Li-7 NMR studies have been carried out on some vanadium bronzes of interest as cathodes in rechargeable Li cells. Li0.63NaV3O8, amorphous LiV3O8 (both prepared at low temperature), Li0.59NaV3O8 and crystalline LiV3O8 (both prepared at high temperature) have been investigated by measuring linewidth, spin-lattice and spin-spin relaxation times. For the first three samples above, it was possible to calculate the self-diffusion coefficients (10(-11) cm2 s-1 for the Na bronzes and 10(-9) cm2 s-1 for amorphous LiV3O8). These values are lower than those for the chemical diffusion coefficients measured by electrochemical techniques. This is explained by different contributions to the enhancement factor.
Comparison of Li+ transport in Na1+xV3O8 and Li1+xV3O8 by 7Li NMR investigations / G., Wang; J., Roos; D., Brinkmann; Pasquali, Mauro; G., Pistoia. - In: JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS. - ISSN 0022-3697. - STAMPA. - 54:(1993), pp. 851-855. [10.1016/0022-3697(93)90255-P]
Comparison of Li+ transport in Na1+xV3O8 and Li1+xV3O8 by 7Li NMR investigations.
PASQUALI, Mauro;
1993
Abstract
Li-7 NMR studies have been carried out on some vanadium bronzes of interest as cathodes in rechargeable Li cells. Li0.63NaV3O8, amorphous LiV3O8 (both prepared at low temperature), Li0.59NaV3O8 and crystalline LiV3O8 (both prepared at high temperature) have been investigated by measuring linewidth, spin-lattice and spin-spin relaxation times. For the first three samples above, it was possible to calculate the self-diffusion coefficients (10(-11) cm2 s-1 for the Na bronzes and 10(-9) cm2 s-1 for amorphous LiV3O8). These values are lower than those for the chemical diffusion coefficients measured by electrochemical techniques. This is explained by different contributions to the enhancement factor.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
