>>57105251In as small of a frame as whats in the op? No, not at all.
The device shown in
>>57100955 was a device that was supposed to do something very similar iirc. Power requirements to pump around enough water to feed a electrolysis system for a single person would require a massive battery. I believe its around around 100L of water required to flow through the system every minute (1.666L per second) to sustain a single person. And there is just not enough surface area for all that water to go through. I'm as skilled or knowledgeable as the other diver anon in this thread when it comes to diving/air mixes. But iirc, 100% oxygen diving kills you pretty fast when diving. And I don't remember why.
On a much larger scale however, yes absolutely it works. Most, if not all submarines that are equipped with a reactor use electrolysis to supply the crew with breathable oxygen in conjunction to using co2 scrubbers.