I have an inova 12 volt led on my quest carbon velomobile. All you need is a LI-PO 11.1 volt rc type
battery and the li-po charger. I get a few days of run time if you run the light 4 to 5 hours a night after dark. I'm also running a whelen vertex light head flasher on the rear.

here's a short clip of the rear 12v flasher. I don't have any pics of the headlight, but you can check it out at bluevelo.com

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