The high-capacity BP-31 Rechargeable Lithium-ion Battery for Sigma DP Series Digital Cameras from Sigma is compatible with the Sigma DP1, DP1s, DP1x, DP2, DP2s, DP2x Digital Cameras, and 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.