batteries

A thread of 2 messages, 10 April 1991 to 11 April 1991, in the order they were sent.

#2264 batteries

	I have somewhat of a vested interest in knowing about batteries, since
I'm doing the electrical power subsystem development work for groundbreaking
work on Mars environment spacesuits with NASA 8-)

	The apollo suits used rechargable (but not recharged) batteries with
a power density of close to 200 watt-hours per kilo.  This corresponds very
well with the listed TL6 battery (exactly, as it happens 8-).  I don't know
about rob dean's Cr to $ conversion, I always used 1:1 myself for most things.

	Future developments are expected to give up to 6-900 watt-hrs per kilo
in the next 10-15 years.  The best ones we have now are about 400 watt-hours/kg.

	My guess is that the TL5-9 numbers are accurate.  Above that, I can't
hazard a guess.

	I agree that the listed control point values are out of control.  I
would suggest that a battery need only about 0.1 CP per ton, and that any req's
under 0.1 CP be ignored. 8-)

- - -george william herbert
[email removed]

#2271 Re: Batteries

I assume that the reason that batteries are not considered seperately in the
control rules is that no section is considered seperately. One would presume
that every section and several sub-sections would have its own multiplier to
the control point calcualtaion. This would make designs much more complicated
and I believe that they wanted to keep things simple.
In most cases I'm sure that the CP calulation is correct (averaged over the
entire vehicle). But I can come up with some other examples.
1a) Jump drive is incredibly complicated when it is running, but simple at
other times, perhaps one can calculate CP like energy, and determine
peak requirements.
1b) Jump drive should be far more complicated than maneuver, but they cost
almost equivalent.
2) Cold sleep equipment is cheap, but would require much more control than
the average stateroom. Maybe there is some amount of local control assumed
to be built into each cold sleep berth.
3) Why are we required to use the crentral computing paradigm? Why not
have a network of smaller computers to provide the functions of the main
one?

			-Dan

Dan Corrin, Network Manager, Mechanical Engineering, UWO, London, Ontario
TML/CZ FTP site coordinator:     [email removed].        [phone removed]