18650 Lithium Ion 4-Cell Battery Pack

thingiverse

I designed this unit to accept 4 18650 Li-Ion Cells, 2 in series, 2 in parallel, for the purpose of powering a night-light. The cable end is designed to be epoxied into place, the other end clips on and off (may require a screwdriver to pop off). This unit is designed and tested/proven to withstand popping open under extreme conditions, as I use it strapped as shown to my mountain bike frame - I downhill at night with this thing on the (in)famous north shore mountains of Vancouver, British Columbia. Vancouver is also a temperate rain-forest, so this unit also withstands a substantial amount of rain and mud. I use Orbtronic Protected Cells (https://www.orbtronic.com/18650-protected-battery-3500mah-lithium-ion), which are longer (68.9 mm) than unprotected cells.