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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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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) Beyond Li-Ion: Technology to Enable Sustainable Electric Aviation

All-electric and hybrid electric aerovehicle concepts face numerous technical barriers prior to their introduction into the consumer marketplace in order to meet sustainable aviation goals. One of the primary barriers to overcome is developing an energy dense storage system capable of meeting the rigorous aerospace safety and performance criteria. Additionally, the electric aviation market requires that the batteries be fabricated in a sustainable manner with materials that are readily available and abundant within the U.S. to ensure there are no supply chain issues during manufacturing. The performance metrics to enable electric aviation are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. The hybrid cathode has been developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte has been used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This poster summarizes recent results from battery component optimization to scale-up production of full SABERS pouch cells.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRSDate not supplied

Solid-state battery designed for electric aviation

The demand for higher energy density batteries increases as the demand for portable electronic devices and electric automotive increases, as well as a variety of other applications requiring substantially higher power and energy than attainable with current lithium-ion capabilities which includes the areas of high performance vehicles, military applications, and electric aviation. However, the improvement of energy density is insufficient alone for enabling electric aviation when considering the high flammability and risk of thermal runaway inherent in current state-of-the-art liquid electrolytes. The development of high energy, high power, and safe batteries are required to enable hybrid and fully electric aircraft. Next generation chemistries such as lithium-sulfur provide high theoretical specific energy density suitable for electric aviation without as strict of volumetric requirements observed in the automotive industry. However, due to the phase transition during discharge where sulfur generates a series of soluble intermediate polysulfides, which are lost to the liquid electrolyte, cause detrimental side effects, and severely limit cycle life battery performance is severely reduced. Additionally, the low electrical conductivity of sulfur requires a large amount of inactive carbon dramatically increasing parasitic mass. The dissolution issue make sulfur a desirable candidate to pair with a solid-state electrolyte in order to avoid polysulfide dissolution and shuttling. In addition, inorganic solid-electrolytes have low flammability providing the improved safety required. Combining this chemistry with a solid-state electrolyte provides a path for achieving the energy and safety required for electric aviation. The development of scalable thin solid-state electrolytes paired with lithium-sulfur chemistry will be discussed and how their development will aid in enabling a unique application.

Donald A. Dornbusch↗
NASA NTRS2022

Powering the Future of Electric Aviation

Aviation is one of the largest contributors to climate change on this planet, responsible for nearly 5% of the global warming impact on Earth. As the aviation sector is projected to grow and as new aircraft are introduced, aviation’s impact on climate change will only increase. Without sustainable alternatives implemented in the near future, aviation could strongly contribute to making this planet uninhabitable. This paper examines the possibilities of electric aviation and other power sources in reducing the impact of aviation on climate change. Although there are many power sources for aircraft, electricity is the most effective and sustainable power source. Electric aviation, however, is still relatively new, and there are limitations with electric power, such as battery size, energy density, and charging. This paper dives deeper into the applications and factors to consider for the implementation of electric aircraft into the current society, as well as a potential solution to accelerate the process. Specifically, our research finds that hydrogen fuel cells, despite a few limitations, provide the amount of energy necessary to develop capable and sustainable electric aircraft in a manner that may be the most feasible.

electric aviation↗
NASA NTRSDate not supplied

Design Considerations for Practical Li-S Batteries for Electric Aviation

The development of high-energy, high-safety, and high-power batteries beyond electric automotive standards is critical for future electric aviation applications. Non-volatile solid-state electrolytes (SSE) offer many promising advantages over traditional flammable liquid electrolytes. Solid-state electrolytes may be an enabling technology for certain battery chemistries by preventing detrimental interactions with liquid electrolytes, for example prevention of the dissolution of intermediates in lithium-sulfur common in traditional liquid organic solvents. However, significant manufacturing challenges must be overcome before the adoption of such technology. This research was conducted to identify processing techniques for producing solid-state battery components with practical dimensions and weights for enabling high specific energy cells. Traditional research has identified a range of very high theoretical ionic conductivities but are impractical due to their instability or inability to be manufactured. Electrolytes explored in this study were produced as sulfide-polymer composites with densified thicknesses below 40 micron using a tape-casting technique and thermoplastic elastomer binder. The combination of high chemical compatibility and flexibility produced robust films that had moderate impact on the ionic conductivity but was capable of dramatically reducing the parasitic mass. Despite minimal conductivity losses, films were produced 10-15 times thinner than comparable bulk powder electrolytes thus leading to overall lower film resistance. Conductivity is maintained above 0.2mS/cm for composite electrolytes. Through the analysis of materials based on their physical properties, such as density, practical cells can be designed. Based on this, low density sulfide-solid-state electrolytes are a promising candidate for achieving the energy and safety metrics for electric aviation, however, further optimization of cathode microstructure and composite processing will be required to achieve the high power metrics and will be the focus of further studies. Additionally, fabrication challenges arise when utilizing metallic lithium foil, due to its soft nature, as overflow and mechanical short circuit can occur on assembly which remains a challenge to overcome before metallic lithium anodes can be fully realized.

batteries↗
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) Beyond Li-Ion: Technology to Enable Sustainable Electric Aviation

All-electric vertical take-off and landing vehicles (eVTOL) for urban air mobility (UAM) concepts face numerous challenging technical barriers before their introduction into the consumer marketplace. The primary barrier to overcome is developing an energy storage system capable of meeting the rigorous aerospace safety and performance criteria. The performance metrics for eVTOL vehicles are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This presentation will demonstrate a feasible path for solid-state cells that possess a specific energy of greater than 400 Wh/kg to enable electric aircraft.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRSDate not supplied

Fabrication of Solid-State Li-S Battery Components for Electric Aviation

The development of high-energy, high-safety, and high-power batteries beyond electric automobile requirements is vital for future electric aviation applications. The transition to non-volatile solid-state electrolytes (SSE) promises many advantages over traditional flammable liquid electrolytes, and may also be an enabling technology for next generation chemistries. However, significant manufacturing challenges must be overcome before the adoption of such technology. Electrolytes developed in this study were produced as sulfide-polymer composites with densified thicknesses between 20-30 microns using several processing techniques [1]. Ionic conductivity and lithium metal compatibility for the composites were compared and shown to retain reasonable ionic conductivity with improved flexibility and scalability which identifies a critical path for the production of practical solid-state batteries. Films were produced 10-15 times thinner than comparable bulk cold pressed powder electrolytes and achieved thicknesses comparable to commercial polyolefin separators (25 micron) used in commercial liquid containing lithium-ion cells. Composite conductivities were maintained above 0.2mS/cm, which holds promise for future electric aviation applications. Processing techniques are investigated to further improve electrochemical performance.

battery↗
NASA NTRSDate not supplied

Next Generation Batteries for Electric Aviation and Space

Energy storage plays a critical part in the success of future NASA missions that desire batteries with higher energy density, higher power, and most critically improved safety. These performance requirements stretch beyond that of electric automobile markets and are required for enabling widespread adoption of electric aviation. One approach to improve the safety and energy is the transition to non-volatile solid-state electrolytes (SSE) which promise many advantages over traditional flammable liquid electrolytes and may also be an enabling technology for next generation chemistries such as lithium-sulfur (Li-S). However, significant manufacturing challenges must be overcome before the adoption of such technology. This study will discuss the development of solid electrolytes specifically designed to meet future NASA electric aviation targets with densified thicknesses between 20-30 microns derived using solvent processing techniques. Films were produced 10-15 times thinner than comparable bulk cold pressed powder electrolytes and achieved thicknesses comparable to commercial polyolefin separators (25 micron) used in commercial liquid containing lithium-ion cells. Furthermore, design and development of novel cathode composites through integration of experiment and a particle dynamics model will be discussed. Beyond aeronautics, unique challenges and requirements exist for energy storage for space applications, which can cover extreme temperatures and material scarcity for in-situ derived materials. Additionally, this talk will briefly cover the need and development of lunar and Martian derived electrode materials for in-situ manufacturing of energy storage devices.

Batteries↗
NASA NTRSDate not supplied

Fabricating Solid-State Batteries for Electric Aviation

All-solid-state lithium batteries are widely reputed as the next major step in energy storage technology on account their drastically improved safety over wet cells, as solid electrolytes lack the volatile compounds in wet electrolytes that make them combustible. This enhanced safety enables a far wider range of products and vehicles to go fully electric and aligns with future NASA missions that require high performing, reliable, and safe batteries. However, they currently face issues with implementation in consumer products due to the often-poor mechanical properties of the solid electrolyte and relative difficulty to manufacture. Typical solid-state electrolyte challenges were bypassed by incorporating a range of polymeric binders into a solid electrolyte suspension and cast onto a composite carbon-sulfide cathode to create a single bilayer film. The resulting films display superior flexibility and durability compared to solid-electrolyte films typically discussed in literature without compromising the thinness of the films. The bilayer film was then punched into 12.7 cm diameter discs and 4 cm by 5 cm sheets, pressed, and assembled into coin cells and pouch cells respectively.

Batteries↗
NASA NTRSDate not supplied

ICME for NASA Aerospace Applications: Batteries for Electric Aviation

NASA’s approach to computational materials modeling is detailed in the NASA Vision 2040 Roadmap for Multiscale Modeling and Simulation of Materials and Systems. This report is in the spirit of national initiatives such as the Material Genome Initiative (MGI), Integrated Computational Materials Engineering (ICME), and others. We utilize a combination of fundamental modeling, computational high-throughput screening, and data science methods, e.g., machine learning, are used to find innovative solutions to NASA or national technology challenges. Applications of interest are wide ranging from advanced alloys to batteries to coatings, among others. In this talk, we present three examples for recent work related to NASA applications. First, doping advanced sulfur battery cathodes with selenium boosts electrical conductivity important for electric aircraft applications. First principles calculations will be discussed that result in compositional design maps for these materials. Second, development of icephobic coatings is important to mitigate safety hazards associated with icing for aircraft. Molecular dynamics simulations are reported for ice-surface interfaces to understand adhesion mechanisms and help screen optimal ice-phobic coatings. Third, shape memory alloys have numerous applications as actuators, superelastic materials, etc. for aerospace. We report machine learning models that predict martensitic transition temperatures across a broad swath of compositional space.

John Lawson↗
NASA NTRSDate not supplied

Decarbonizing Aviation with Electric Propulsion

NASA’s role in decarbonizing aviation includes the development of flight-weight, flight-ready, safe, and certifiable technologies for regional and single-aisle transport vehicles.

Rodger Dyson↗
NASA NTRSDate not supplied

Design Considerations for Practical Li-S Battery Components for Electric Aviaiton

The development of high-energy, high-safety, and high-power batteries beyond electric automobile requirements is vital for future electric aviation applications. The transition to non-volatile solid-state electrolytes (SSE) promises many advantages over traditional flammable liquid electrolytes, and may also be an enabling technology for next generation chemistries. However, significant manufacturing challenges must be overcome before the adoption of such technology. Electrolytes developed in this study were produced as sulfide-polymer composites with densified thicknesses between 20-30 microns using a tape-casting technique and elastomer binder [1]. The composites were determined to retain reasonable ionic conductivity with improved flexibility and scalability critical for practical manufacturing of such cells. Films were produced 10-15 times thinner than comparable bulk powder electrolytes and within the range of commercial polyolefin separators (25 micron) used in commercial liquid containing lithium-ion cells. Composite conductivities were maintained above 0.2mS/cm, which holds promise for future electric aviation applications. Processing techniques are investigated to further improve electrochemical performance.

battery↗
NASA NTRS2013

The NASA Environmentally Responsible Aviation Project/General Electric Open Rotor Test Campaign

The Open Rotor is a modern version of the UnDucted Fan (UDF) that was flight tested in the late 1980ʼs through a partnership between NASA and General Electric (GE). Tests were conducted in the 9ʼx15ʼ Low Speed Wind Tunnel and the 8ʼx6ʼ Supersonic Wind Tunnel starting in late 2009 and completed in early 2012. Aerodynamic and acoustic data were obtained for takeoff, approach and cruise simulations. GE was the primary partner, but other organizations were involved such as Boeing and Airbus who provided additional hardware for fuselage simulations. This test campaign provided the acoustic and performance characteristics for modern open rotor blades designs." NASA and GE conducted joint systems analysis to evaluate how well new blade designs would perform on a B737 class aircraft, and compared the results to an advanced higher bypass ratio turbofan." Acoustic shielding experiments were performed at NASA GRC and Boeing LSAF facilities to provide data for noise estimates of unconventional aircraft configurations with Open Rotor propulsion systems." The work was sponsored by NASAʼs aeronautics programs, including the Subsonic Fixed Wing (SFW) and the Environmentally Responsible Aviation (ERA) projects."

Van Zante, Dale↗
NASA NTRS2008

NASA / GE Aviation Collaborative Partnership Research in Ultra High Bypass Cycle Propulsion Concepts

Current collaborative research with General Electric Aviation on Open Rotor propulsion as part of the Subsonic Fixed Wing Project Ultra High Bypass Engine Partnership Element is discussed. The Subsonic Fixed Wing Project goals are reviewed, as well as their relative technology level compared to previous NASA noise program goals. The current Open Rotor propulsion research activity at NASA and GE are discussed including the contributions each entity bring toward the research project, and technical plans and objectives. GE Open Rotor propulsion technology and business plans currently and toward the future are also discussed, including the role the NASA SFW UHB partnership plays toward achieving those goals.

Hughes, Christopher E.↗
NASA NTRSDate not supplied

From the Knowledge-based Digital Platform (KbDP) Concept for Advanced Air Mobility Research to a Preliminary Prototype

Advanced Air Mobility (AAM) encompasses a range of innovative operational and technological changes to aviation (electric aircraft, increasingly automated aircraft, increasingly automated airspace operations, etc.) that are transforming aviation’s role in everyday movement of people and goods. There are multiple associated concepts and use cases for AAM, all interrelated, including small Unmanned Aircraft System (UAS) Traffic Management (UTM), Upper-Class E Traffic Management (ETM), Extensible Traffic Management (xTM), Regional Air Mobility (RAM), and Urban Air Mobility (UAM). These AAM operations must integrate with traditional Air Traffic Management (ATM) operations, as well as non-aviation modes of transportation and logistics. National Aeronautics and Space Administration (NASA) is spearheading an innovative digital engineering approach to integrate, communicate, and facilitate the research of multi-modal transportation systems. The Knowledge-based Digital Platform (KbDP) is a concept being developed that ties the workflows of Project Managers (PM), Principal Investigators (PI), and System Engineers together across organizational boundaries. It does so through the management of an information database defined by mathematical, data science, and system engineering principles. Machine Learning (ML) algorithms play a key role in this concept by extracting meaningful knowledge from the information database, which the human user leverages to greatly improve the efficiency and effectiveness of their research. Expected benefits of this concept include improved technology transfers from research to production, improved research portfolio investments, and research outcomes that are more integrated with all aspects of the multi-modal transportation problem. The preliminary KbDP prototype has been realized using UAM as a pathfinder use case and developed by a team of system engineer, software developer, data scientist, and interns.

Systems Engineering↗