NanoRacks-Riverside Christian Schools-Battery Performance Experiment (NanoRacks-RCS-Battery Performance ) - 07.29.14
ISS Science for Everyone
Science Objectives for Everyone
Long-term space travel requires the use of medical and other devices that rely on small coin-cell size batteries as their power source. NanoRacks–Riverside Christian Schools–Battery Performance Experiment (NanoRacks–RCS–Battery Performance) provides insight as to whether microgravity has an impact on the performance of current battery technology. Specifically, does microgravity increase or decrease the useful life of a battery as compared to what is normally experienced in Earth gravity.
Science Results for Everyone
OpNom NanoRacks Module-21
NanoRacks, LLC, Houston, TX, United States
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
National Laboratory Education (NLE)
ISS Expedition Duration
September 2012 - September 2013
Previous ISS Missions
• NanoRacks–Riverside Christian Schools–Battery Performance Experiment (NanoRacks–RCS–Battery Performance) provides some insight as to whether current battery technology can meet the power needs of small battery powered medical devices that are required for long-term space travel, or if new batteries need to be developed for these devices. In addition, it provides insight into the usability of manufacturer testing as a predictor of battery performance in the Space environment.
• Battery performance in microgravity and Earth gravity is measured and compared to determine if the battery performance in space falls within the normal variation of the battery performances measured on Earth as well as how it compares to manufacturer test results.
• NanoRacks–RCS–Battery Performance provides an initial step in the decision process as to whether or not new battery technology is required for small medical devices during long-range space travel as well as insight into the usability of manufacturer testing as a performance predictor in space.
NanoRacks–Riverside Christian Schools–Battery Performance Experiment (NanoRacks–RCS–Battery Performance) consists of two circuits: a Battery Enable circuit and a Battery Test circuit. The Battery Enable circuit is a simple transistor switching circuit that provides sufficient current to energize the Battery Test Enable Relay and turn on the “Enable LED”. Once energized, the Test Enable Relay connects the resistive load to the battery, drawing current from the battery until its total power is expended over time.
The battery selected for test is the Panasonic BR1225A, a small lithium coin cell battery used in small medical-like electronic devices. The small resistive load that is used to “drain” battery power (less than 5% of original capability) is composed of two precision trim pots whose load resistance is consistent with those used by the manufacturer during their testing as documented in technical specification data sheets. Expected time duration to drain the battery is 10-12 days. Battery voltage, battery current, enclosure temperature and humidity, MicroLab source voltages, and time are among the data recorded on a periodic basis. Onboard MicroLab A/D convertors are used to convert analog data to digital data for recording purposes. A snapshot of data is recorded every 10 minutes, and output to the NanoLab Master Controller on an hourly basis.
Similar tests are conducted in the “Ground” environment with multiple batteries for the purpose of comparison of performance of the coin cell in microgravity. “Time to drain” the battery as well as total “mAh” (milliampere-hour) capacity will serve as the primary data to be evaluated, ascertaining whether or not the performance in microgravity falls within the range of performances of the batteries tested in the Earth gravity environment.
Long-range space travel to Mars and beyond will ultimately require medical devices that use very small batteries. NanoRacks–RCS Battery Performance provides insight into the predictability of battery performance in space based on manufacturing testing, and how current battery technology can meet the power needs of those devices.
NanoRacks–RCS Battery Performance gives the Riverside Christian students the opportunity to take their classroom math and science theory and move it beyond the laboratory and into a real-world scientific experiment experience in space. In addition, it gives them the opportunity to see what engineering in the technical community is really all about.
NanoRacks Module-21 is completely autonomous and only requires installation and removal. NanoRacks Module–21 returns on 33S.
Crew interaction with Module-21 is limited to transferring the NanoRacks locker Insert from the launch vehicle to the ISS, installation and activation of the NanoRacks Frames into the EXPRESS Rack Locker, cleaning of the air inlet filter (as necessary), and data retrieval (as needed) during the mission.
The RCS Payload Board components for the NanoRacks–Riverside Christian Schools–Battery Performance Experiment (NanoRacks–RCS–Battery Performance) on the right side show the coin cell battery and the precision trim pots that are used for the battery load. The vertical wall and the small horizontal tubular device which is a valve, support the Bacteria Growth experiment which is the second experiment housed in the single RCS MicroLab. The additional onboard circuitry supports control, power monitoring, enclosure lighting for photographs, and temperature sensing. Image courtesy of Riverside Christian Schools.
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Danielle Nelson, Mackenzie Williams, and Megan Holmes, Riverside Christian Schools, are making circuit measurements to ensure proper connectivity before power is applied to the circuits for the NanoRacks–Riverside Christian Schools–Battery Performance Experiment (NanoRacks –RCS–Battery Performance). Image courtesy of Riverside Christian Schools.
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Riverside Christian Schools student Elise Schaefer assembles the second generation RCS payload board, soldering in place, one of the 39 components on the payload board. The Payload board was designed using the ExpressSCH and ExpressPCB CAD programs. Elise took the system level schematic diagram and did the component layout and trace interconnectivity of components for the Payload board using the ExpressPCB CAD program. Image courtesy of Riverside Christian Schools.
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