Originally Posted by
ThermionicScott
Not a bad idea to just buy another charger and leave it at work.
In winter, I generally bring battery lights indoors when I'm not riding, just so they will work better (at least until they cool back down to the ambient temp.) I'm eager to build up a dyno wheel for my fixed-gear (primary commuter) so that I will have fewer battery lights to futz with.
+1,
Also consider that batteries produce a bit of heat as they discharge. So if you insulate them with something like bubble wrap, and store them indoors, they may stay warm enough to function well all the way home.
If you opt for some kind of full time insulation of the battery case, don't forget that it might make sense to remove it in the Spring.