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The development of the nickel hydrogen battery system was primarily for replacement of the nickel cadmium battery and for space power systems. A chronological review of the major events and milestones leading up to the current system status is summarized.
Electron microscopy was employed to study the process of recrystallization in two oxide dispersion strengthened (ODS) mechanically alloyed nickel-base alloys, MA 754 and MA 6000E. MA 754 contained both fine, uniformly dispersed particles and coarser oxides aligned along the working direction. Hot rolled MA 754 had a grain size of 0.5 microns and high dislocation densities. After partial primary recrystallization, the fine grains transformed to large elongated grains via secondary (or abnormal) grain growth. Extruded and rolled MA 6000E contained equiaxed grains of 0.2 micron diameter. Primary recrystallization occurring during working eliminated virtually all dislocations. Conversion from fine to coarse grains was triggered by gamma prime dissolution; this was also a process of secondary or abnormal grain growth. Comparisons were made to conventional and oxide dispersion strengthened nickel-base alloys.
The temperature dependence of the electrical resistivity, the thermal conductivity, and the thermal emf of cobalt and nickel borides were studied. In the case of the nickel borides the magnetic susceptibility and the Hall coefficient were determined at room temperature. The results are discussed with allowance for the current carrier concentration, the effect of various mechanisms of current-carrier scattering and the location of the Fermi level in relation to the 3d band.
Silicon nitride and nickel pastes are investigated in conjunction with a brush copper plating process for the purpose of identifying one or more fabrication sequences which yield at least 10 percent efficient N(+)/P(+) flat plate solar cells. The adhesion of all nickel pastes is reduced significantly when subjected to acidic and alkaline brush copper plating solutions as a result of a combination of thermally induced stress and chemical attack of the frit, which occurs at the interface with the silicon solar cell. The AgF is penetrating the 800 a of Si3N4 and ohmic contact is occurring at all fire-in tempertures. During the brush plating process, fingers and buss bars tend to spread.
An alternate nickel-cadmium cell activation scheme was developed which significantly reduces battery dissipation while maintaining the cell active material in the proper electrochemical state. The new procedure of charging at C/20 for 8 hours, C/10 for 6 hours and followed by C/5 to a voltage limit of 1.430 volt/cell significantly reduces the heat dissipation and charge period when compared to the standard activation practice of charging at C/20 for 48 hours. In addition, subsequent discharge voltage profiles using the new scheme are higher when compared to the standard practice. The effects of extended open-circuit periods on nickel-cadmium cell results in a capacity loss of approximately 0.7 percent and 1.4 percent per day at 23 and 35 degrees Celsius, respectively.
The nucleation and growth of metallic clusters on a substantially amorphous substrate are discussed with emphasis on the geometrical and electronic structure of the clusters. Several clusters of different symmetry containing five to nine nickel atoms were studied. It was found that the energy range of primary d-like states is not significantly different from the width of the d-band states in nickel metal, as long as the interatomic distance is comparable to that in the bulk metal. The approach of one or more molecules to the cluster is examined using at the hydrogenation of acetylene and the dehydrogenation of ethylene as examples.
Printed nickel overplated with copper and applied on top of a predeposited silicon nitride antireflective coating system for metallizing solar cells was analyzed. The ESL D and E paste formulations, and the new formulations F, G, H, and D-1 were evaluated. The nickel thick films were tested after firing for stability in the cleaning and plating solutions used in the Vanguard-Pacific brush plating process. It was found that the films are very sensitive to the leaning and alkaline copper solutions. Less sensitivity was displayed to the neutral copper solution. Microscopic and SEM observations show segregation of frit at the silicon nitride thick film interface with loose frit residues after lifting off plated grid lines.
The effect of cobalt on the basic mechanical properties and microstructure of wrought nickel-base superalloys has been investigated experimentally by systematically replacing cobalt by nickel in Udimet 700 (17 wt% Co) commonly used in gas turbine (jet engine) applications. It is shown that the room temperature tensile yield strength and tensile strength only slightly decrease in fine-grained (disk) alloys and are basically unaffected in coarse-grained (blading) alloys as cobalt is removed. Creep and stress rupture resistances at 760 C are found to be unaffected by cobalt level in the blading alloys and decrease sharply only when the cobalt level is reduced below 8 vol% in the disk alloys. The effect of cobalt is explained in terms of gamma prime strengthening kinetics.
Nickel was substituted for Co to produce 0, 5, and the standard 10% versions of MAR-M247, a cast nickel-base superalloy. The microstructures of the alloys were examined in as-cast, heat treated, aged, and stress-rupture tested conditions using a variety of metallographic techniques and differential thermal analysis. As cobalt concentration was reduced from 10 to 0 wt %, the gamma-prime weight fraction decreased from 59 to 41%; W and Ti concentrations in the gamma-prime phase increased from 5 to 8 and 2 to 3 at.%, respectively; the mean gamma-prime particle size increased from 0.6 to 0.8 micron; Cr and Al concentrations in the gamma matrix decreased from 17 to 13 and 15 to 12 at.%, respectively; and the weight fraction of carbides increased by approximately 1%.
Foam insulation nickel-plated with one less step. Changing tie-in layer from plasma-sprayed nickel to plasma-sprayed copper eliminates intermediate copper electroplating step previously required.
A loaded spherical aluminum oxider rider was made to slide, while in various solutions, on a flat iron or nickel surface reciprocate a distance of 1 cm. Time of experiments was 1 hr during which the rider passed over the rider passed over the center section of the track 540 times. Coefficients of friction were measured throughout the experiments. Wear was measured by scanning the track with a profilometer. Analysis of some of the wear tracks included use of the SEM (scanning electron microscrope) and XPS (X-ray photoelectron spectroscopy). Investigated were the effect of various concentractions of NaOH and of water. On iron, increasing NaOH concentration above 0.01 N caused the friction and wear to decrease. This decrease is accompanied by a decrease in surface concentration of ferric oxide (Fe2O3) while more complex iron-oxygen compounds, not clearly identified, also form. At low concentrations of NaOH, such as 0.01 N, where the friction is high, the wear track is badely torn up and the surface is broken. At high concentration, such as 10 N, where the friction is low, the wear track is smooth. The general conclusion is that NaOH forms a protective, low friction film on iron which is destroyed by wear at low concentrations but remains intact at high concentrations of NaOH. Nickel behaves differently than iron in that only a little NaOH gives a low coefficient of friction and a surface which, although roughened in the wear track, remains intact.
An evaluation of the current nickel hydrogen cell design is presented. The IPV, or the Individual Pressure Vessel, is the state of the art right now. The present design, 3 1/2 inch cell, has a current limit of 50 ampere-hours. The nickel hydrogen cell design is the state of the art. Its size is 3 1/2 inches which limits it to 50 hours. The probable limits of that are probably 160 amphere IPV cell remaining in the passive cooling mode. The IPV stacks is a parallel connection of electrodes. Positive electrodes are connected with leads to the top portion of the stack and negative electrodes are connected with leads and pulled down to the bottom. So it is a combination connection of paralleling series electrostacking--parallel inside each individual stack, and series connected from one stack to the next. It offers, in the analysis, improvements in packaging, cost, energy density, and specific energy.
Light weight energy storage systems for future space missions are investigated. One of the systems being studied is the nickel hydrogen battery. This battery is designed to achieve longer life, improve performance, and higher energy densities for space applications. The nickel hydrogen component development is discussed. Test data from polarization measurements of the hydrogen electrode component is presented.
A study has been carried out to assess the role of cobalt in Udimet 700, a representative nickel-base superalloy containing 17 percent or more cobalt. The study spans the spectrum of microstructural, microchemical, and mechanical behavior aspects which together form a basis for superalloy performance in jet engines. The results suggest that cobalt affects the solubility of elements in the gamma matrix, which leads to enhanced gamma-prime volume fraction and to the stabilization of MC-type carbides and sigma phase. However, these microstructural and microchemical changes are too slight to significantly affect the strength and ductile properties. Depending on the heat treatment, the creep and stress rupture resistance can be cobalt-sensitive. In the coarse-grained, fully solutioned and aged condition, all of the alloy's 17 percent Co can be replaced by nickel without decreasing the creep and stress rupture resistance. These findings are discussed with reference to existing theories and experimental data obtained by other workers.
A loaded spherical aluminum oxider rider was made to slide, while in various solutions, on a flat iron or nickel surface reciprocate a distance of 1 cm. Time of experiments was 1 hr during which the rider passed over the center section of the track 540 times. Coeficients of friction were measured throughout the experiments. Wear was measured by scanning the track with a profilometer. Analysis of some of the wear tracks included use of the SEM (scanning electron microscope) and XPS (X-ray photoelectron spectroscopy). Investigated were the effect of various concentrations of NaOH and of water. On iron, increasing NaOH concentration above 0.01 N caused the friction and wear to decrease. This decrease is accompanied by a decrease in surface concentration of ferric oxide (Fe2O3) while more complex iron-oxygen compounds, not clearly identified, also form. At low concentrations of NaOH, such as 0.01 N, where the friction is high, the wear track is badly torn up and the surface is broken. At high concentration, such as 10 N, where the friction is low, the wear track is smooth. The general conclusion is that NaOH forms a protective, low friction film on iron which is destroyed by wear at low concentrations but remains intact at high conentrations of NaOH. Nickel behaves differently than iron in that only a little NaOH gives a low coefficient of friction and a surface which, although roughened in the wear track, remains intact. Previously announced in STAR as N83-10171
The thermoelectric properties alloys of the nickel-base, iron-base, and cobalt-base groups containing from 1% to 25% 106 chromium were compared and correlated with the following material characteristics: atomic percent of the principle alloy constituent; ratio of concentration of two constituents; alloy physical property (electrical resistivity); alloy phase structure (percent precipitate or percent hardener content); alloy electronic structure (electron concentration). For solid-solution-type alloys the most consistent correlation was obtained with electron concentration, for precipitation-hardenable alloys of the nickel-base superalloy group, the thermoelectric potential correlated with hardener content in the alloy structure. For solid-solution-type alloys, no problems were found with thermoelectric stability to 1000; for precipitation-hardenable alloys, thermoelectric stability was dependent on phase stability. The effects of the compositional range of alloy constituents on temperature measurement uncertainty are discussed.
Results of electrical space qualification tests of nickel-hydrogen battery type HR 23S are presented. The results obtained for the nickel-cadmium battery type VO 23S are similar except that the voltage level and the charge conservation characteristics vary significantly. The electrical and thermal characteristics permit predictions of the following optimal applications: charge coefficient in the order of 1.3 to 1.4 at 20C; charge current density higher than C/10 at 20C; discharge current density from C/10 to C/3 at 20C; maximum discharge temperature: OC; storage temperature: -20C.
Long-term trends in the evolution of space power technology point toward increased payload power demand which in turn translates into both higher battery system charge storage capability and higher operating voltages. State of the art nickel-hydrogen cells of the 50 to 60 Wh size, packaged in individual pressure vessels, are capable of meeting the required cycle life for a wide range of anticipated operating conditions; however, they provided several drawbacks to battery system integrated efforts. Because of size, high voltage/high power systems require integrating hundreds of cells into the operating system. Packaging related weight and volume inefficiencies degrade the energy density and specific energy of individual cells currently at 30 Wh/cudm and 40 Wh/kg respectively. In addition, the increased parts count and associated handling significantly affect the overall battery related costs. Spacecraft battery systems designers within industry and Government realize that to reduce weight, volume, and cost requires increases in the capacity of nickel-hydrogen cells.