As Steve says, but there's more to it than just getting a battery. You'll need a charger for the battery, something like Amazon.com: 14.6V 10A LiFePO4 Battery Charger Special for 12V LiFePO4 Battery, Trickle Charger for Lithium Iron Phosphate Battery, Battery Maintainer, Built-in Safety Protections, Support Fast Charging : Automotive along with the crimp tools for the connectors. You'll need a couple of crimp on connectors for the battery. They'll need to be .250 inches wide for an F1 tab. Quicksilver Radio will sell you a premade power pole connector for the battery box Play-Series™ Powerpole Mount.