StayCharged AA rechargeables come fully charged and ready to be used right out of the package. Long-life Ion Core packs power in every battery. Recharge up to 400 times to save hundreds of dollars. Duralock Power Preserve Technology holds a charge for up to one year in storage so batteries are ready for your high-drain or frequently used devices, including video game controllers, high-powered flashlights, baby monitors and more. Each battery holds charge up to five times longer than ordinary rechargeable batteries when not in use. Batteries work in any NiMH charger.StayCharged AA rechargeables come fully charged and ready to be used right out of the package. Long-life Ion Core packs power in every battery. Recharge up to 400 times to save hundreds of dollars. Duralock Power Preserve Technology holds a charge for up to one year in storage so batteries are ready for your high-drain or frequently used devices, including video game controllers, high-powered flashlights, baby monitors and more. Each battery holds charge up to five times longer than ordinary rechargeable batteries when not in use. Batteries work in any NiMH charger.