Your warning about Gel cels is accurate. However very, very few UPS units
have Gel cells. Many people think they are, even those that sell them. What
most use are common lead acid cells that are semi-sealed and the electrolyte
is held in a very absorbant blotter like material. A true Gel cell will say
GELL
CELL on it.The instructions that come with replacement batteries usually say
not to chargeinverted. A Gell cell can be charged and operated in any
position.
The sealed lead-acid cells can be operated in all positions except inverted.
I see many batteries sold on eBay advertised as Gell cells but if you get
the
catalog from the manufacturer you often find that they don't make any Gell
cell batteries.

I have connected my UPS to a car battery when both had been fully charged
and checked for voltage differential before closing the circuit. I found
less than
10 Mv. difference. With about 5 feet of #10 wires connecting the external
battery I found no problems. I ran a seismograph and computer with monitor
for several weeks from it and neither battery was damaged

                   Al Allworth

----- Original Message -----
From: "Charles R. Patton" 
To: 
Sent: Tuesday, May 08, 2001 9:38 PM
Subject: Re: Gas Generator recommendations / standby power


> Al wrote:
> "I have a 250 watt UPS that I put Binding Posts on the back so I can
> add more battery capacity when needed. It uses 12 volts."
>


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