Originally Posted by
noglider
Yes, they are not suscepitble to cold. The problem is not the light, it's the battery. I usually ride one of my dynamo-equipped bikes, and the light works 100% of the time. If you haven't read it yet,
here is my post on my system on my Bianchi. I installed it about two years ago, and it just keeps on working. I run it day and night.
Yeah, just to agree, I ride in the winter in Minnesota, my dynamo light always works.
I think the limit for electronics that aren't specially made is around -40f, so if you ride in conditions that cold or worse I'm not as sure.
I wouldn't normally expect as drastic of a drop in runtime as the OP is saying from a lith-ion battery though. The runtime gets a little shorter in the cold, but it should not be getting that much shorter.