Water bottle battery for bicycle lights

1. Parts:

• Sanyo 20700 x 6

• 8A PCB and M/F Molex connectors

• 16AWG stranded wire

• DC extension cord

2. Weld taps on cells: for 8.4V output battery pack, three cells are bundled in parallel, and serially connected to another bundle of three parallel cells.

3. At the core, I put a 20mm carbon tube, which helps the pack maintain hexagonal shape. A PCB will be placed within the carbon.

4. Lezyne container will be used for packaging.

5. Plastic sheets for insulation of the battery pack - I picked up the plastic sheet from a recycle bin.

6. Connect PCB and connectors

7. Wrapping

8. Packaging in the Lezyne container.

9. Done. Left is the finished work and the right is the original battery pack.

12750mAh, 461g

7800mAh, 336g

Charging

Final test