I decided I needed a CHEAP portable 12V power source so I bought one of those colourful plastic storage cubes from Kaymart or wherever and bolted in a 70 AH "$40 special" . I wired in a couple of cig lighter sockets through a 30 amp relay. The battery is left connected to a trickle charger when otherwise not in use...(powering a cheap and cheerful 12V cordless drill that's no longer cordless...a 150W inverter ...etc etc)


Like Ron, I disconnect the RR battery when I'm working on the vehicle. However, if I need to charge the RR battery, I simply drag out the "cube" and connect it to the RR with a cable made for this purpose which puts the vehicle on "battery bypass" no more stu$$ing around having to reset things...