[PSUBS-MAILIST] Air comp battery compartment

[Sean T. Stevenson via Personal_Submersibles]

I have no specific experience with this, but my first thought is to wonder whether dissolved oxygen would present a problem, if you are air compensating in direct contact with the battery electrolyte? Nitrogen doesn't dissolve readily, but oxygen does, and particularly at low temperatures and high pressures. When that gas subsequently evolves out of solution when the pressure is reduced, will it nucleate on the battery electrodes / plates and consequently reduce efficiency / capacity? If I were going to gas compensate, I would use nitrogen or argon as opposed to air. At least with oil, the oil should remain imiscible with an acidic aqueous solution electrolyte. Much less complicated too, being effectively incompressible. The required compensation volume is minimal and can be provided with a simple membrane or local compensator. With gas, you need a high pressure supply and a pressure reducing regulator, which must be self relieving, or you need an additional vent. The only thing you really avoid going with gas is the mess and the risk of environmental contamination.

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-------- Original Message --------
On May 25, 2019, 07:34, Jon Wallace via Personal_Submersibles wrote:

> Any reason not to?
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