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Old November 19th 05, 09:47 PM posted to rec.radio.amateur.homebrew
xpyttl
 
Posts: n/a
Default Trickle Charge Battery

Although most posts have suggested what you are thinking of is a deep cycle
marine battery or similar, you might consider using an SLA for your purpose.

SLAs will probably be more expensive, per amp-hour, than a marine battery.
However, most lead acid batteries are intended to be operated outdoors.
SLAs are a lot more housebroken.

With an ordinary lead-acid battery, you have two problems. The obvious one
is leaking acid, which could be a real problem in the house. The other is
outgassing hydrogen. Hydrogen is extremely easy to ignite, and if the
concentration gets within the flammable range, it will almost certainly find
an ignition source. Outdoors it is pretty tough (relatively) to get the
concentration high enough to burn, but not so indoors. Hydrogen burns very
quickly, so the result of a hydrogen fire, even in an open space, is often
much like an explosion. The good news is that is has relatively little
energy, so while it burns very hot, it tends to be over with very quickly,
so it is (relatively) unlikely to ignite things around it. Still, I'm not
the biggest fan of indoor explosions .. at least in my house.

With SLAs, neither the hydrogen nor the acid gets out, so they are a little
more friendly indoors.

...

"west" wrote in message
.. .
I know this question has probably been beaten to death, nevertheless I hope
you will still indulge me.

During a power outage, which occurs frequently in Florida, I would like to
use a battery to power some communication gear. Although the battery is
12v
and not 13.8v, I think that the gear will still work OK (hopefully).

Question 1. I believe that car batteries have a low internal resistance
because their primary function is to provide a lot of current for a short
time. There are other 12v large battery types that will last as long as a
typical car battery. They are designed not to provide peak current, but to
supply steady state current for a long time.
For the life of me, I can't remember the name of those type batteries so I
can't do a google to find a supplier. I hope this is making some sense.

Question 2. Where can I find articles & schematics for a solar cell to
provide a trickle charge for the aforementioned battery?

Thank you very much.

Cordially,
west