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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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A Battery Certification Testbed for Small Satellite Missions
A battery pack consisting of standard cylindrical 18650 lithium-ion cells has been chosen for small satellite missions based on previous flight heritage and compliance with NASA battery safety requirements. However, for batteries that transit through the International Space Station (ISS), additional certification tests are required for individual cells as well as the battery packs. In this manuscript, we discuss the development of generalized testbeds for testing and certifying different types of batteries critical to small satellite missions. Test procedures developed and executed for this certification effort include: a detailed physical inspection before and after experiments; electrical cycling characterization at the cell and pack levels; battery-pack overcharge, over-discharge, external short testing; battery-pack vacuum leak and vibration testing. The overall goals of these certification procedures are to conform to requirements set forth by the agency and identify unique safety hazards. The testbeds, procedures, and experimental results are discussed for batteries chosen for small satellite missions to be launched from the ISS.
Safe, High Specific Energy & Power Lithium Ion Cell Designs
The higher energy content (265 Wh/kg, 725 Wh/L) of the newer cell designs from LG, Panasonic, and Samsung have made them susceptible to side wall ruptures (SWR) during thermal runaway, rather than venting through the intended vent path in the cell header. This is also due to higher reaction kinetics of the electrochemistry, thinner can walls, tight crimp enclosure of the cell header, and inadequate flow rate through the header vent. This effort determined that bottom vents and thicker cell can walls both are necessary for reducing the risk of SWR. Compelling evidence was obtained using novel test methods that included an on-demand internal short circuit device, high speed X-ray videography, and cell thermal runaway calorimetry.
Prognostics and Health Monitoring: Application to Electric Vehicles
As more and more electric vehicles emerge in our daily operation progressively, a very critical challenge lies in the prediction of remaining driving-time distance (for cars) or flying time-distance (for aircraft). This information is important, particularly in the case of unmanned vehicles, because such vehicles can become self-aware, autonomously compute its own capabilities, and identify how to best plan and successfully complete vehicular missions safely. In case of electric aircrafts, computing remaining flying time is also safety-critical, since an aircraft that runs out of power (battery charge) while in the air will eventually lose control leading to catastrophe. In order to tackle and solve the prediction problem, it is essential to have awareness of the current state and health of the system, especially since it is necessary to perform condition-based predictions. To be able to predict the future state of the system, it is also required to possess knowledge of the current and future operations of the vehicle.
Metallized Plastic Current Collectors
Metallized plastic current collectors are an innovation patented by the Soteria Battery Innovation Group with the promise of isolating active material involved in an internal short by vaporizing and isolating the short from the rest of the cell electrode jellyroll or stack. Partnering with NREL, UCL, Coulometrics, and Soteria, NASA is leading a research effort into demonstrating the merits and understanding the phenomena of this safety innovation using prototype 18650 cylindrical cells vs control cells with standard metal foil current collectors. Cells with and without the plastic collector, with and without the on-demand internal short circuit device, and with polymer or cellulose separators were made. Safety evaluations were done with driving cells into thermal runaway (TR) with thermal and nail penetration triggers while inside our TR calorimeter and with ultra high speed X-ray videography provided at Synchrotrons. Preliminary results suggests that the thermally unstable plastic current collector innovation has great promise for preventing TR or reducing the severity of the TR output.
Cycling and Low Temperature Performance of Li Ion Cells
Lithium-ion cells, of DD and D size, are being developed under a contract with the USAF for NASA's Mars Rover Missions. The cells contain spirally wound electrodes of LiNi02 positive electrode material and graphite anode in cylindrical stainless steel hardware.
Alkyl Pyrocarbonate Electrolyte Additives for Performance Enhancement of Li Ion Cells
Lithium ion rechargable batteries are being developed for various aerospace applications under a NASA-DoD interagency program. In this paper, we report the beneficial effect of using alkyl pyrocarbonates as electrolyte additives to improve the low temperature performance of lithium ion cells.
Performance Characteristics of Yardney Lithium-Ion Cells for the Mars 2001 Lander Application
This paper will describe the Mars 2001 Lander mission battery requirements and will contain results of the cell testing conducted to-date in support of the mission.
Battery Relevant Cell Side Wall Rupture Characterization
The propensity for a cell design to experience can side wall rupture (SWR) during thermal runaway is highly influenced by how a battery design mechanically constrains its cells. Testing cells while unsupported has been found to yield false negative results that don't represent this risk in a battery configuration. This talk addresses how to verify the adequacy of battery design measures used to control SWR and how to get results relevant, accurate, and statistically defendable for a proposed battery design.
Lunar Power Hibernation for Surviving the Lunar Night
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Battery Relevant Cell Side Wall Rupture Characterizations
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Investigating the Ability of Plastic Current Collectors to Isolate Internal Shorts in High Energy Cells
Determine how these plastic current collectors work and can they obviate the battery design burden for achieving passive propagation resistance.
Investigating the Ability of Plastic Current Collectors to Isolate Internal Defects in High Energy Cells
Determine how these plastic current collectors work and can they obviate the battery design burden for achieving passive propagation resistance?
An Accelerated Life Testing Dataset for Lithium-Ion Batteries With Constant and Variable Loading Conditions
The dataset repository is organized into three main folders, each containing one group of life cycled battery packs. Within each folder individual battery packs own their dedicated csv file for continuous data logging, which are named with their respective battery pack number. The folders are named: - regular_alt_batteries: Containing one csv file for each battery pack cycled at the same load level or load range throughout lifetime - recommissioned_batteries: Containing one csv file for each battery pack cycled at different load levels at varying life stages - second_life_batteries: Containing one csv file for each second life battery pack cycled at constant current througout the second life
Investigating the Ability of Plastic Current Collectors to Isolate Internal Defects in High Energy Cells
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Investigating the Ability of Plastic Current Collectors to Tolerate Nail Penetration in High Energy Cells
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Investigating Plastic Current Correctors for Isolating Internal Shorts in High Energy Cells
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Thermal Runaway Comparison Between Pressurized Gas vs Standard Eletrolyte in 2.7Ah 18650 Cells
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