Nothing outlasts Energizer Ultimate Lithium 9V Batteries. These Energizer batteries last up to 20 percent longer in toys versus Energizer MAX batteries, and they feature leak-resistant construction and performance in extreme temperatures ranging from -40°F to 140°F. Use these 9-volt lithium batteries to power toys and games, or use them to provide up to 10-year battery backup in AC-powered smoke detectors. Energizer 9-volt Ultimate Lithium batteries weigh 25 percent less than standard alkaline batteries. They also hold power for up to 10 years in storage, letting you keep a ready supply of backup 9-volt batteries. To ensure your favorite devices operate at their peak performance, depend on Energizer lithium batteries for work, play, and home.