I've got 8 Aldi AA batteries for my metal detector - they work fine, although I think the voltage is a little less than single-use batteries, which can be a problem with some LED torches etc (might be 1.2 instead of 1.5 volts). Got a cheap Digitor battery charger from Jaycar, leave them to charge overnight, no problem. Good if you are a long way from any shops - just recharge and keep going.