Recharging and Testing 12V Batteries
If you've purchased a UT 1300 12V lithium ion battery (or any sized12V battery for that matter) - eventually you're going to need to recharge it.
Another good solution for regular use, for those on the go or for emergency preparedness is the Noco Genius 10.
If you're simply interested in knowing "how much battery is left?" - the Antigravity Battery Tracker is a good choice.