I used a $20 12v 18000 rpm motor from Jaycar. Matched it with a 12v gel battery and Quikrun esc. Pushed the limits but it went very well, though battery life was low. (Restored Sea Commander).

Eventually went back to a standard 550 brushed with a lith battery, still worked fine. I am about to take it off the shelf once again and hope to be out with it in a few weeks.

Hi Dgoss999, you're right, it's easy to find 24 volt esc too, I didn't think so.

Regarding the DC DC damper I think Dave meant to put it between the batteries and ESC. The DC lowering device placed there (if suitable also in terms of amperage) I imagine should not cause problems, even if it is not an efficient system.

Certainly using a suitable and suitable ESC directly (in terms of voltage and amperage) is the best solution (hoping they don't break immediately).
Thanks so much for sharing.

I would guess the 18v drill would have a motor inside that would be perfect?? The ESC would defined by the Motor, Brushed or Brushless..

Brushless ESCs run up to a higher max voltage but there are Brushed ESCs that support 24volt..

DC to DC devices at the current you would require would not be small or efficient and I'm not sure how a speed controller would handle them..

Remember also Lipos require a strict cut-off voltage else they will be damaged if you over discharge them. If you use a Lipo Drill Battery, this protection will be built into the battery and if/when the low voltage is reached, the vessel could just stop dead in the middle of the pond!!

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DG

Thanks Dave for helping me.

Well, I actually didn't understand anything.

What you say next is correct.
DC motors above 18 volts are found. The 24 volt ones are quite common but I don't think it will be easy to find a suitable ESC.
As you already said a DC DC step down circuit is the best solution.

Alessandro,

The way I understand his question to be, "can I use the batteries from my cordless tools to run my boat".
I believe he wants to use the batteries unaltered, so as to be able to swap from tools to boat and back.

The question that comes to my mind is an 18V battery is equivalent to a 5S Lipo. I am not aware of many or any boats that run on 18V (5S).

He will need to use a DC Voltage Buck Converter to bring the 18V down to whatever Voltage his boats needs.

Schmango, I like the way you think. I hope this information is useful.

Dave B

Hi Schmango, I don't quite understand your request.
You have some 18 volt drill batteries and you would like to use them. But what motor do they have to power?
Maybe you want a lower voltage?
If this is your requirement, consider that each battery pack is made up of multiple cells connected in series.
Each technology (Lead, NiMH, NiCD, Lipo, alkaline, etc. etc.) has base cells with its own voltage. Putting them together adds up these base voltages.
For example, primary (i.e., non-rechargeable) alkaline batteries have a nominal voltage of 1.5 volts. Secondary (i.e., rechargeable) NiCd (nickel-cadmium) and NiMH (nickel-metal hydride) batteries typically have an output of 1.25 volts per cell, lead-acid batteries have about 2 volts per cell.
If that was the question and you are handy, you can identify the type of battery, open the pack and put in series only the units you need to reach the right voltage.
It is not always possible to do this, but in many cases the battery packs hide other cells (often cylindrical in shape) electrically connected only with metal strips. Just unsolder the extra ones.

If the question is only about connectors then I think you can do it.

I hope I was helpful, but if I did not understand what you needed, sorry and just ignore this message.

Adapters for most of the major Tool ranges are available from Amazon. What you are asking about was pretty common practice back around 2002 when I first got back into flying model planes. That is around the time that electric flight really "took flight". The belt reduction system in many early cordless power tools was a real benefit to those who wanted to swing very large props. I don't use drill batteries myself I try to avoid LIPOs and prefer NIMH for safety.

Thirty plus years ago, I used to dismantle tired drill batteries and make them into packs to power my Deans Motor Gun Boat. Not as good as proper Nicad packs, but they were free!