Amazon.com: 12 Volt 12 Amp SLA Battery - MK Battery 12V 12A Rechargeable Sealed Lead Acid Batteries - For Peg Perego, Ride On Cars, Currie, Ezip, Izip, Razor, and many 24 Volt
MK Battery 12-Volt Heavy-Duty Power Equipment Battery in the Power Equipment Batteries department at Lowes.com