Ions use lithium batteries too. I lay mine on the ice, battery up, in front of a shanty window with the battery attached just like I did my gasoline Strikemaster for 20 years. I've still never had a battery issue. I bought the little battery lunch box gizmo thinking I'd need to use it with some hand warmers to keep the battery up. It was a waste of money and it's laying in my shanty now just taking up room and adding weight. I think I'll pitch it unless there's a sucker here that wants to buy it!