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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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Development of Flexible Energy Storage Device for Wearable Electronics using All-organic Composites

As the demands and applications of wearable electronics increase, the need of power supply for wearable electronics becomes the critical issue. Both batteries and capacitors can be used as power supplier. In terms of energy storage device, capacitors have many advantages over the batteries, but have a lower energy storage density. To improve the energy density, composites, in which inorganic particles are embedded in a polymer matrix, have been identified as a promising approach to create the dielectrics with a higher energy storage density. The physics behind the composite approach is that the inorganics have a higher dielectric constant and polymers can stand with a higher electric field so that the composites can exhibit a relative dielectric constant and stand with a relative electric field. Therefore, the composites can exhibit a higher energy storage density. However, the embedment of inorganic particles into polymer severely reduces the flexibility of the polymer. To develop flexible energy storage ultracapacitors as an energy storage device for wearable electronics, an all-organic composite approach, in which a dielectric polymer is mixed with polar organic molecules, is introduced. It is experimentally found that by adding a small amount of polar organic molecules into dielectric polymers, the polymers exhibits a high dielectric constant and can stand with a higher electric field. More importantly, the flexibility of the all-organic composites is better than the polymer matrix. Therefore, the all-organic composites can be a strong and promising candidate for the development of flexible energy storage devices for the wearable electronics. In this study, three different dielectric polymers and three different polar molecules were studied. All the all-organic composite systems exhibit a significant improvement on the energy storage density. These new flexible energy storage devices are being developed to be fabricated with on-demandadditive electronics manufacturing processes, so that they can be fabricated when needed in space on the International Space Station and planned lunar habitat and other future missions. These flexible energy storage devices will provide the storage in concert with other printed power generation devices to allow crew health and structural health monitoring sensor devices and systems to be self-powered, not requiring any external power or batteries.

energy storage↗

Process Development for Printing Copper Conductible Ink on Flexible Substrates Using Aerosol Jet Technology

Rise in demand for wearable consumer electronics products has given an impetus to the development of flexible electronics technology encompassing flexible substrates and compatible circuitry. Also, additive manufacturing of flexible electronics is emerging rapidly via several techniques such as Inkjet and Aerosol Jet Printing (AJP). The basic component of all flexible circuits to be printed by these technologies is conductible ink, which is generally silver ink. Few studies exist on the printing of copper conductible ink and not many copper ink formulations are available in the market as that of silver inks. This study aims to develop a process development study for deposition of copper conductible lines on flexible substrates using the aerosol jet printing technology. The process development study includes investigation of photosintering parameters for obtaining desirable electrical resistance and shear load to failure values for the printed line. Different pre-drying techniques such as oven pre-drying and platen pre-drying have been used for improving the electrical and mechanical properties of the conductive traces. Techniques such as optical microscopy and white light interferometry have been used for the characterization of print quality of the conductible lines.

printed electronics↗

Ultra-Thin, Flexible Electronics

Thinned die can be used to realize ultra-thin flexible electronics for applications such as conformal and wearable electronics. Three techniques have been developed to achieve this goal using thinned die: die flip chip bonded onto flexible substrates, die laminated onto LCP films, and die embedded in polyimide. A key to achieving each of these techniques is the thinning of die to a thickness of 50 microns or thinner. Conventional CMP processing can be used to thin to 50 microns. At 50 microns, the active die become flexible and must be handled by temporarily bonding them to a holder die, for further processing. Once bonded face down to the holder die, the active die can be further thinned by DRIE etching the exposed backside. The thinned die can then been packaged in or on the flexible substrate.

electronics packaging↗

Print-Consistency and Process-Interaction for Inkjet-Printed Copper on Flexible Substrate

Printed electronics is a fastest growing and emerging technology that have shown much potential in several industries including automotive, wearables, healthcare, and aerospace. Its applications can be found not only in flexible but also in large area electronics. The technology provides an effective and convenient method to additively deposit conductive and insulating materials on any type of substrate. Comparing with traditional manufacturing processes, which involves chemical etching, this technology also comes to be relatively environmental friendly. Despite its status, it is not without its challenges. Starting from the material being compatible in the printer equipment to the point of achieving fine resolutions, and with excellent properties are some of the challenges that printed electronics face. Among the myriad of printing technologies such as Aerosol Jet, micro-dispensing, gravure printing, screen printing, Inkjet printing, Inkjet has gained much attention due to its low-cost, low material consumption, and roll-to-roll capability for mass manufacturing. The technology has been widely used in home and office, but recently gained interest in printed electronics in a research and development setting. Conductive materials used in Inkjet printing generally comprises of metal Nanoparticles that need to be thermally sintered for it to be conductive. The preferred metal of choice has been mostly silver due to its excellent electrical properties and ease in sintering. However, silver comes to be expensive than its counterpart copper. Since copper is prone to oxidation, much focus has been given towards photonic sintering that involves sudden burst of pulsed light at certain energy to sinter the copper Nanoparticles. With this technique, only the printed material gets sintered in a matter of seconds without having a great impact on its substrate, due to which it is also preferred in low temperature applications. With all the knowledge, there is still a large gap in the process side with copper where it is important to look how the print process affects the resolution of the print along with the effect of post-print processes on electrical and mechanical properties. In this paper, a copper Inkjet ink is utilized for understanding the effect of Inkjet print parameters on the ejected droplet and its resolution. Post-print process is also quantified using a photonic sintering equipment for excellent electrical and mechanical properties. To demonstrate the complete process, commercial-off-the-shelf components will also be mounted on the additively printed pads via Inkjet. Statistically, control charting technique will be utilized to understand the capability of the Inkjet process.

printed electronics↗

AIAA Ascend 2021 Conference On Demand Manufacturing of Electronics Panel Abstract

1. Session Proposal o Session Title NASA’s In Space Manufacturing and the On Demand Manufacturing of Electronics o Session Topic Primary -- Space Logistics, Autonomy, and Robotics; Secondary – Transformative Research and Technologies o Session Format: Panel Discussion. o Requested Session Duration: 60 minutes o Short Session Description: The goal of NASA’s On Demand Manufacturing of Electronics project is to develop and demonstrate the feasibility of a low-gravity, on-demand manufacturing system for flexible hybrid electronic devices on the International Space Station. This panel will feature several key collaborators and team members from the commercial sector, academia, and internal to NASA, each of which are contributing an unique and vital role to the design and implementation of this new technology system. o Extended Session Description (Please describe in detail the activity proposed, including how you intend to use the requested session duration. This session description will be provided to the reviewers for consideration and will not be displayed in the online agenda.): The session will be moderated by Curtis Hill, the Project Lead for the On Demand Manufacturing of Electronics (ODME), and he will start by giving a brief introduction to the ODME project which is working to produce a demo system for the manufacturing of electronic devices on the International Space Station. Panelists consisting of collaborators and team members to the ODME project will then give a brief (~5 min) introduction highlighting their contributions to the project, followed by time for Q&A from the audience. The panel will consist of: 1. Kenneth Church, nScrypt. nScrypt is a leader in multi-material printing with a modular system that incorporates a direct write thick film print head, a polymer fused filament fabrication print head, a laser sintering attachment, a drill head attachment for milling, and a pick and place. The system can print a layer and scan for accuracy of prints. The combination of multiple print heads and scanning allows for the on-demand production of intricate electronic components. 2. Andy Kurk, TechShot, Inc. Techshot, Inc. has collaborated extensively with NASA on the in space manufacturing of both printed electronics and fused metal materials. They are currently working to develop and integrate a test system for printed electronics, and a flight demonstration on the International Space Station is anticipated in 2024. 3. Ed Hendricks, NextFlex. NextFlex has the goal of advancing the manufacture of flexible hybrid electronics in the U.S. They are working with ODME on the development of AstroSense, an additively manufactured, wireless, flexible, and wearable health sensor. 4. Dr. Pradeep Lall, Auburn University. Professor Lall is the MacFarlane Endowed Distinguished Professor in the Department of Mechanical Engineering with a Courtesy Joint Appointment in the Department of Electrical and Computer Engineering and a Courtesy Joint Appointment in the Department of Finance. He is collaborating with NASA’s ODME project to develop multilayer printable devices and to develop techniques to test the quality of a printed electronic device. 5. Dr. Wei Gao, California Institute of Technology. Professor Gao is an Assistant Professor of Medical Engineering. His group is developing fully printed, flexible, and wearable biosensors for crew health monitoring in collaboration with NASA’s ODME project. In addition, they are working on using sweat to power biofuel cells for wearable, self-powered electronic devices. 6. Beth Paquette, NASA Goddard. The ODME branch at NASA Goddard is spearheading a sounding rocket flight demo to prove the capability of a printed electronic device with multiple sensors. In addition, they focus on thin film and flexible energy storage evaluations. o Session Goal(s)/Outcome(s): Please list the learning objectives and/or tangible outcomes (technical paper or other publication). The goal of this session is to highlight the internal and collaborative efforts of NASA’s On Demand Manufacturing of Electronics project to develop a system for printing electronics that will be tested on the International Space Station in 2024. In addition, the session with facilitate discussion with the community on the state of the art of printable electronics, current challenges, and new avenues for collaboration.

Jennifer McInnis Jones↗

Damage Detection Sensor System for Aerospace and Multiple Applications

NASA has identified structural health monitoring and damage detection and verification as critical needs in multiple technology roadmaps. The sensor systems can be customized for detecting location, damage size, and depth, with velocity options and can be designed for particular environments for monitoring of impact or physical damage to a structure. The damage detection system has been successfully demonstrated in a harsh environment and remote integration tested over 1000 miles apart. Multiple applications includes: Spacecraft and Aircraft; Inflatable, Deployable and Expandable Structures; Space Debris Monitoring; Space Habitats; Military Shelters; Solar Arrays, Smart Garments and Wearables, Extravehicular activity (EVA) suits; Critical Hardware Enclosures; Embedded Composite Structures; and Flexible Hybrid Printed Electronics and Systems. For better implementation and infusion into more flexible architectures, important and improved designs in advancing embedded software and GUI interface, and increasing flexibility, modularity, and configurable capabilities of the system are currently being carried out.

Williams, Martha↗

Overview of MSFC Additive Electronics Capabilities

Focus: Marshall seeks to support the Agency in the development of next generation printed electronics technologies for living and working in space, with emphasis on enhanced electronics manufacturing processes and capabilities development on the ground and in-space. Near-Term: Human Habitation Elements and Life Support Systems - pursuing integrated flexible wearable air, water, vital monitoring solutions for next generation printed technologies; Complete startup printing technology demonstrations which prove basic processes and establish ISM (In-Space Manufacturing) infrastructure needed for future applications including metals based manufacturing. Medium Term: Target low-cost research and demonstration activities that support multi-material additive manufacturing, more sophisticated parts production, printed electronics and ISM; Maturation and flight demonstration of printed propulsion system components, with emphasis on infusion into small-spacecraft-based missions. Long-Term: Evolve systems capabilities to be supportive of destination (lunar or Mars) resources and requirements, increase autonomy in systems and utilize in-situ resources towards manufacturing; Support development of self-replicable systems and their infusion into future spacecraft and missions.

MacLeod, Todd C.↗

An Ultra-long Life, High-performance, Flexible Li-CO2Battery Based on Multifunctional Carbon Electrocatalysts

Integrating CO2 utilization and renewable energy delivery/storage, the rechargeable Li–CO2 battery has been considered as a promising candidate for next-generation secondary batteries. However, high-performance catalyst(s) for efficient formation and decomposition of the discharge product, Li2CO3, are an imperative part of a Li–CO2 battery. The development of flexible Li–CO2 batteries extends their applications into compliant and wearable devices/systems, but at the same time imposes a big challenge for battery fabrication and lifetime enhancement. In this study, a rechargeable quasi-solidus flexible Li–CO2 battery was designed and fabricated using highly active N,S-doped carbon nanotubes (N,S-doped CNTs) as the cathode catalyst, and a smart polymer gel as the flexible electrolyte. This newly-developed flexible Li–CO2 battery exhibited a capacity as high as 23560 mAh g−1 based on the catalyst mass and an ultra-long lifetime of up to 538 cycles with excellent mechanical flexibility. This work provides a platform for the design and development of high-performance flexible Li–CO2 batteries from low-cost, earth-abundant, carbon-based multifunctional cathode catalysts.

Superior stability↗

E-Textile Antennas for Space Environments

The ability to integrate antennas and other radio frequency (RF) devices into wearable systems is increasingly important as wireless voice, video, and data sources become ubiquitous. Consumer applications including mobile computing, communications, and entertainment, as well as military and space applications for integration of biotelemetry, detailed tracking information and status of handheld tools, devices and on-body inventories are driving forces for research into wearable antennas and other e-textile devices. Operational conditions for military and space applications of wireless systems are often such that antennas are a limiting factor in wireless performance. The changing antenna platform, i.e. the dynamic wearer, can detune and alter the radiation characteristics of e-textile antennas, making antenna element selection and design challenging. Antenna designs and systems that offer moderate bandwidth, perform well with flexure, and are electronically reconfigurable are ideally suited to wearable applications. Several antennas, shown in Figure 1, have been created using a NASA-developed process for e-textiles that show promise in being integrated into a robust wireless system for space-based applications. Preliminary characterization of the antennas with flexure indicates that antenna performance can be maintained, and that a combination of antenna design and placement are useful in creating robust designs. Additionally, through utilization of modern smart antenna techniques, even greater flexibility can be achieved since antenna performance can be adjusted in real-time to compensate for the antenna s changing environment.

Kennedy, Timothy F.↗