dec 1, 1994
Citations
4
Influential Citations
412
Citations
Quality indicators
Journal
Journal of The Electrochemical Society
Abstract
Propylene carbonate (PC) and [gamma]-butyrolactone (GBL) are important dipolar aprotic solvents used for nonaqueous electrolytes in high energy lithium batteries, aluminum electrolytic capacitors, and electrical double-layer capacitors. The conductivities of lithium and quaternary ammonium salts have been measured in propylene carbonate and [gamma]-butyrolactone at 25 C over the concentration range of 10[sup [minus]2] to 10[sup [minus]3] mol dm[sup [minus]3]. The limiting molar conductivities and the ionic association constants were calculated by the expanded Fuoss-Hsia equation. The mobility of anions in both solvents decreased in the following order: BF[sub 4][sup [minus]] > ClO[sub 4][sup [minus]] > PF[sub 6][sup [minus]] > CF[sub 3]SO[sub 3][sup [minus]] > (CF[sub 3]SO[sub 2])[sub 2]N[sup [minus]] > C[sub 4]F[sub 9]SO[sub 3][sup [minus]] > BPh[sub 4][sup [minus]]. The association constants increased in the following order: Li(CF[sub 3]SO[sub 2])[sub 2]N, LiAsF[sub 6] < LiAsF[sub 6] < LiClO[sub 4] < LiBF[sub 4] < LiC[sub 4]F[sub 9]SO[sub 3] < LiCF[sub 3]SO[sub 3], while those of the corresponding tetraethylammonium salts were leveled by electrostatic shielding effect of alkyl groups. These results were correlated with ionic radii obtained by MM2 calculation.