Duracell Rechargeable Pre-Charged NiMH batteries let you charge hundreds of times, helping you save money With its Long-Life Ion Core technology you get amazing power in every battery. Plus, they come pre-charged and ready to use. They are guaranteed to last for 10 years* and they will hold a charge for up to 1 year when not in use. These powerful NiMH batteries work in any NiMH charger and you can recharge them up to 400 times