Winter biking can be excruciatingly uncomfortable in Ithaca. (It can also be dangerous—see Making Winter Biking Safer.) This winter I developed two bike accessories to combat the cold: electric bike gloves and a bike canopy (which is still in development).
If I bike an errand longer than a few miles and the temperature is in the teens, my fingers and toes tend to go numb. Numb is okay until I stop and warm up; I then become doubled over in pain as my extremities thaw. I’ve tried all kinds of gloves to no avail. And I discovered that if I wore several gloves at a time my fingers still got cold because their circulation was lessened. Finally I hit upon the idea of using electric socks and glove liners. Personal electric power is just one of the many design opportunities presented by electric bikes that have yet to be explored (while the transportation industry wastes their time with stupid technologies like hybrid cars and hydrogen power). The electric socks and glove liners I bought (from Brookstone) were powered by a total of 12 AA non-rechargeable batteries that you had to strap to your limbs (three batteries for each limb). I realized that with a little inventiveness I could power them all with the bike battery instead.
Using the bike battery required figuring out how to get the electricity from the battery to my extremities. First I lined my coat and some snow pants with wiring using safety pins, and then I added Anderson connectors and a central connection block. Anderson connectors are a wonderful kind of connector for inventing things. You can just crimp the wires on and then snap together as many connectors as you need.
I also needed some way to step down the voltage from the battery’s 36 volts to the electric clothing’s 4.5 volts. I found that ebikes.ca sells such a converter especially made for electric bikes. (These are the same folks that made my front and rear LED flashers.) A word of caution: I learned from experience that if you plug the converter in backwards sparks will shoot out of it. However, it still works! I marked all my 6-volt connections with purple tape.
Finally I wanted an easy way to connect my clothing to the battery as I got on and off the bike. I expected that some sort of slick magnetic breakaway connectors like the ones Macintosh computers have would be available. There was nothing. Two possibilities—the Belkin BreakFree or Replay breakaway headphone adapter advertised in 2007 and 2008—are nowhere to be found. I suspect that Apple has a patent on magnetic breakaway connectors that is preventing others from selling them. So I ended up just using my Anderson connectors.
The results: after some trial and error it worked. One problem was that the wires I used were old and they broke a few times. (Once my left foot suddenly grew uncomfortably warm while my hands suddenly became cold.) Also I was nervous that I might damage my expensive LiPoFe4 battery. It is true that LiPo batteries can be damaged by either too much charging voltage or dropping too low in voltage. However, most of them also have very sophisticated battery management systems built in to prevent this. Finally it was too inconvenient to attach and detach the wires all the time so I started using an old NiCd battery instead.
Next year maybe I’ll explore some alternatives such as handlebar muffs or windscreens or heated handlebars grips. I wonder if it’s possible to find flat wiring that you can sew into a garment. And here’s another design opportunity: one problem with biking in winter is that you are too hot on the uphills and too cold on the downhills. With electric garments you can control the heat. One way to do it is that you could have a clutch to spin the motor on downhills and switch on the garment connection. Or you could use the computer to sense your speed and switch on the garment connection when you are going over say 15mph. I’ll keep you posted.