What i mean is a home power supply, sorry i should have been clearer. Maplins do a power supply with a car accessory socket built into the case, so you can plug the angel charger directly into it (in the 2002 catalogue it's RP08J, Palstar PS-06 £34.99). There is a cheaper way, get a CB power supply and a trailing socket. You should be able to pick up a CB power supply quite cheap, and maplins do a trailing car accessory socket.
They also do a slightly smaller output one, RP07H at £24.99. For the £10 saving this is a good buy.