I am wondering how the internal charger would react to seeing a 110 CCA battery as opposed to the internal 9 Ah battery?
< My UPS uses an external battery. It's not of a make that anyone < here would recognize. It's very basic, rather poor in external < finish and internal construction but it does the job and has been < doing it for some 13 years.
< I use a small car battery of 35Ah capacity which gives me a good < backup time. I've never tested the backup time to its limit but < it's more than 1 hour when the battery's new. I used the first < battery for about 10 years by which time the backup time had < dropped to about a minute. The replacement cost around $50 and is < still going strong after 3 years.