The Grin Tech ebike lights are designed explicitly for use on electric bicycles. They will operate efficiently with anywhere from 15V to 100V on the input. Not only can they be directly connected to your battery pack, they'll continue to work fine even if you upgrade or change your battery voltage in the future. All lights are available with 5.5x2.1mm DC input jack so they can be powered directly from a Cycle Analyst (V2.3 or newer) but some custom wiring options are available as well.
US$55.00New 200 Lumens Ebike Light, Auto On/Off, Consumes 4W, StVZO Compliant Optics, DC Jack Powers from Cycle Analyst, Handlebar Mount, 12V Minimum 75V Max,4 Watts
US$70.00Grin Tech 1 Watt 12 LED Waterproof ElectroLight with Button and Handlebar Mount. 12-100V Input R...
US$60.00Grin Tech 8 LED Waterproof Rear Electrolight with Button and Unterminated Leads. 12-100V Input R...