Winter Storage Question

Well,as we all know,the cold weather is upon us that live in cold regions and I have a question.Im going to try and start and run my Duster as much as I can this winter but because it sits outside,is there something I can put in the gas tank this winter to keep the fuel lines from rusting and crapping out.I spent too much on a new tank,new lines for them to rot out.Hopefully this winter will not be too bad,but in Colorado,the weather is pretty unpredictable.
And I know this is the fuel section,but what about battery storage?I bought one of those small battery tenders that give a small trickle charge.Hopefully that will work.