Energizer E2, 2CR5, 6V XL lithium photo battery. 6-Volt e2 Photo Lithium Battery is designed for use with cameras, photoflash, calculators, pocket pagers, watches, memory backup and other high-drain applications. 6-Volt e2 Photo Lithium Battery performs even in extreme temperatures. Storage life up to 10 years. 6-Volt e2 Photo Lithium Battery is designed for use with cameras, photoflash, calculators, pocket pagers, watches, memory backup and other high-drain applications. 6-Volt e2 Photo Lithium Battery performs even in extreme temperatures. Storage life up to 10 years.