Bicycle generators and LED lights

The link you posted looks like free site operator advertising to me.

--
 JosephKK
 Gegen dummheit kampfen die Gotter Selbst, vergebens.  
  --Schiller

["Followup-To:" header set to sci.electronics.design.] On Fri, 11 Aug 2006 15:32:51 GMT, Ignoramus16112 wrote in Msg.

[...]

At least in Germany you can't find anything BUT bicycle lights that fill all these requirements. Actually halogenics are preferred for the front light, but any decent backlight is LED (plus a gold cap to keep the light on while you're stopped). Get a generator hub for max efficiency. robert

Oh, a 12V 4AH "gel" sealed lead-acid is somewhat smaller than a usual brick and weighs close to or a little over a kilogram. That gives me hope of a 6V 4AH "gel" lead-acid weighing about or not much over a pound, maybe 1.5 pounds.

I would surely prefer to truck around a pound or a pound and a half of extra weight than drive a generator!

How about NiMH? 5 good AA cells give you 6 volts to maybe slightly more even under some load, with 2.2 AH or maybe a bit more. Moderately higher-end NiMH cells of "subC" or "sub-C" size have 3.3 AH capacity and weigh maybe 60 grams apiece, for a 6V 3.3AH battery weighing

300 grams (about 2/3 pound)! Somewhat better "C" size ones have 4 AH and weigh 78 grams apiece, for a 5-cell battery weighing 390 grams or a hair under 14 ounces!

How about Li ion? 7.2V 4 AH (four "18650" cells in series-parallel) should weigh about half a pound. Just know well the necessary protections against overcharge, overdischarge, and cell imbalance!

- Don Klipstein ( snipped-for-privacy@misty.com)

A co worker went out riding every night. I built him a dirty DC charger and he recharged his ordinary D cells repeatedly for many weeks and was well pleased. This is also done for some mine helmet lamps.