J.S. Gnanaraj^a, E. Zinigrad^a, L. Asraf^a, M. Sprecher^a, H.E. Gottlieb^a,W. Geissler ^b, M. Schmidt^b, D. Aurbach^a,* ^aDepartment of Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel b Merck KGaA, D-64293 Darmstadt, Germany

Received 4 August 2003; received in revised form 27 August 2003; accepted 27 August 2003

Published online: 2 October 2003

In the ARC tests, two milliliters of solution was placed in a titanium spherical bomb (8 ml volume) in a vacuum glove box and were transferred to the calorimeter under a highly purified Ar atmosphere. The solutions were heated to between 40 and 350 C with 5 C increments at the rate of 2 C/min in the search for selfheating at the sensitivity threshold of 0.02 C/min. The detailed experimental procedure is cited elsewhere [14].After the ARC experiments were performed, the gas was released through a high-pressure valve specially designed for this purpose and could be analyzed by FTIR and MS.The residual liquid phase was also analyzed. DSC tests were carried out at a heating rate of 2 C/min in the temperature range of 30–400 C. High-pressure gold plated stainless crucibles, 30 ll in volume, were used in the DSC tests. The crucibles were filled by 2 ll of a sample and were closed in the glove box. We used 1H,13C, 31P and 19F NMR (instrumentation from Bruker Inc.), GCMS (instrumentation from Finnigan Inc.) and FTIR (Magna 860 spectrometer from Nicolet Inc.) to analyze the reaction products at different reaction stages.

The anodes were composed of synthetic graphite (KS-6) from Timrex Inc. (average particle size ca. 6 lm,90 wt%), PVdF binder (10 wt%) from Solvey Inc., and copper foil current collectors. Slurries containing the active mass and the binder were prepared using Nmethyl pyrrolidone (Fluka Inc.) and were coated on copper foil current collectors. The electrodes were dried in an oven at 140 C and then were transferred to the glove boxes. Long-term cycling tests for graphite electrodes were performed in two-electrode standard coin-type cells (Model 2032, NRC Canada, / 19 mm),separated by a porous polypropylene membrane (Celgard Inc.). All the work was performed under a highly purified argon atmosphere in standard glove boxes from VAC Inc. The coin-type cells were hermetically sealed in a dry air-filled glove box using the Coin Cell Crimper .