Digital Concepts Extended Life Battery for NB-4L. With 850MAH (vs Canon's 760MAH),this battery lasts 33% longer than the Canon NB-4L! So now you can shoot longer before recharging! This high-capacity rechargeable lithium ion battery has more power than the original manufacturers included battery. It features Lithium technology, which ensures maximum battery life and maximum power. It also features No Memory Effect that lets you recharge partially drained batteries without reducing performance.