Solid state ampere hour integrator
Current to frequency converter solid state ampere hour integrator for evaluation of space satellite batteries
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Current to frequency converter solid state ampere hour integrator for evaluation of space satellite batteries
Component reliability analysis for 250 volt-ampere static inverter
One ampere hour heat sterilizable sealed silver zinc cell - component design and environmental testing
Acceptance testing of four ampere hour flooded sealed nickel-cadmium secondary spacecraft cells
Acceptance tests of 3.9 ampere-hr sealed nickel cadmium secondary spacecraft cells
Monge-Ampere partial differential equation for two dimensional steady MHD flows
Euler-Poisson equation extension to one dimensional MHD flow using Monge-Ampere equation
Environmental and performance tests of 6.0 ampere- hour sealed nickel cadmium secondary spacecraft batteries
Acceptance testing of 5.0 ampere-hour silver zinc secondary spacecraft cells
Acceptance tests of 5.0 ampere-hour silver-zinc cells for spacecraft power supplies
Acceptance tests of 20 ampere-hour sealed nickel-cadmium secondary spacecraft cells
Transient characteristics of voltage regulator and parasitic speed controller on 14.3-kilovolt- ampere, 1200-Hertz modified Lundell alternator
Steady-state characteristics of voltage regulator and parasitic speed controller on 14.3-kilovolt-ampere, 1200-Hz modified Lundell alternator
Acceptance tests of 100 ampere-hour nickel-cadmium cells for inclusion in life cycle program of secondary spacecraft cells
An acceptance test program was conducted on 24 cells to insure that all cells put into the life cycle program were of high quality by the removal of cells found to have electrolyte leakage, internal shorts, low capacity, or inability of any cell to recover its open circuit voltage above 1.150 volts after the cell short test. The cells were rated at 12.0 ampere-hours and equipped with auxiliary electrodes. Test results were: (1) The capacity of the 24 cells ranged from 14.6 to 16.8 ah. All the cells exceeded the rated capacity on all three capacity checks. (2) One cell failed to recover to 1.150 volts after the cell short test. (3) During the overcharge tests, all cells but one failed the test at the c/10 rate after the first minute. (4) A special resistance test was conducted on the auxiliary electrodes of these cells to establish the resistance value necessary which would provide maximum signal power across the auxiliary electrode. The resistance value established was 10 ohms. (5) No electrolyte leakage was observed.
Tests were conducted on a group of 29 cells for the purpose of removing from the life cycle program all cells found to have electrolyte leakage, internal shorts, low capacity, or inability to recover open circuit voltage above 1.150 volts after the cell short test. The test findings include the following: (1) All the cells exceeded the rated capacity of 103.5 to 119.0 ampere-hours on all three capacity checks. (2) All cells recovered above the 1.150 volt requirement after the cell short test. (3) The cells cannot be overcharged at the c/10 rate without exceeding 1.500 volts after approximately 12 to 13 hours of charge. (4) The resistance value necessary to provide maximum signal power across the auxiliary electrode was found to be 10 ohms. (5) One cell revealed a definite leak at the negative terminal.
A group of 29 cells with capacities ranging from 21.7 to 28.8 ampere-hours were tested. A summary of the results indicates: (1) All cells exceeded the rated capacity on all three capacity checks. (2) Five cells failed to recover to 1.150 volts. (3) During the overcharge tests, 15 of the 29 cells had to be removed from charge before completion of the respective tests due to high pressure.
Nickel cadmium battery cells with 100 ampere hour capacity were developed. The design features, notably extension of the current collector tab to the full width of the battery plate, and the location of the cell terminals on the opposite ends, resulted in a reduction of internal impedance, and improved electrical performance with expected improvement in thermal performance. Tables of data and performance curves are included to support the theoretical considerations.