Observing proper safety (ie, not using it inside the home), is there any reason using a car-sized 12v gel-cell (eg, Optima*) would be a Bad Idea (tm)?
Form-factor is not an issue; the battery would be outboard, of course.
Charging time would be much longer considering the modest charge current of the UPS, but so would be the discharge time.
Opinions?
Thanks.
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