Maybe a general alternative for those who do not drive their xfire's somewhat regularly and only used them in the warmer months is to install a HD disconnect switch as I have indicated in my post #13. Doing this would allow considering a lower cost battery to be used. I do not recommend using the on-off screw type disconnect that attaches to the battery post. The recommended HD switch will make long term storage very simple and safe. As an option, a battery tender can still be used to help keep the battery at peak power.