Closure to “Discussion of ‘High Rate Discharge Characteristics of Li / SOCl2 Cells’ [K. A. Klinedinst and M. J. Domeniconi (pp. 539–544, Vol. 127, No. 3)]”

Self Cite

Molecular iodine has been found to be a powerful catalyst for the electroreduction of thionyl chloride in lithium anode cells. The I2 and SOC12 apparently function as a redox electrode, the SOC12 serving as a chemical regenerant for the molecular iodine which is reduced at the porous carbon cathode. Similar behavior is observed with Br2 in SQC12-based electro~ lytes. Because solid products form via chemical steps occurring subsequent to the electroreduction of the halogen, they tend not to block the cathode surface sites which remain active for the continued reduction of the chemically regenerated halogen.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 150.135.239.97 Downloaded on 2015-05-27 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 150.135.239.97 Downloaded on 2015-05-27 to IP ABSTRACTA rigorous technique of analyzing impedance data for systems which have convective Warburg impedance elements in them has been developed. In particular, a rotating disk electrode system was analyzed, by solving the applicable transient convective diffusion equation numerically. The numerical solution was used to find nonlinear least squares parameters to fit an impedance data set, over the entire frequency range. In this manner the diffusion coefficient and other physical parameters of the system were determined without any assumption about electrode area, solution concentration, or kinetics. The shortcomings of the conventional techniques to evaluate physical parameters from impedance data have been overcome.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 150.135.239.97 Downloaded on 2015-05-27 to IP

Section: Resultsmentioning

confidence: 99%

The Electrocatalysis of Oxyhalide Reduction by Dissolved Halogens in Lithium Anode Cells

Klinedinst¹

1990

Self Cite

“…The data were fit by using equivalent circuits and a nonlinear squares fitting program developed by Macdonald puted that a virgin BCX cell contains 1.2 Ah BrC1, 0.6 Ah Br2, and 0.6 Ah C12. The discharge of the BrC1 in the cell proceeds through the reductions of C12, Br2, and BrC1 ~2 C12 + 2e --> 2C1 at -3.8 V [2] 2BrC1 + 2e---> 2C1-+ Br2 at -3.6 V [3] BrCl+2e---->Br +C1-at -3.6V [4] Br2 + 2e--> 2Br-at -3.6 V [5] Also, Li § reacts with Br-to form LiBr which further reacts with SOCI~ to form S, Br~, SO~, and LiC1. The S then reacts with Br~ forming S2Br..,.…”

Section: Methodsmentioning

confidence: 99%

Impedance Spectroscopy as a Nondestructive Health Interrogation Tool for Lithium‐BCX Cells

Popov¹,

Zhang²,

Darcy

et al. 1993

The objective of this investigation was to study the growth of thick passivating layers on the Li anode in Li/BCX false(normalLi/SOCl2+normalBrClfalse) cells which were stored for a period of 3 years. Impedance spectroscopy and equivalent circuit models were used to determine characterizing parameters for these cells. The equivalent circuit used for virgin cells includes a faradic contribution and diffusion of the electroactive species. The equivalent circuit for batteries stored 1 or 2 years includes the impedance of a metal/passive film interface, the resistance of the film, and the impedance of the passivating film/electrolyte interface. The equivalent circuit used for batteries stored for 3 years accounts for cathodic contributions in the overall impedance spectrum.

“…In summary, the six governing equations for the separator are Eq. [24], [40], [42], [45], [46], and [47]. Researchers (32)(33)(34)(35) believe that the film passivates the Li and inhibits the mass transport of SOC12 to the Li surface.…”

Section: C)e Solid Phases Sikvimentioning

confidence: 99%

A Mathematical Model of a Lithium/Thionyl Chloride Primary Cell

Evans

Nguyen

White

1989

A one-dimensional mathematical model for the lithium/thionyl chloride, primary cell has been developed to investigate methods of improving its performance and safety. The model includes many of the components of a typical lithium/ thionyl chloride cell such as the porous lithium chloride film which forms on the lithium anode surface. The governing equations are formulated from fundamental conservation laws using porous electrode theory and concentrated solution theory. The model is used to predict one-dimensional, time dependent profiles of concentration, porosity, current, and potential as well as cell temperature and voltage. When a certain discharge rate is required, the model can be used to determine the design criteria and operating variables which yield high cell capacities. Model predictions can be used to establish operational and design limits within which the thermal runaway problem, inherent in these cells, can be avoided.The lithium/thionyl chloride (Li/SOC12) cell is an attractive primary energy source because of its high energy density (1, 2). However, researchers have observed that the Li/SOCI~ cell is a serious safety hazard under certain conditions (2). High discharge rates and high temperatures promote thermal runaway which can result in the venting *Electrochemical Society Student Member. **Electrochemical Society Active Member.of toxic gases and explosion. A mathematical model of this battery has been developed to investigate the operational and design characteristics which can be adjusted to yield efficient, yet acceptably safe Li/SOC12 cells.