Search NASA⌕ Search

SEARCH · Search NASA

Results for “Ni-Cd”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5

Management and Performance of APPLE Battery in High Temperature Environment

India's first experimental communication satellite, APPLE, carried a 12 AH Ni-Cd battery for supplying power during eclipse. Failure to deploy one of the two solar panels resulted in the battery operating in a high temperature environment, around 40 C. This also resulted in the battery being used in diurnal cycles rather than just half yearly eclipse seasons. The management and performance of the battery during its life of two years are described. An attempt to identify the probable degradation mechanisms is also made.

Suresh, M. S.↗

Special Test Methods for Batteries

Various methods are described for measuring heat generation in primary and secondary batteries as well as the specific heat of batteries and cell thermal conductance. Problems associated with determining heat generation in large batteries are examined. Special attention is given to monitoring temperature gradients in nickel cadmium cells, the use of auxiliary electrodes for conducting tests on battery charge control, evaluating the linear sweep of current from charge to discharge, and determining zero current voltage. The fast transient behavior of batteries in the microsecond range, and the electrical conductance of nickel sinters in the thickness direction are also considered. Mechanical problems experienced in the vibration of Ni-Cd batteries and tests to simulate cyclic fatigue of the steel table connecting the plates to the comb are considered. Methods of defining the distribution of forces when cells are compressed during battery packaging are also explored.

Gross, S.↗

Degradation in nickel-cadmium cells studied by impedance measurements

The impedance characteristics of various Ni-Cd cells were measured at different times during accelerated charge/discharge trials to identify characteristics indicative of cell lifetime and cycle history. The tests were performed as part of an attempt to develop nondestructive testing techniques to detect flaws in batteries installed on low-earth orbit satellites. Trials consisted of 60 min charging and 40 min discharging, covering 20, 30, and 40 C temperatures, 20, 35, and 50 percent depth of discharge, and the average cycle life. No correlations were derived between impedance characteristics and cycle life. Other possible techniques for evaluating predictors of battery performance are discussed.

Haak, R.↗

Nickel-cadmium Battery Cell Reversal from Resistive Network Effects

During the individual cell short-down procedures often used for storing or reconditioning nickel-cadmium (Ni-Cd) batteries, it is possible for significant reversal of the lowest capacity cells to occur. The reversal is caused by the finite resistance of the common current-carrying leads in the resistive network that is generally used during short-down. A model is developed to evaluate the extent of such a reversal in any specific battery, and the model is verified by means of data from the short-down of a f-cell, 3.5-Ah battery. Computer simulations of short-down on a variety of battery configurations indicate the desirability of controlling capacity imbalances arising from cell configuration and battery management, limiting variability in the short-down resistors, minimizing lead resistances, and optimizing lead configurations.

Zimmerman, A. H.↗

Grace DAKASEP alkaline battery separator

The Grace DAKASEP separator was originally developed as a wicking layer for nickel-zinc alkaline batteries. The DAKASEP is a filled non-woven separator which is flexible and heat sealable. Through modification of formulation and processing variables, products with a variety of properties can be produced. Variations of DAKASEP were tested in Ni-H2, Ni-Zn, Ni-Cd, and primary alkaline batteries with good results. The properties of DAKASEP which are optimized for Hg-Zn primary batteries are shown in tabular form. This separator has high tensile strength, 12 micron average pore size, relatively low porosity at 46-48 percent, and consequently moderately high resistivity. Versions were produced with greater than 70 percent porosity and resistivities in 33 wt percent KOH as low as 3 ohm cm. Performance data for Hg-Zn E-1 size cells containing DAKASEP with the properties shown in tabular form, are more reproducible than data obtained with a competitive polypropylene non-woven separator. In addition, utilization of active material is in general considerably improved.

Giovannoni, R. T.↗

The ingestible thermal monitoring system

A thermal monitoring system for measuring body core temperatures was developed that contains an ingestible pill which is both commandable and rechargeable, and which uses magnetic induction for command and telemetry as well as for recharging. The pill electronics consist of a battery power source, a crystal-controlled oscillator that drives a small air coil, and a command detection circuit. The resulting 262-kHz magnetilc field can be easily detected from a distance of 1 m. The pill oscillator functions at voltages less than 1 V, supplied by a single Ni-Cd battery, which must be recharged after 72 h of continuous transmission. The pill can be recalibrated periodically to compensate for long-term drift.

Cutchis, Protagoras N.↗

Nickel cadmium battery performance simulation - A means toward optimum design in satellite applications

It is noted that electrochemically based cell models can advance state-of-the-art battery prediction by allowing variations in the parameters that constitute wear-out and predict end-of-life performance. This modeling method is used as the foundation for the simulation of Ni-Cd battery performance. This simulation tool consists of a comprehensive computer model to be developed which would predict the voltage behavior of a battery under mission conditions.

Clark, K.↗

Energy storage considerations for a robotic Mars surface sampler

The characteristics of various energy storage systems (including Ni-Cd, Ni-H2, Ag-Zn, Li-XS, Na-S, PbSO4, and regenerative fuel cell systems) considered for a robotic Mars surface sampler are reviewed. It is concluded that the bipolar nickel-hydrogen battery and the sodium-sulfur battery are both viable candidates as storage systems for the rover's Radioisotope Thermoelectric Generator. For a photovoltaic storage system, the regenerative fuel cell and the bipolar nickel-hydrogen battery are the primary candidates.

O'Donnell, P. M.↗

The importance of batteries in unmanned missions

The planetary program has historically used batteries to supply peak power needs for mission specific applications. Any time that additional power has been required in order to meet peak power demands or those applications where only limited amounts of power were required, batteries have always been used. Up until the mid to late 70s they have performed their task admirably. Recently, a growing problem of developing reliable Ni-Cd batteries for long mission and high cycle life applications has been identified. This problem and the role rechargeable batteries will play for future planetary and earth-observing spacecraft, are discussed.

Klein, John W.↗

A mathematical model of a sealed nickel-cadmium battery

A mathematical model for the charge and discharge of a sealed nickel-cadmium (Ni-Cd) battery is presented. The model is used to study the effect of transport properties of the electrolyte and kinetic parameters of the electrode reactions on the cell performance during the charge and discharge period. The model can also be used to demonstrate the changes of cell performance during cycling. Some comparisons between model predictions and experimental results indicate that the model predictions appear to fit the experimental data well. Sensitivity analyses illustrate that the sealed nickel-cadmium battery operates under activation control. It is also shown theoretically that oxygen generated on the positive electrode during charge is reduced electrochemically on the negative electrode.

Fan, Deyuan↗

Mathematical modeling of a nickel-cadmium battery

Extensions are presented for a mathematical model of an Ni-CD cell (Fan and White, 1991). These extensions consist of intercalation thermodynamics for the nickel electrode and oxygen generation and reduction reactions during charge and overcharge. The simulated results indicate that intercalation may be important in the nickel electrode and that including the oxygen reactions provides a means of predicting the efficiency of the cell on charge and discharge.

Fan, Deyuan↗

Report of investigations into charge cadmium reactivity: Nickel-cadmium cell ESD 91-86

In Aug. 1990, a presentation was given at the 25th Ann. IECEC meeting on the results of Destructive Physical Analysis (DPA) on two successive sets of Ni-Cd cells. The cells were of two different separator types, Pellon 2505 and 2536. One cell of each separator type was analyzed on two occasions; the first pair were analyzed to establish baseline data on essentially new cells; the second pair were analyzed after the cells had been on charge-discharge cycling for a year in connection with a satellite simulation study. The gas composition found in the cells, the absence of charged cadmium in the analytical data, and the appearance of dried out portions on the Cd plates in the one year cell S/N 7 which used Pellon 2505 as its separator material, were questions which arose. These concerns are answered and the observational results are clarified.

Lewis, Harlan L.↗

TOPEX electrical power system

The TOPEX mission requirements which impact the power requirements and analyses are presented. A description of the electrical power system (EPS), including energy management and battery charging methods that were conceived and developed to meet the identified satellite requirements, is included. Analysis of the TOPEX EPS confirms that all of its electrical performance and reliability requirements have been met. The TOPEX EPS employs the flight-proven modular power system (MPS) which is part of the Multimission Modular Spacecraft and provides high reliability, abbreviated development effort and schedule, and low cost. An energy balance equation, unique to TOPEX, has been derived to confirm that the batteries will be completely recharged following each eclipse, under worst-case conditions. TOPEX uses three NASA Standard 50AH Ni-Cd batteries, each with 22 cells in series. The MPS contains battery charge control and protection based on measurements of battery currents, voltages, temperatures, and computed depth-of-discharge. In case of impending battery depletion, the MPS automatically implements load shedding.

Chetty, P. R. K.↗

Modelling of nickel-cadmium batteries using porous electrode theory

A porous electrode modeling technique is discussed which is considered a viable means for quantitatively predicting Ni-Cd cell performance. The authors describe the integration of the cell model into a battery model useful in the design and operation of aerospace applications. Test data from a sealed boilerplate cell are presented for constant current charge and discharge conditions. Performance predictions for similar cases have been performed, and a comparison to the boilerplate data is made. Areas for further development are also noted.

Timmerman, Paul J.↗

Preliminary results: Root cause investigation of orbital anomalies and failures in NASA standard 50 ampere-hour nickel-cadmium batteries

Two lots of NASA standard 50 A.H. Ni-Cd battery cells, manufactured by Gates Aerospace Batteries and built into batteries by McDonnell Douglas, have experienced significant performance problems. The two lots were used on the Compton Gamma Ray Observatory and the Upper Atmosphere Research Satellite. Both of these satellites are Low Earth Orbital (LEO) satellites containing batteries on a parallel bus charged to NASA standard V/T curves using a NASA standard power regulator. The following preliminary conclusions were reached: (1) several plate and cell parameters have migrated within their spec limits over the years (in some cases, from one extreme to the other); (2) several parametric relationships, not generally monitored and therefore not under specification control, have also migrated over the years; (3) many of these changes appear to have taken place as a natural consequence of changes in GE/GAB materials and processes; (4) several of these factors may be 'conspiring' to aggravate known cell failure mechanisms (factors such as heavier plate, less teflon and/or less-uniform teflon, and less electrolyte) but all are still in spec (where specs exist); (5) the weight of the evidence collected to characterize the anomalies and to characterize the negative electrode itself, strongly suggests that alterations to the structure, composition, uniformity, and efficiency of the negative electrode are at the heart of the battery performance problems currently being experienced; and (6) further investigation at all levels (plate, cell, battery, and system) continues to be warranted.

Toft, Mark R.↗

Cycle life status of SAFT VOS nickel-cadmium cells

The SAFT prismatic VOS Ni-Cd cells have been flown in geosynchronous orbit since 1977 and in low earth orbit since 1983. Parallel cycling tests are performed by several space agencies in order to determine the cycle life for a wide range of temperature and depth of discharge (DOD). In low Earth orbit (LEO), the ELAN program is conducted on 24 Ah cells by CNES and ESA at the European Battery Test Center at temperatures ranging from 0 to 27 C and DOD from 10 to 40 percent. Data are presented up to 37,000 cycles. One pack (X-80) has achieved 49,000 cycles at 10 C and 23 percent DOD. The geosynchronous orbit simulation of a high DOD test is conducted by ESA on 3 batteries at 10 C and 70, 90, and 100 percent DOD. Thirty-one eclipse seasons are completed, and no signs of degradation have been found. The Air Force test at CRANE on 24 Ah and 40 Ah cells at 20 C and 80 percent DOD has achieved 19 shadow periods. Life expectancy is discussed. The VOS cell technology could be used for the following: (1) in geosynchronous conditions--15 yrs at 10-15 C and 80 percent DOD; and (2) in low earth orbit--10 yrs at 5-15 C and 25-30 percent DOD.

Goualard, Jacques↗

Determination of thermal properties of commercial Ni-MH cells

The test objectives were to evaluate the electrical and thermal performance of commercial Ni-MH cells, evaluate the effectiveness of commercial charge control circuits, assess the abuse tolerance of these cells, and correlate performance and abuse tolerances to cell design via disassembly. Design objectives were to determine which cell designs are most suitable for scale-up and to guide the design of future shuttle and space station based battery chargers. Results, displayed in viewgraph format, include: reflex charging with ICS circuit resulted in premature charge termination; Ni-MH cells appear very tolerant to overcharge at low rates; Enstore's charger is more electrically and thermally efficient at high rates; and Ni-MH cycles much more efficiently than Ni-Cd with the delta-V/delta-t termination.

Darcy, Eric C.↗

First principles nickel-cadmium and nickel hydrogen spacecraft battery models

The principles of Nickel-Cadmium and Nickel-Hydrogen spacecraft battery models are discussed. The Ni-Cd battery model includes two phase positive electrode and its predictions are very close to actual data. But the Ni-H2 battery model predictions (without the two phase positive electrode) are unacceptable even though the model is operational. Both models run on UNIX and Macintosh computers.

Timmerman, P.↗