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.