Destructive physical analysis results of Ni/H2 cells cycled in LEO regimeSix 48-Ah individual pressure vessel (IPV) Ni/H2 cells containing 26 and 31 percent KOH electrolyte were life cycle tested in low earth orbit. All three cells containing 31 percent KOH failed (3729, 4165, and 11,355 cycles), while those with 26 percent KOH were cycled over 14,000 times in the continuing test. Destructive physical analysis (DPA) of the failed cells included visual inspections, measurements of electrode thickness, scanning electron microscopy, chemical analysis, and measurements of nickel electrode capacity in an electrolyte flooded cell. The cycling failure was due to a decrease of nickel electrode capacity. As possible causes of the capacity decrease, researchers observed electrode expansion, rupture, and corrosion of the nickel electrode substrate, active material redistribution, and accumulation of electrochemically undischargeable active material with cycling.
Document ID
19920068083
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Lim, Hong S. (NASA Lewis Research Center Cleveland, OH, United States)
Zelter, Gabriela R. (Hughes Aircraft Co. Torrance, CA, United States)
Smithrick, John J. (NASA Lewis Research Center Cleveland, OH, United States)
Hall, Stephen W. (U.S. Navy, Naval Weapons Support Center Crane, IN, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1991
Subject Category
Spacecraft Propulsion And Power
Meeting Information
Meeting: IECEC ''91: Intersociety Energy Conversion Engineering Conference