OM System BLX-1 Battery For OM-1 Mirrorless Camera Rechargeable Design 7.2V Output 2280mAh Capacity The BLX-1 Lithium-Ion Battery from OM System features a capacity of 2280mAh and provides 7.2V of output power. Small and lightweight, lithium-ion batteries can be charged or discharged at any time without suffering from memory effects.