The NP-BX1 Rechargeable Lithium-Ion Battery Pack from Sony is designed to replace the original NP-BX1 battery that arrives included with the Sony DSC-RX1 and DSC-RX100 digital cameras. It is certified to be compatible with the original Sony charger and camera. Smaller and lightweight, Lithium-ion batteries can be charged or discharged at any time without developing memory effects.