I was getting a couple 1/2 days and had a bit of battery left pesting pigeons and doves. Have the ABL and remote but have not used the remote yet. Reason, I set the scope on 40 really 38 yards and used the mildot for hold over as the number of targets were too many coming too fast to use the system. I would feel near 18 hours as a good estimate, if not a small USB power cell would work. Having pested a bit I feel the scope is a better bench gun with fewer targets than a carry around with the ABL. Other thought is use the bino bluedot range finder for target acquisition too transmit data to the scope for processing. Although the remote attached to the side of the gun might be OK as my biggest problem has been holding the gun, reaching up, finding the button while on target for ranging while is staying on taget.