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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 paraffin-actuated heat switch has been developed for thermal control of the batteries used on the 2003 Mars Exploration Rovers.
Both pulsed and continuous outputs available. Switching power-supply circuit converts input power from two 9-V batteries in series to output of 5 Vdc regulated within 1.5 percent, either at continuous current of 5 mA or at current of 500 mA in 0.5-s pulses at 1-min intervals. Power supply is buck converter. Principle of operation inductive and capacitive filtering of controlled pulses of battery voltage.
High-power batteries generally consist of a series connection of many cells or cell banks. In order to maintain high performance over battery life, it is desirable to keep the state of charge of all the cell banks equal. A method provides individual charging for battery cells in a large, high-voltage battery array with a minimum number of transformers while maintaining reasonable efficiency. This is designed to augment a simple highcurrent charger that supplies the main charge energy. The innovation will form part of a larger battery charge system. It consists of a transformer array connected to the battery array through rectification and filtering circuits. The transformer array is connected to a drive circuit and a timing and control circuit that allow individual battery cells or cell banks to be charged. The timing circuit and control circuit connect to a charge controller that uses battery instrumentation to determine which battery bank to charge. It is important to note that the innovation can charge an individual cell bank at the same time that the main battery charger is charging the high-voltage battery. The fact that the battery cell banks are at a non-zero voltage, and that they are all at similar voltages, can be used to allow charging of individual cell banks. A set of transformers can be connected with secondary windings in series to make weighted sums of the voltages on the primaries.
A development program is being conducted at Advanced Thermal Batteries (ATB) to create a low discharge rate, long life, molten salt battery for a NASA Venus surface probe. Battery goals are 60 days continuous operation at +25V +0/-6 volts and -25V +6/-0 Volts under severe environments of 465°C, 92 atm pressure, and corrosive sulfur dioxide in a super critical carbon dioxide atmosphere. Conveniently, molten salt thermal battery electrochemistry starts to operate efficiently at 330°C. However, a major barrier to direct application of existing thermal battery technology is the high self-discharge rate, resulting in lifetimes in only minutes, not days. The best performance to date, which meets the required voltage regulation, has been a lithium silicon (LiSi) alloy anode discharging through all three voltage plateau versus an iron monosulfide (FeS) cathode. In order to perform reproducibly, additional engineering controls within the battery design are required to limit cell–to–cell parasitic discharge mechanisms. Results of these trials have improved the efficiency and manufacturability of the design.
The interaction, effect, and controllability of the performance parameters of the General Electric 20-ampere-hour, 24-cell nickel cadmium battery are investigated. The battery was cycled under simulated orbit conditions. The acquired data was analyzed and evaluated in terms of battery parameters and performance characteristics. Conclusions and tests results are presented along with recommendations for further study.
Topics include: Bioreactors Drive Advances in Tissue Engineering; Tooling Techniques Enhance Medical Imaging; Ventilator Technologies Sustain Critically Injured Patients; Protein Innovations Advance Drug Treatments, Skin Care; Mass Analyzers Facilitate Research on Addiction; Frameworks Coordinate Scientific Data Management; Cameras Improve Navigation for Pilots, Drivers; Integrated Design Tools Reduce Risk, Cost; Advisory Systems Save Time, Fuel for Airlines; Modeling Programs Increase Aircraft Design Safety; Fly-by-Wire Systems Enable Safer, More Efficient Flight; Modified Fittings Enhance Industrial Safety; Simulation Tools Model Icing for Aircraft Design; Information Systems Coordinate Emergency Management; Imaging Systems Provide Maps for U.S. Soldiers; High-Pressure Systems Suppress Fires in Seconds; Alloy-Enhanced Fans Maintain Fresh Air in Tunnels; Control Algorithms Charge Batteries Faster; Software Programs Derive Measurements from Photographs; Retrofits Convert Gas Vehicles into Hybrids; NASA Missions Inspire Online Video Games; Monitors Track Vital Signs for Fitness and Safety; Thermal Components Boost Performance of HVAC Systems; World Wind Tools Reveal Environmental Change; Analyzers Measure Greenhouse Gasses, Airborne Pollutants; Remediation Technologies Eliminate Contaminants; Receivers Gather Data for Climate, Weather Prediction; Coating Processes Boost Performance of Solar Cells; Analyzers Provide Water Security in Space and on Earth; Catalyst Substrates Remove Contaminants, Produce Fuel; Rocket Engine Innovations Advance Clean Energy; Technologies Render Views of Earth for Virtual Navigation; Content Platforms Meet Data Storage, Retrieval Needs; Tools Ensure Reliability of Critical Software; Electronic Handbooks Simplify Process Management; Software Innovations Speed Scientific Computing; Controller Chips Preserve Microprocessor Function; Nanotube Production Devices Expand Research Capabilities; Custom Machines Advance Composite Manufacturing; Polyimide Foams Offer Superior Insulation; Beam Steering Devices Reduce Payload Weight; Models Support Energy-Saving Microwave Technologies; Materials Advance Chemical Propulsion Technology; and High-Temperature Coatings Offer Energy Savings.
Commentary on active and passive satellite communication devices including attitude control, solar cells, batteries, etc
Signal electrode charge control of sealed Ni-Cd batteries, discussing signal voltage for overcharge control
Alkaline-type coulometer cell for primary charge control in secondary battery recharge circuits
The Department of Energy has developed a program to effect a large reduction in the price of photovoltaic modules, with significant progress already achieved toward the 1986 goal of 50 cents/watt (1975 dollars). Remaining elements of a P/V power system (structure, battery storage, regulation, control, and wiring) are also significant cost items. The costs of these remaining elements are commonly referred to as Balance-of-System (BOS) costs. The BOS costs are less well defined and documented than module costs. The Lewis Research Center (LeRC) in 1976/77 and with two village power experiments that will be installed in 1978. The costs were divided into five categories and analyzed. A regression analysis was performed to determine correlations of BOS Costs per peak watt, with power size for these photovoltaic systems. The statistical relationship may be used for flat-plate, DC systems ranging from 100 to 4,000 peak watts. A survey of suppliers was conducted for comparison with the predicted BOS cost relationship.
Missions for hybrid vehicles that promise to yield high petroleum impact were identified and a preliminary design, was developed that satisfies the mission requirements and performance specifications. Technologies that are critical to successful vehicle design, development and fabrication were determined. Trade-off studies to maximize fuel savings were used to develop initial design specifications of the near term hybrid vehicle. Various designs were "driven" through detailed computer simulations which calculate the petroleum consumption in standard driving cycles, the petroleum and electricity consumptions over the specified missions, and the vehicle's life cycle costs over a 10 year vehicle lifetime. Particular attention was given to the selection of the electric motor, heat engine, drivetrain, battery pack and control system. The preliminary design reflects a modified current compact car powered by a currently available turbocharged diesel engine and a 24 kW (peak) compound dc electric motor.
An environmental control subsystem (ECS) in the passenger compartment of electric and hybrid vehicles is studied. Various methods of obtaining the desired temperature control for the battery pack is also studied. The functional requirements of ECS equipment is defined. Following categorization by methodology, technology availability and risk, all viable ECS concepts are evaluated. Each is assessed independently for benefits versus risk, as well as for its feasibility to short, intermediate and long term product development. Selection of the preferred concept is made against these requirements, as well as the study's major goal of providing safe, highly efficient and thermally confortable ECS equipment.
Proposed instrument measures tension in tether and transmits data on tension so tension monitored or adjusted as necessary. Positioned along length of tether, which measures tension only at ends. Device includes strain gauge to sense tension. Output of strain gauge controls modulation of battery- or solar-powered radio transmitter. In another version, transmitter receives radio signal on one frequency and returns signal on another frequency with modulation signifying tension. Yet another version, data on tension carried on beam of light. Laser-diode transmitter powered by battery, radio beam, beam of light, or solar energy.
Component qualification and acceptance temperatures are derived from worst case thermal analyses and analytic uncertainty margin subject to certain specified temperature extremes. Temperature requirements are shown for equipment operation within specification and for survival and turn-on (need not operate within specification, but must not experience any degradation when returned to operational range). Temperature excursions for most equipment are seen to be 20 to 50 C above and below room temperature. Components without active electronics which are mounted outboard, such as solar arrays and antennas, are usually designed to withstand wider temperature excursions, particularly at the cold end. Batteries are tightly controlled at cold temperatures to increase life. Payload components such as extremely accurate clocks for precise navigation are controlled over a relatively narrow temperature range.
Joust 1 will carry a payload of 10 experiments. The experiments in the payload module will be mated with a service module containing accelerometers, avionics, a low gravity rate control system, and battery packs. This suborbital mission will last approximately 21 minutes, providing at least 13 minutes of microgravity time. The experiments are as follow: study into polymer membrane processes; polymer curing; plasma particle generation; automated generic bioprocessing apparatus; biomodule; thin films; materials dispersion apparatus; foam formation; electrodeposition process; and powdered materials processing.
This document presents in viewgraph format information on bipolar battery development at Johnson Controls, Incorporated. The organization structure, goals, progress to date, future plans, and battery parameters and electrical properties are given.
A device and method for harvesting, generating, storing, and delivering energy to a load, particularly for remote or inaccessible applications. The device preferably comprises one or more energy sources, at least one supercapacitor, at least one rechargeable battery, and a controller. The charging of the energy storage devices and the delivery of power to the load is preferably dynamically varied to maximize efficiency. A low power consumption charge pump circuit is preferably employed to collect power from low power energy sources while also enabling the delivery of higher voltage power to the load. The charging voltage is preferably programmable, enabling one device to be used for a wide range of specific applications.
A device and method for harvesting, generating, storing, and delivering energy to a load, particularly for remote or inaccessible applications. The device preferably comprises one or more energy sources, at least one supercapacitor, at least one rechargeable battery, and a controller. The charging of the energy storage devices and the delivery of power to the load is preferably dynamically varied to maximize efficiency. A low power consumption charge pump circuit is preferably employed to collect power from low power energy sources while also enabling the delivery of higher voltage power to the load. The charging voltage is preferably programmable, enabling one device to be used for a wide range of specific applications.