Have to admit, c5 without battery is quite nice to pedal (not for long)
Pedalling a c5 with two batteries wasnt fun at all..
Like Umpa, always carry adequate spares if you can. c5 toolbox, pump and puncture repair kit are a must.
Carry spare Inner tubes if you can.
I have considered carrying one of those spray cans of crap that you pump into the tyres on cars.. Not sure how good that would be though! (Saying that, it might be totally brilliant, if expensive!)
Also I try to go out in two or more and dont get lost