This battery pack was designed and built to run my compressor cooler.  I wanted a battery pack that could be carried in the back of a SxS and not worry about power cords or connectors getting broken (no cords, flush connectors). The design incorporates an open cell design to help keep the cells cool.   The design use 3mm heat inserts and 3mm bolts for a robust assembly.

The pack will easily power my F40 cooler for 8 hours, and depending on the ambient temperature, the pack could power the cooler for a lot longer.

The pack uses 18650 cells in a 7S4P layout. The cells I used provide a nominal voltage of 25v with a max discharge rate of 20A.  The cooler only draws 45w(max) so there is plenty of power available.  I used a Daly BMS for charge/discharge protection.

The F40 cooler is impressive for the money.  I normally have it set to 38F to keep our water, sodas and beer icy refreshing.   For ice cream you can set it to the lowest setting of -8F to keep it frozen rock hard.  My cooler was able to reach -3F with an outside temp of 75F…..which is pretty impressive. 

The case is printed in ASA for outside durability but could be printed in PLA.  

I have included a step file of the model so you can tweak it to fit your needs.