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Faster better cheaper..... Lithium ion batteries. 1

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Interesting. We'll see whether reality lives up to the hype in a couple years.

If it does, I imagine there will be a real shift to using these.

Patricia Lougheed

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Could be very interesting.... submarine batteries.... no more all nighters on the surface charging batteries....
Maybe if they can take a rapid charge they could be used to buffer wind turbine energy...

JMW
 
One of the problems with rapid charging was pointed in one of the ancillary articles; most systems' power infrastructures are not capable of providing power for doing rapid charging.

Let's say it takes 216 MJ to go 200 miles, and you want to recharge the battery in 5 minutes; that would require 720 kW usable charging rate into the battery, which is a non-trivial delivery rate.

So, for small batteries, like for iPods and smartphones, no problem.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
submarine batteries????

Do modern submarines have batteries? Well maybe from third world contries, but the rest of us I believe use reactors to make steam.
 
There are lots of "modern" submarines that use batteries, since not every country or organization is capable of fielding nuclear subs. Drug runners routinely buy or build diesel electric drive subs that use batteries when fully submerged.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
Nuclear subs have batteries - lots of batteries.

David Castor
 
I can see fewer hours on the surface charging batteries but the charge rate will probably be limited by the capacity of the diesel generators rather than the batteries ability to accept the charge.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Yes, but if you have faster charging batteries, won't you revamp the generators?
The over-riding concern would be time on surface.


JMW
 
No, for diesel electric subs, the majority of time is spent on the surface, because the battery capacity is insufficient, not because of the charging or discharging rates. The inherent energy density of batteries is lower than the fuels normally used for propulsion. That's why typical EVs are limited to a couple hundred miles, while gas-powered cars can do several hundred miles.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
And they can travel faster on the surface when using diesel propulsion.

rmw
 
Mike, that's a nice link.
I especially liked the comment:
In a carrier-dominated Navy, he knew there was no chance that funds would be appropriated for such a radical purpose. But he also knew that carrier admirals feared submarines. And that was the leverage he used. He submitted his proposal as a target for submarine hunter-killer groups to practice on. Approval was immediate.
Click to expand...
Very Sir Humphrey style thinking by Admiral Momsen.

JMW
 
The Sub Service seems to attract or breed leaders with style.



Mike Halloran
Pembroke Pines, FL, USA
 
Yes, but if you have faster charging batteries, won't you revamp the generators?
The over-riding concern would be time on surface.
Click to expand...
Just increase the size and weight of the engines and generators until you run out of space and/or buoyancy. They may be close to the line already. There is not much spare space or buoyancy in a sub.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Even if you had the generator capacity, which you do, going to the surface is a nontrivial task. Blowing ballast, setting planes, starting the diesel engines, charge for 10 seconds, shutting down the diesel engines, blah, blah, blah...

End result is probably a half hour affair to charge a battery for 10 seconds.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
Contingency planning.
Yes, the idea may be to run on the surface at night for maximum distance. But if early on in the run you get bounced and have to dive and run submerged, I'm pretty sure everyone would be happier knowing they have the maximum charge possible in the shortest time.
Plus, if you can cut the generators off line, you should be able to squeeze a bit more speed out of the boat. Yes?

JMW
 
PS, by the way, this being the UK military I suspect much of the military interest so far has been in making the squady's life a bit easier so submarine batteries may be far off and its just my throwing out an idea that may be way off beam.

JMW
 
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