Stay up and running with Energizer Industrial Alkaline D Batteries, designed to provide an economical power source for modern devices that require high power input and frequent use. Energizer D batteries are designed to provide long-lasting power and to meet heavy current and continuous use demands of all kinds of devices. These batteries operate well in extreme conditions and readily perform even after five years of storage. Each battery provides four to nine times more energy than similar sized carbon zinc batteries. Energizer D batteries do not contain mercury.