Nickel hydride batteries gained a firm foothold in the post-war consumer market. However, the technology had its limitations, and so NASA needed something more suitable for its satellites. Nickel-hydrogen batteries appeared in the early 1970’s as rechargeable energy storage systems. We provide an overview of one which proved remarkably reliable.
A Brief Overview of Nickel-Hydrogen Batteries
We are more familiar with the nickel-metal-hydride batteries that appeared in the late 1980’s a decade later. But their parent nickel-hydrogen batteries differed from them, in the sense they used the hydrogen in a gaseous form. And this stored in a pressurized cell at up to 1,200 pounds per square inch.
To put this in context, the average auto passenger tire inflates to 32 to 35 pounds per square inch. So already it becomes clear Alexandr Ilich Kloss and Boris Ioselevich Tsenter’s technology was not something you would want to put in your flashlight or smartphone.
More Detail about the Inner Workings of Nickel-Hydrogen
Nickel-hydrogen batteries are a fusion technology. That’s because they combine the nickel positive electrode of a nickel-cadmium battery, and the negative electrode, including the catalyst and gas diffusion elements, of a fuel cell according to Wikipedia.
Hydrogen contained in the pressure vessel is oxidized into water during discharge. While the nickel oxyhydroxide electrode is reduced to nickel hydroxide. The system consumes water at the hydrogen electrode, so the concentration of the potassium hydroxide electrolyte does not change. Falling hydrogen pressure indicates remaining battery charge.
The system tolerates overcharging provided the consequent heat dissipates. Self-discharge is rapid, reaching 50% in three days, but slower at lower temperatures. This arrangement worked well for the Hubble Space Telescope in daily sunlight in dark space. The satellite’s original nickel-hydrogen batteries provided 19 years of faithful service, before they were replaced during a routine service call.
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The Kordesch Hydrogen Fuel Cell
