Yeah, the intelligent one is the way to go, but if you want cheap, I have an 8.4V 250mA trickle charger with small Tamiya connector and two pin configuration (so it needs 1 of those foreign plug / shaver adapters). You can have it for £5.50 posted 2nd Class Recorded, but if you want it, you'll have to say so and paypal me before 11:30am because I'm going away from home today for maybe 10 days.