Analysis of Asbestos Uniformity

Following the production of a nickel hydrogen cell lot that gave quite poor performance during acceptance testing, a strip of asbestos was obtained from the roll used as separator in this cell lot. Tests reported herein on this asbestos material indicate that about half the width of the asbestos roll (in this specific location along its length) contains significantly higher quantities of a magnesium compound that exchanges hydroxide with KOH electrolyte, when compared with the other half of the roll width. Tests are indicated here that can be used to screen asbestos for such contamination prior to cell fabrication. It is possible that such reactions of the electrolyte with the asbestos could severely degrade cell performance. At present nickel hydrogen cell tests are under way using separator from each half of this roll to determine how cell performance correlates with the levels of contaminants observed. jg p.3