Bike Light Battery Box

Background

Some years ago I bought a light for my mountain bike, and got many great night rides out of it. Eventually though, the battery died and couldn't be recharged. By this time the manufacturer had disappeared, so I couldn't get a replacement battery. So the battery was disposed of, and the light went into a box.

I never replaced that light for fear of the same thing happening - that the battery would eventually die and I wouldn't be able to get a replacement.

Recently though, I had an idea, so I went online and bought a stock 4-cell, 7.4V Lipo battery pack. Then I designed a box to house the battery and attach to my seat post with clamps. This box is an improvement on the original, that had to be tied to the bike with a Velcro strap.

Printing

Print out all four parts. You shouldn't need supports, but I'll leave that up to you. I printed this on standard 0.2mm layer height, on my Ender 3 Pro.

Additional Components

You'll need the following additional components to build this box (batteries not included):

• A rubber grommet for the bottom lid to feed the cable through
• Two clamps to clamp onto your seat post (or wherever else you wish). The clamps I used are often used to mount an additional bottle cage under your saddle

Assembly

With all the parts printed

• Insert the rubber grommet into the Bottom cover
• Put both covers onto the Box
• Take your seat post out and install the two clamps
• Loosen the clamps and position them to align with the ears in the two covers, then tighten.
• Remove the box and covers from the clamps to finish installing the battery
• Remove the top cover and feed the cable though the bottom cover before tying a knot for strain relief.
• Solder the battery pack's cable (a better idea could be to use some sort of removable connector) to your lights supply cable
• With all the cables in place replace the top cover and ensure that everything is nice and tight. You shouldn't need any glue, but if you do, consider only gluing one side so that you can still get the battery out if needed.
• Reattach the battery box to your bike.
• Ride!

Conclusion

I printed this item with natural color PLA and it looks really nice. It might also have been nice printed in black, but I like the semi-translucent effect of the natural filament. At some point I may make an improvement to move the cable hole off to one side, so that it isn't directly above the mounting screw of the bracket.

Print Settings

Printer Brand:

Creality

Printer:

Ender 3 Pro

Rafts:

No

Supports:

Doesn't Matter

Resolution:

0.2

Infill:

20%

Filament: CCTREE PLA / PLA+ Any