I just got an AGM battery this year. I know they are good at holding up to the cold, but I tend to over think things so I need to ask. In the winter I put my plow on and leave the ATV outside. Even though I have an AGM battery, should I still take it off the ATV and only put it on when I use it or is it fine just staying on the ATV? Someone suggested that I leave it on the ATV and just put a Battery Tender on it. I need suggestions please.