Dewalt Flexvolt 60V / 20V - 12AH

Hi –

Just starting my e-foil build and I happened to come into possession of five sets of new 12AH DeWalt FlexVolt 60V / 20V batteries. I’d rather not tear them apart for the cells and leave them as mostly stock, in their cases. I found ways to 3D print a cleat for attachment, which would be convenient. It seems like the available current draw needs to be understood. Any advice on design of a setup? How many should I use for a brushless setup? I read through this previous post. Any help is appreciated.

That is 1.2kwh worth of battery, so it should be enough energy for some decent ride time. Open one of them up to see what cells they are using so we can tell you how good or bad of an idea this might be to wire them up for the loads an efoil produces… it looks promising and should be okay.

If you don’t want to tear them all apart. (Believe, me I know how much work it is. I once dismantled dozens of makita packs to harvest the sony konion cells inside.) . The best approach would be to run all of them at 60v in parallel.

They should be 16s or 67.2v hot off the charger which should be just low enough to keep you from frying your balls off in the water if they should be okay the 75v VESC’s like trampa, flipsky, makerx. I guess if you fry an ESC you will know to either step up to a 100v VESC or dismantle the packs and reconfigure to build a slightly lower pack voltage however the math works out best with the number of cells you have.

at 60V these have “only” 4Ah!
12Ah is availible only on 20V output. This is 5s battery inside, 3 rows. Means they could be run as 5s3p or 15s1p.
If you do not need them for powertools, you should disassemble them. There is way too much electronics and magnetic switches inside these batteries.

See my thread here:

A few posts down you will see how I used my 6Ah batts. They work well.
The Flexvolt batteries are very thick so that might be an issue. I don’t have any Flexvolt tools. How do you select the voltage?

Also, please post if you find spade connectors that fit in the plastic top piece and still are long enough to get a solid fit. I had to use make my own using .22 Mag shell casings. Also, consider using these at 40V. 60V’s would give you a lot of top end but at a slower cruise speed you will be running what I consider to be a very inefficient low RPM.

I think @HighAltitude gave me enough info not to tear them apart - will verify by looking for a teardown on YouTube. Very helpful on the VESC info - will let you know how it nets out. Thank you.

@HighAltitude, I work in construction tech, so I have a funny motivation to keep them together. I’ll let you know it goes with connections. Switching is done without a physical switch - I’ll figure out what my voltage options are and how to enable them.

This might give you answers.

Summary of the teardown video posted by @Toto44:

  1. The DeWalt 60V / 20V has a mechanical switch, triggered by the cleat on different tools.
  2. Pulling 60V (without tearing it apart) would require some trickery. At 60V, it senses the tool differently and won’t give you more than 20V.
  3. The winters appear to be cold in Canada.
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Can you explain#2? “At 60v it won’t give you more than 20v?”

Seems like it only needs a simple bridge according to this guy ( at 4:20. He gets 60V with an adapter like that

Where are those long spade connectors from? They would be perfect for my build.

This type needs the mechanical actuation on the switch inside the battery ( which controls an electronic/solid state switch inside ) but also the external jumper to get the 60V out. They went trough a lot of effort electronically and mechanically to make the battery as universal as it is whilst also be compatible to a very big family of tools.

So unfortunately its a combination of two actions :sweat_smile:.