Tom Walker wrote in a message to Roy J. Tellason:

->  TW> Adn incideltly a Gell Cell is a Poor Battery to pick fro a possable
->  TW> deep discharge operation. A Wet Cell is far better suited.

-> On what do you base this?

TW> Manfacturers Specifications. I have delt with Gel Cell batteries in
TW> Critical Medical Equipment. They specificly spec NOT deep 
TW> discharging them on a regualr basis.

Oh.  Perhaps what you were reading there is a warning against the sort of
treatment that some people have figured as being "necessary" with
nicads,  to prevent the "memory effect".  I've seen people do
that,  and gel or wet,  deep cycle or not,  it's a good way to ruin a
lead-acid battery.  The way to treat those is to keep them nearest full
charge for as much of the time as possible.

-> TW> Incideltly I had the same thoughts as you. But I picked a Laptop as
-> TW> the  Computer and use a 205 Ah Reserve capacity Size 31 Deep
-> TW> Discharge rated Wet Cell for my Battery. That calculates into
-> TW> nominaly 225 Continious operating Hours before recharging.  :-) 
-> TW> :-)

-> Hm.  I hadn't seen any group 31 deep cycle batteries,  most of them 
-> were either group 24 or group 27...

TW> You corner autoparts store typicaly dosen't carry them.

I wouldn't even think of going there for a battery.  Those place will let
something sit on the rack for a period of time,  and when the date code
hits six months or longer,  they send it back to their warehouse (!) for
recharging!  The same is true of those racks you often see in service
stations.

No,  I _managed_ a retail battery store at one point (January of 1993 to
about October of 1995),  and was pretty familiar with a lot of stuff.

TW> But if you ask most can get them for you. They are carried by 
TW> Marine Supply stores and RV stores though.

I'm not sure without looking at specs that there's that much to be gained
with a 31 over a 27.  Though I did have a 31 in my one truck...

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