Lithium self-diffusivity

Mechanisms of micellar reactions have been studied by a kinetic study of the state of the proton at the surface of dodecyl sulfate micelles [191]. Surface diffusion constants of Ni(II) on a sodium dodecyl sulfate micelle were studied by electron spin resonance (ESR). The lateral diffusion constant of Ni(II) was found to be three orders of magnitude less than that in ordinary aqueous solutions [192]. Migration and self-diffusion coefficients of divalent counterions in micellar solutions containing monovalent counterions were studied for solutions of Be2+ in lithium dodecyl sulfate and for solutions of Ca2+ in sodium dodecyl sulfate [193]. The structural disposition of the porphyrin complex and the conformation of the surfactant molecules inside the micellar cavity was studied by NMR on aqueous sodium dodecyl sulfate micelles [194]. 

Quite extraordinary diffusion coefficients of impurities from other parts of the Periodic Table are found, and especially in the important case of lithium or copper diffusion, where the enhancement over self-diffusion is by six to eight orders of magnitude. This indicates that these atoms do not form part of the sp3 network in the structure, but more closely resemble separate atoms in the sp3 matrix. 

Hayamizu and Akiba measured self-diffusion coefficients of lithium ion, anion and solvent in the electrolytes for lithium batteries. The self-association of some anions is discussed. Sekhon et u/. investigated the diffusive motion of cations and anions in polyethylene oxide based polymer electrolytes. Translational motion was found above Tg. 

S. Tsuzuki, K. Hayamizu, S. Seki, J. Phys. Chem. B 2010, 114, 16329-16336. Origin of the low viscosity of [emim][(FS02)2N] ionic Uquid and its lithium salt mixture Experimental and theoretical study of self-diffusion coefficients, conductivities, and intermolecular interactions. 

Aihara, Y Bando, X Nakagawa, H. Yoshida, H. Hayamizu, K. Akiba, E. Price, W. S., Ion Transport Properties of Six Lithium Salts Dissolved in Gamma-Butyrolactone Studied by Self-Diffusion and Ionic Conductivity Measurements. J. Electrochem. Soc. 2004,151, A119-A122. 

Lindman, B., Payal, M.-C., Kamenka, N., Rymden, R., and Stilbs, R, Micelle formation of anionic and cationic surfactants from Fourier transform proton and lithium-7 nuclear magnetic resonance and tracer self-diffusion studies, J. Phys. Chem., 88, 5048, 1984. 

Aihara Y et al (2004) Ion transport properties of six lithium salts dissolved in gamma-butyrolactone studied by self-diffusion and ionic conductivity measurements. J Electrochem Soc 151 A119... 

The self-diffusion of lithium in molten Li2BeF4 was measured using the capillary... 

The self-diffusion of lithium in a molten LiF-NaF-KF (46.5 11.5 42.0mol%) eutectic mixture was measured by using the capillary reservoir technique and the tracer, Li. The self-diffusion at 480 to 663C was described by ... 

Saito Y, Yamamoto H, Nakamura O, Kageyama H, Ishikawa H, Miyoshi T, Matsuoka M (1999) Determination of ionic self-diffusion coefficients of lithium electrolytes using the pulsed field gradient NMR. J Power Sources 81-82 772-776... 

The coulombic efficiency of Li-Al/FeS cells is controlled by the lithium activity of the negative electrode and the rate at which dissolved lithium can diffuse across the separator to the positive electrode. Typically this rate is only 0.1 to 0.2 mA/cm at 425°C. This low self-discharge rate leads to high coulombic efficiency. Similarly, the low impedance of bipolar cells (0.5 to 0.7 ft cm ) leads to high voltaic efficiency. Overall the major source of inefficiency is the heat loss associated with high-temperature operation. Development of a highly efficient thermal enclosure is necessary for aU high-temperature batteries. 

On the other hand, for measurements done at constant temperature (850 °C), Dp and Dpi continually decrease monotonously with the addition of CaF2. These results clearly show the effects of the composition and of the temperature on the self-diffusion. Such observations have been already described for fluorine self-diffusion coefficients in other fluoride systems [14,15]. Nevertheless, the fact that lithium is significantly affected by the composition was not seen in LiF-KF melts. Potassium and lithium cations have close ionic radii and have the same valence. Their ionic potentials corresponding to the polarizing strength of the ions... 

Figure 4.3.4 Self-diffusion coefficients of fluorine and lithium in molten FiF-CaF2 at 10°C above the liquidus temperature (m F LI) and at T = 850° C fD 0 Li) as a function of the composition...

The calculated viscosity, thermal conductivity and self-diffusion coefficients (the latter at 0.10 MPa) of nonionized monatomic lithium, sodium, potassium, rubidium and cesium vapors can be consulted for temperatures between 700 and 2000 K in Tables VIII to XII of the work of Fialho et al. (1993). 

Fig. 11. Evolution of the self-diffusion coefficients at 25°C for the solvent molecules (iH NMR) and the lithium cations ( Li NMR) in the LiTFSI/Pis-TFSI mixture samples as a function of the LiTFSI concentration (a), and in the LiPFa/Pis-TFSI mixture samples as a function of the LiPFe concentration (b).

Fig. 12. Evolution of the ratio of lithium and hydrogen self-diffusion coefficients as a function of either the nature or the amount of the added salt to P15-TFSI at 25°C.

Table 4. Self-diffusion coefficients, in m2.s-i, for molecular solvents and P15+ cation (fromiR NMR), as well as for the lithium cation (from Li NMR), in the presence of 1 M LiPFe.

Lenke R, Uelenhack W, Klemm A (1973) Self-diffusion in molten lithium chloride. Z Naturforsch 28A 881-884... 

Bossev et al. [141,142] studied the counterion effect on micellar systems formed by tetraethylammonium perfluorooctylsulfonate (TEAFOS) and lithium perfluorooctylsulfonate (LiFOS). H- and -NMR measurements of self-diffu-sion coefficients and chemical shifts showed that LiFOS, which forms spherical micelles, has a fast exchange rate. The TEA counterions induce a transformation to threadlike structures. As a result, the self-diffusion coefficient for TEAFOS is by a magnitude lower than that of LiFOS. 

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