batteries in my down tube

I'm thinking I would like to fill my down tube with a battery so that I could run lights and satnav and maybe even a heated saddle for cycling in the lovely Scottish winters.  Does anybody know where I could source suitable batteries?  Thanks

crapflinger5 years ago
your first step should be figuring out how much juice all of the accessories you'd like to have will need. then you can start investigating what kinds of batteries are capable of supplying that juice.
jim_20005 years ago
I've mounted batteries in an old water bottle and attached it to the frame via the bottle cage. An 8 AA holder works quite well in a large mouth bottle.
kwschofi5 years ago
Consider using the seat tube instead of the down tube. Seems like you may be able to access the seat tube for battery access by simply removing the seatpost. You could even route the battery leads up through the top of the seatpost and under your seat for recharging. The battery pack or the frame should be sealed to prevent moisture and the wiring should be well protected to prevent grounding to frame materials.

Packing all the batteries in the seatpost itself would be slick, but batteries can be heavy and your bicycle's overall center of gravity will move up.

I'm not sure what batteries would work best... you will have to measure the inner diameter of your bicycle tubing and find a battery with a close outer diameter match. I would make a protective sleeve that would fit over the batteries to protect the cells against vibration damage and grounding.

Last year I recall some conspiracy theories about Tour de France riders fitting their bicycles with batteries and drive motors... maybe do a little digging and see what you can come up with!

Good luck!