An Investigation of the Volume Change Associated with Discharge of Lithium/Iodine Batteries via Holographic Interferometric Techniques

• Published in: Journal of the Electrochemical Society 1986-01, Vol.133 (1), p.1-5
• Main Authors: Phillips, L. C., Kelly, R. G., Wagner, J. W., Moran, P. J.
• Format: Article
• Language: English
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1.2108523

As part of an effort to delineate the rate-limiting mechanism in Li/I sub(2) (P2VP) batteries with pelletized cathodes, a holographic interferometric technique has been used to study the volume change associated with the high rate discharge of these cells. This technique gives information on the changes in the thickness of the hermetically sealed package, from which insights concerning the uniformity of, an the volume change associated with, high rate discharge can be gleaned. Cells discharged across 1.5, 5, and 10k Omega have been studied. The results indicate that early in discharge these cells expand in a nonuniform manner. This demonstrates that the assumptions previously used to calculate the expected volume change upon discharge for cells with cooked-and-cast cathodes, including the idea that the LiI layer formed does so in a uniform manner with theoretical atomic density, cannot be applied to cells with pelletized cathodes.