Panasonic Eneloop Rechargeable AA Battery with Low Self-Discharge BK-3MCCE (4-Pack) Recharge up to 2100 times. Maintain up to 70% of their charge after 10 years (when not it use) 2000mAh Type, 1900mAh Min, Ni-MH pre-charged rechargeable battery Pre-charged at the factory using solar power and ready to use No memory effect - batteries can be recharged when fully, or partially discharged Shrink wrapped to reduce waste