A riding lawnmower with a chassis having a rear portion with two rear wheels, and a cutting blade deck having one or more rotary blades. Batteries are positioned in a U-shaped array around the right side, left side, and rear end of the chassis, above and near the rear wheels to maintain a low center of gravity. The weight of the batteries is evenly distributed over the rear wheels to maintain balance. The batteries are connected in series to each other and to an electric motor. The electric motor is positioned within a central portion of the U-shaped array of batteries. A single electric motor drives both the rotary cutting blades and the rear wheels, which is made possible by placing the batteries near and above the rear wheels, and by positioning the electric motor under the seat.