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by HWR_14 1001 days ago
As I understand it, something like a lead-acid battery using volumes of acid and volumes of reactants so a cube gives them more power with the same surface area. NiMH batteries use boundaries between states instead of acid. Therefore, you want long thin batteries of alternating materials to make them more efficient.

Or, to put it a different way, NiMH batteries require a large interior surface area, and so the square/cube law forces them to look longer and thinner as they get larger.
1 comments
h0l0cube 1001 days ago
As per the article, these Nickel Hydrogen batteries are very different to NiMH

> Nickel-hydrogen batteries look and work unlike any other battery. They consist of a stack of electrodes inside a pressurized gas tank. The cathode is nickel hydroxide while the anode is hydrogen. When the battery is charging, a catalytic reaction generates hydrogen gas. During discharge, the hydrogen oxidizes and converts back to water.

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HWR_14 1001 days ago
Sorry, yes. I was, however, describing my understanding of Nickel Hydrogen batteries' relationship with the square-cube law. Not NiMH.

See this diagram: https://en.wikipedia.org/wiki/File:Nickel-hydrogen_battery_N...

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