Lost All Electrics & Stalled: Any Ideas?

[SBM]

I have a 2009 2L Tdci auto. Today I lost all electrics and power whilst driving. Very scarey but managed to pull over safely. Had no brakes, power steering, lights, hazards, nothing. Effectively a dead car. This is the second time it's happened this year. I have had full diagnostic (not from dealership) and nothing was found. Today RAC guy simply moved the main power cable which comes off the battery and power came back again. He tried to make it happen again but couldn't. He suggested replacing the cable. Took it to local garage and they said cable was ok. He said the lead terminals on the battery were not connecting properly and filed them or something. Car works again now but I am very worried that it couldbe something else. If it happens on a busy motorway or in bad weather the outcome may not be so good...death trap.

Anyone heard of this happening before or agree / disagree with my mechanic? Any advice appreciated.

[STEADS]

Sounds correct I was going suggest earth related myself until I read the whole post as long as the cables are secure on the battery you shouldn't have a problem cables being loose on the battery is just like flicking the ignition key on and off basically I would look at replacing the connecting ends though if they had worked loose for whatever reason .

[SBM]

Thanks Neil. A friend recommended buying a new battery too as I think the one I have is the original which would be 5 years old now. Still holds charge but apparently could have a cracked plate inside which could cause similar symptoms. Might buy one to be on the safe side.