I recently went out for a 7 day outing and took a few alkaline batteries with me along with the 5000mah rechargeable batteries, charged when I left home but went flat quickly , so they may take a few charges to get back to normal, had 4 rare aldi rechargeable , they lasted about 3 hours but they are only 300 mah, the alkalines are useless, lucky to last 2 hours , they still show voltage of 1.2 to 1.3 volts but don't crank the SDC 2300 over , perhaps its the amps needed, so overall I used 48 alkaline energised batteries , aldi, sony, panasonic kodak and duracell, still got em for other electronics but went to jay car to invested in a set of batteries in desperation but they were only 4500 mha , we shall see how they perform against the minelab rechargeables and the set of 4 will set you back about $60, a day in the bush detecting is better than 2 hours in the bush learned the hard way thought that 4 x 1.5 volt batteries had an edge on 4 x 1.2 volt rechargeables , perhaps Jaycar should stock the minelab batteries as they sell the cheaper range of minelab detectors