Makita - Activ Energy (Ferrex) 18v battery adapter

thingiverse

This is a battery adapter that allows for using an "Activ Energy" (Ferrex) battery on Makita 18v machines. Background: ========== Activ Energy (Ferrex) 18v batteries are less than 1/2 the price of a Makita battery with equivalent capacity. Ferrex use samsung cells, so the quality is also reasonable. e.g. Ferrex 18v 2Ah: 15€ on Amazon vs. Makita 18v 2Ah: 35-40€ Remark: ========== The Activ Energy battery is rated with 20V (max). Actually this is misleading, because thats the max. initial voltage. Usually, Li-Ion Cells per definition have a nominal voltage of 3.6V. Thus 3.6V x 5 cells = 18V, which is also true for the Activ Energy battery. Additional parts needed: =================== * 4pc 3x15mm screws * 0.8-1mm metal sheet for the two conductors Making the conductors: =================== Cut the metal sheet according to the dimensions in the figure. You may use a Dremel or CNC cutter, etc. Use a vise and hammer to bend the pieces. On the Makita-side of the adapter, I bent a slight kink into the contacts to ensure a reliable electrical connection. Note 22.07.2021: I got a comment from a maker that had a different polarity on his tool. Please check your polarity first with some wires, before making this adapter. (Btw, do not short circuit the wires, as it will blow the fuse in the battery!) Disclaimer: ========== * LiIon-Batteries are delicate and potentially dangerous parts. **Use the battery adapter at your own risk!** * Use an Activ Energy charger for charging the Activ Energy battery! * The adapter is not accounting for any battery management happening between machine and battery! * Akimakes cannot be held responsible for any consequences arising from using the adapter. * The adapter was tested on the Makita vaccum cleaner only, where it worked flawlessly. Not tested on other Makita machines.