14.4 V Li-ion battery pack

thingiverse

With this thing, building your own 14.4 V (4S) battery pack is easy and fast. It is designed for 4 Li-ion batteries of the 18650 type and thus capable of about 3000 mAh capacitance at a mass of only 260 g. In many applications it can replace a significantly heavier Pb-acid 12 V battery. As the battery management system (BMS) is built in, there is no need for a sophisticated charging mechanism. In addition to the two printed parts you will need: 4S BMS 2*4 battery clips 4 Li-ion batteries 18650 4 self tapping screws 2.9 x 9.5 mm wire 1.5 mm2 and 2.5 mm2 Total material costs should be well under 30 € and building time is about 1 1/2 hours. There are comprehensive building instructions available at http://www.oe1cgs.at/144-v-li-ionen-akkupack/ (german, but many pictures) which include sources. Please see also my related design at https://www.thingiverse.com/thing:3136181