My battery is in the rack trunk, wrapped in a plastic bag with a zip tie around the wire (mine is 1st generation with a non-waterproof battery). It plugs into a Y cable zip tied to the rack, the taillight excess wire is in a small loop zip tied to the rack, the headlight cable is just secured along the top tube with electrical tape (I have a black frame).
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Work: the 8 hours that separates bike rides.