Is this a bad idea?

I’ve got these Ryobi batteries super cheap. They are Samsung 20Q 2000 mAh 15A cells which is kind of a bummer.

Datasheet

So here are some pictures of the cells in their current layout.

This is my plan for the final layout for putting two in parallel to have a 8Ah pack.

why is it a bummer?

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I don’t think you can reach 36v/8ah with just 20 of these(as far as I can tell). You’d need a 10s4p. This puts 4 of these in parallel to get 4x 2000mah = 8ah.

Or do you happen to have 2 of these packs which adds up to 40 cells ?

::// and 15A is not bad at all. It’ll add up to 60A continuous.

Sorry I forgot to mention that I got two packs.

@barajabali I thought these batteries would have a higher discharge rate than that. Still great cells.

I guess, why not :slight_smile: Go for it. Check voltage and balance beforehand.

Just noticed these can be grabbed for 25$ 18v pack… Not that bad of an deal. And 20Q should definitely be usable in eSkate.

This is the 40V version. Ryobi Model number OP4040 in case you wanted to check em out.

Basically just two 18V 4Ah packs in series.

15 amps per cell is actually pretty good!

Indeed. Only a little behind the Samsung 25R’s that we frequently use, so a few in parallel should be fantastic!

Sorry to dig this up. Winter is here and I have an itch :slight_smile: I have a bunch of Ryobi batteries that seem to have defective bms’s. The pack and parallel group voltages look promising. I have one more of these p108’s and two smaller packs to take apart still. Did you go through with it? Did they perform ok?

Not sure of the smaller packs use 20q’s too but if they do I have about 60 cells and would hope really for an 10s4p or maybe 5p if the cells check out.

Thanks for any feedback.

I would try to get a data sheet on those exact cells. Are you planning on leaving the cells in there current welded configs? If so it might be hard to integrate a BMS. Taking the welds apart is so time consuming as well so be sure a 10s4/5p pack would be sufficient for the high max current you need…

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The 13P and 20P get horribly hot at 2-3A loads At least the 200 or so I’ve harvested

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I’ll take a look for a data sheet. I’m going to start charging the parallel pairs and see how that goes with my Hyperion duo. Hoping to leave them in their bulky bricks and just run them as 2 x 5s 4p packs for charging. I think I can actually stuff four of them into my psychotiller flagship enclosure with one vesc-x.

edit I found the spec sheet for them here http://lygte-info.dk/review/batteries2012/Samsung%20INR18650-20Q%202000mAh%20(green)%20UK.html

Hey. I saw this was old, but I was curious because I have these cells, but the boards in the batteries died. Were you able to use these? If so, How did you do it?

Diggin up a super old thread…

Is your question about Cell recycling in general?

My personal opinion when it comes to esk8 battery for an esk8 you wish to ride reliably on a regular basis is to Invest in a quality pack.

Cheap hack together batteries projects can be dangerous for two reasons. Imagine your house burnt down and you loose all your sentimental belongings due to saving a couple buckz. Imagine it fails on you at you get stranded somewhere, or worse it casued a crash.

On the other hand, if you are primarily interested in learning about battery building and mostly want a project for educational purposes its worthwhile and can be fun.

Also note, if you dont already have all the tools you need it could turn out to be far from a cost effective battery build, however knowledge is priceless.

I do intend to use them, but it is mostly because i am interested in learning, i could easily buy a battery pack, and in fact have. but to have another would be cool too. I took the ryobi batteries apart, and checked the cells, they are fine, where as the circuit board bs had a blown capacitor. i dropped it off my roof. So i might as well use these good cells. as for the fire. I am a firefighter, totally immune. just kidding, good insurance, easier to move when your house burns down. Anyways, I have the tools, did you just dismantle it, and weld on new nickel strips?

Experiment away sir!

lol[quote=“onloop, post:17, topic:18245, full:true”]

lol