a slight misunderstanding , a ups is a safety powersource used to keep computers running when the electricity net fails
try looking ups up on ebay , and you will see what i mean.
i have had no problems using a ordinary charger,
the advantage of a sealed battery is it keeps its charge very well,
i have left a sealed battery unused in a bike for a year, and could still start the bike.
so i didnt need to charge it often.