Nords, why don't subs have fuel cells instead of batteries? Seems like it works for the space station it should work in the confines of a sub. Just curious. Could it be lead acid batteries are cheap, and the sub has to be a certain size anyway. Lord knows they would not use the extra room for crew bennies. Although my BIL says boomers are quite roomy.
Good question. Some European sub classes are probably using fuel cells as part of their air-independent propulsion systems, but conventional subs tend to have much smaller displacement/propulsion parameters than nukes. I haven't kept up so I don't know the issues.
I bet it's an issue with discharge rate & capacity. After a reactor scram it's not unusual for a LOS ANGELES storage battery of 7000 amp-hour capacity to be discharging at a 4000 amp-hour rate for 10-20 minutes (longer if it's a bad time or a slow crew response). I've had to live with older (near-death) batteries hitting their safety/performance limits where the only other option was to have the Electrical Operator "help" rig the whole ship for reduced electrical by dropping a non-vital bus or two from his panel. That threat gets the crew moving faster next time but it's hard on electrical equipment (and, after watch, on Electrical Operators). I wonder if fuel cells could be abused that hard, and I don't know how they'd be recharged onboard. Although the oxygen generators cough up plenty of hydrogen byproduct, so that wouldn't be an issue.
As M Paquette already mentioned, cost is certainly the deciding factor. Lead-acid is cheap. Unlike quieter propulsion or more powerful reactors, I don't think there's been any compelling reason to change the ol' reliable battery system.
Today's boomers have a lot of space by virtue of their loadout. The older 16-tube boomers weren't much roomier than the attack subs, but the OHIO class subs (with 24 tubes) have more internal volume than the crew can keep clean. We actually had guys transfer from boomers to attacks just to get away from the constant punitive cleaning.
I think the biggest "manhood" difference between today's attack subs & boomers is that the LOS ANGELES-class subs have sanitary tanks capable of being pressurized to test depth, which meant that the toilet flushing valves were made of high-strength titanium & stainless steel. OHIO naval architects managed to save tons of money by developing a boomer sanitary system that wasn't subject to sea pressure, and so they installed porcelain toilets instead of stainless. The manly attack sub crews tease the soft wimpy boomer crews about this, but it's really thinly-disguised jealousy.
There's a huge attitude shift between being a steely-eyed roving predator of the deep versus a quiet bunny rabbit who can hide with pride. I'm glad I [-]served my time[/-] had my boomer tour when I didn't know anything better existed. The minute I went to sea on a fast attack and cranked it up "greatly in excess of 25 knots" I knew I couldn't go back to boomer world. And when the Cold War ended, I don't know how the boomer guys managed to maintain the will to live. They probably had to keep reminding themselves that they were doing it for their family's quality of life, but it's like trading in a Ferrari for a big golf cart.
