I'm not sure I would keep the tender on it 24x7. There are some good ones and some bad ones. I know of someone who has wasted two airplane batteries in the last two years. However, if it's not a cheapie, I would keep the battery OFF of concrete and NOT where it can freeze. Put the tender on and every month or so, check to see if the battery is warm. If it is, take it off the tender; it is overcharging.

The best way to store a lead-acid battery long-term is to remove the acid, but I don't recommend it.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)