Nothing outlasts Energizer Ultimate AA Lithium Batteries. The Energizer Ultimate Lithium batteries are the #1 longest-lasting AA batteries complete with leak resistance and performance in extreme temperatures (-40ºF to 140ºF or -40ºC to 60ºC). To ensure your favourite devices operate at their peak performance, depend on Energizer Ultimate Lithium batteries for work, play and home. They are commonly used for: Outdoor and Tactical Equipment: Devices like GPS units, tactical flashlights, and other outdoor equipment that may be exposed to harsh conditions often use lithium AA batteries for their superior performance in extreme cold or heat. High-Performance Digital Cameras: Professional and high-performance digital cameras, especially those used in cold environments, benefit from lithium AA batteries due to their long life and reliability under burst shooting conditions. Emergency and Safety Equipment: Lithium AA batteries are commonly used in emergency beacons, smoke detectors, and carbon monoxide detectors for their reliability and long shelf life.