We are often asked if you need a special charger to charge an Odyssey battery. The answer is no*. Yep you saw it the asterisk "*" They are normal MODERN DAY chargers with switch modes that best meet the needs of charging a lead-acid battery. They use preset voltage and current limit factors along with time sensitive modes to ensure they aren't over charging or harming the battery. And more importantly we size a charger so you know it will be able to recharge the battery if it goes flat overnight. If your battery goes flat over weeks or months, you need a maintenance charger once you have recharged the flat battery. So to cover both situations our range of chargers can do both "recharge" & "maintain".