12V 18 AV li-ion battery 199 Wh Small and lightweight 12V18 battery. Ideal for smaller fish finders and carp fishing. This battery operates at 12 volts and has a capacity of 18 Ah (amp hour). The battery is completely maintenance-free and has as many as 1000 charge-cycles. That means 1,000 charges and discharges. It is significantly lighter than a comparable lead battery and has a much lower annual loss. Thanks to the built-in Battery Management System, you never have to worry about discharging the battery too deeply and damaging it.