Ive seen both, the real shaker flash lights use a supercap to hold 5v @ 1farad or so, and have a bridge rectifier from the coil etc.. like you would expect. The knock offs from china contain a coil of magnet wire, just one layer typically, which in the one Ive seen both leads were soldered to the same pad on the pcb, and there was still 4 diodes, hooked up to nothing, and 2 2032 coin cells stacked where the cap would go. The knock off ones are cheap, the legit ones are pricy, as you would expect. (guess that super cap and all that copper for the coil adds up...) -Jon On Mon, Nov 16, 2009 at 5:57 AM, Jinx wrote: > > A question for the battery experts > > Well, thanks for that ;-) > > > What type of batteries is commonly used in "battery-less" flashlights > > I've a Faraday LED torch that is supposed to be battery-less but does > in fact have a 2023 coin cell hidden in it. So for the first few hours it > works well and you think gosh I'm a good shaker. Then the battery runs > down and she no work not so good no more. It still makes light but > the "supercap" storage isn't what you'd hope or expected > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist