Power Tool batteries safer than from battery builders?

Hi all,
After reading about fires from DIY (and cheap commercial) electric vehicles while charging I am getting hesitant about building a board.
If I had a house with a garden I would charge it in a tiny shed, but I live in an apartment block and don’t want to risk the property and lives of my family and others.
I haven’t seen much about using power tool batteries here which I am surprised about. From reputable brands, they should have been quality tested properly.
I also like the fact that you can have some spare ones in a backpack.
Any downside to using that kind of battery?
If the verdict is that they are not good, can anyone recommend a high-quality battery builder in Europe (not UK)?

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They will technically be safer because the bms in these things is not bypassed.

But the current draw will be very limited, depends on how many of these packs you will use in parallel.

I don’t recommend going down this road

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Check out the battery builders club

I was going to make a thread on this forum about power tool batteries. Not necessarily for using them in PEV, just for discussing the different tech that they use and for getting 3D printed mounts designed for the common tool batteries.

I think they are perfect for powering stuff like lights when you don’t want to use a DC DC, and lots of other little electronics projects.

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It’s annoyingly not obvious, but some tool brands do not use a BMS inside the tool battery. The BMS and some of them is actually inside the tool and therefore if you use the battery for something else you can drain it to 0 volts. Vesc solves this sorta but gotta take packs off to balance then.

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I don’t think that is legal in EU, but not sure.

Good to know though.
For electronics projects I would also like to see some 3d print mounts. Good idea :+1:

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My favorite tool battery for diy is the one that comes with the $15 harbor freight drill.
3S1P crap 2.2Ah cells but you really can’t beat $15 and it comes with a motor, gearbox, switch and 15V (I’m confused too) charger.

If you buy the $20 kit that includes the god-awful flashlight you get two of the mount adapter clips.
Almost sort of derailing this thread I’ll start the other thread and post the cad files and stuff.

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This is on topic imo

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Yeah but the harbor freight battery definitely shouldn’t be used to power most esk8 although for a kid’s board probably not a bad idea.

Would be great with a thread like that!
I assume you have seen these 3D Print Files:

My next esk8 will use an Ego Powerplus battery :slight_smile:
They are generally safer for charging but more dangerous to ride since their brake current is pretty low and their bms can just cut off

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@Andy87 get in here it’s 7 + 8 + 9 Andy Party Time

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best practice that foot brake and slowing early.

Not much I can say to this topic, but just for the good will having another Andy in here…
It’s good to see that people actually think about the dangers of having an esk8 in a multi family house before they buy one. Especially with those batteries getting bigger and bigger in modern boards. Esk8 owner always should have a plan A, B and C if things go wrong. If OP does have a balcony, probably best option would be a metal box placed there for charging and storing. Something that can contain the flames and don’t give the fire to spread.

About power tool packs used in esk8, I never considered this as an option for me. I have seen people using those before more or less successful. It all depends on what you expect from the board you are building.
The packs do definitely don’t have the greatest form factor. So more space needed for less range. Different aging of cells in the individual packs might cause issues over time. Also connecting different voltage packs because of not even charged packs might cause problems. I don’t know enough about the bms inside of power tool packs, but I could imagine that those could cause some troubles along the way as well.
My personal conclusions would be to better get an „external“ pack (like pelican box) made by one of our battery builders. The battery box can than always be taken off the board and stored/charged in a save place.

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Sounds more like an EUC pack. Stay safe everyone. :metal:

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Have been thinking about this for a while. What’s your plan?

While I’ve never used these in an Esk8, I do run two of these in series in a cordless rotary hammer drill, so I’d say they’re durable enough for an esk8. They’re expensive, but you’d probably only need 2. Based of off the specs I’d guess that what you’d find inside is a 10s2p of Samsung 40T, that’s pure speculation but it makes sense to me.

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Excuse my incompetence - what is an EUC pack?

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an EUC battery

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So I am not building a typical esk8.
I am building a three wheeled mountainboard. I am using a single wheel at the real with a hub drive motor, a flipsky ESC and a 10Ah ego power plus battery with the “hip holster” to mount it. I will also buy a 12Ah battery to swap.
I considered using two or more dewalt batteries, but I think that using a single, large battery works better than two separate ones, for the reasons Andy explained above.
Personally I think the worse form factor is offset by the possibility of carrying and swapping spares.