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Rehm, Raymond

Publications and source records attributed to Rehm, Raymond.

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

Building on the Past - Looking to the Future. Part 2: A Focus on Expanding Horizons

The history of space endeavors stretches far from the first liquid-fueled rocket created by the father of modern rocketry, Robert Goddard, in 1926 and will certainly extend far beyond the construction of the International Space Station (ISS) scheduled to be complete with the addition of the Permanent Multipurpose Module on STS-133/ULF5. National Aeronautics and Space Administration (NASA) and the ISS International Partners (IPs) will be the unrelenting venue used to satisfy the curiosities of man as we seek an understanding of space through various experiments (also referred to as payloads) conducted in microgravity. The NASA Payload Safety Review Panel (PSRP) continues to serve as the lead for the review and assessment of payload hardware to assure facility and crew safety. This is the second in a series of papers and presentations that illustrate challenges and lessons learned in the areas of communication, safety requirements, and processes which have been vital to the PSRP.

Nash, Sally K.↗
NASA NTRS2002

Evaluation of Cycle Life and Characterization of YTP 45 Ah Li-Ion Battery for EMU

Li-ion batteries, with longer cycle life and higher energy density features, are now more and more attractive and applied in multiple fields. The YTP 45 Ah Li-ion battery has been evaluated here and may be employed in EMU in the future. Evaluations were on: (1) Cycle life tests - 500 cycles total (completed 40 cycles in simulated shuttle use mode and 460 cycles in an accelerated use mode, and recorded differential voltage of individual cell in battery); (2) Characterization test - discharge capacity measurement in environment temperature of -10, 25, 50 C before and after 500 cycles; and (3) Thermal testing - charge and discharge at 50 C and -10 C before and after 500 cycles. The battery showed less than a 9% drop of initial discharge capacity and energy within 500 cycles with 475 cycles 59% DOD plus 25 cycles 100% DOD. The EOD voltage ranged from 16.0 to 18.0 V, which fits the requirement for operating the EMU.

Deng, Yi↗
NASA NTRS2002

Performance and Safety Tests on Samsung 18650 Li-ion Cells: Two Cell Designs

In order to meet the applications for space shuttle in future, two types of Samsung cells, with capacity 1800 mAh and 2000 mAh, have been investigated. The studies focused on: (1) Performance tests: completed 250 cycles at various combinations of charge/discharge C rates and discharge capacity measurements at various temperatures; and (2) Safety tests: overcharge and overdischarge, heat abuse, short circuit, internal and external short, and vibration, vacuum, and drop tests

Deng, Yi↗
NASA NTRS2001

Li-ion EMU Battery Testing

A 45Ah Lithium ion (Li-Ion) battery comprised of 5 Yardney prismatic cells was evaluated to replace the silver-zinc cells in the Extra-vehicular Mobility Unit (EMU). Tests determined that the five cell battery can meet the mission objective of 500 duty cycles and maintain a minimum voltage of 16.0 V without an individual cell voltage dropping below 3.0V. Forty real time cycles were conducted to develop BOL trend data. Decision to switch to accelerated cycling for the remaining 460 cycles was made since Real Time cycling requires 1 day/cycle. Conclusions indicate that battery replacement would indeed be prudent.

Rehm, Raymond↗
NASA NTRS1992

Nickel hydrogen cell design: A designer's aspect

Information is given to give insight into the methodology of nickel hydrogen cell design and the decipherment of the battery cell reference guide that was distributed to many of Gates Energy Products' customers. Cell design, stacking design, charge capacity, and dynamic response are discussed in general terms.

Rehm, Raymond↗