Rather that the older and less reliable NiCad batteries, we found a handy charger from Duracell that uses NiMH (the type of battery used in a mobile phone). The charger is the Duracell Rechargeable Value Charger. This comes with a pack of 4 AA 1.2V Alkaline batteries rated at 1800mAh. The charger, plus the 4 batteries. As the mAh on the rechargeable batteries is lower, we need to find out how many charging cycles will be needed to get the same consumption as 25. Winner: Rechargeables: You'll be better off after just 5 charges Our Pete's done the maths. For charging 4 x AA batteries 30 times, you'll pay less than 10p. With the cost of the rechargeable batteries and the charger, the total is. Thanks to Michael Lees for the following question on rechargeable batteries vs conventional batteries: Here's our (rather limited) understanding: There are two types of rechargeable batteries – the older NiCad (now being phased. Thanks to Richard for the following: Thanks to another Richard, Richard Paice, for this: Also thanks to Rob Dickson for his observations: Got a.