I have an older (1997) APC BackUPS Office surge suppressor/ups. Its single 12V sealed lead acid battery has died. I also have a motorcycle and a car that I don't ride or drive during the winter, whose batteries have been pulled.
My question is:
Can I hook up the car (or motorcycle, obviously not at the same time) battery to the 12V battery leads in the UPS (presuming I can make some connectors) and plug in the AC cord, to keep the battery charged/topped up? Are the technologies between the UPS battery (sealed lead), the motorcycle battery (non-sealed lead) and the car battery (non-sealed lead) different enough that this is a futile or dangerous task?