Look what I found in the recycle bin

Batteries and Chargers Rechargeable Batteries
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I found another power pack in the recycle bin. In case no one has noticed, I have been posting the strange, rare finds to this thread. I would welcome anyone else also posting their unusual finds also.
Anyway, once again this pack looks brand new. However I suspect that it was to be installed inside of some piece of equipment. If that was the case, it could have been heavily used, but show no physical signs of wear and tear.
There it is. “36V/4.4Ah/158Wh”

There are warnings right on the label, first warning is “do not disassemble or open”

Warnings aside, I did press on, very carefully. This is dangerous stuff, should not be done by anyone not knowing what they are doing. (I don’t either. But I am really, really careful :slight_smile: )
So I took the first 2 layers of shrink wrap tubing off. The tubing was at right angles to each other. At this point I can see that this pack contains 20 - 18650 cells in a 10S2P configuration. Also at this point I am guessing that these cells will turn out to be of ICR type and not IMR. Two 18650’s in parallel would give the 4.4Ah capacity stated on the label if each cell was rated at 2200mAh. Already this pack is a little less interesting to me.

There is only a 2 wire socket that plugs this pack into the unit. All charging and discharging is done through those 2 wires. After removing the shrink wrap, a circuit board is now partially exposed. Also I can see that the cells are purple. I like the color!
There were 2 layers of paper tape also wrapped around the pack, each once again at right angles to each other. Here it is with 1 of the layers of paper tape removed.

Now we can fully see the heatsink for any power FET’s that may be in the circuit. Also we can now see the sense wires going to each of the cells.
Here it is after taking the second layer of paper tape off. After noticing the wimpy weld joints on the tabs, I am now pretty confident that this is not a high amp pack.


As I mentioned, the weld joints are pretty wimpy. Here are the welds of this pack on the right and the weld joints of a drill pack on the left. A drill pack, with type IMR cells, are built for much higher current loads.

Recently there was a group buy on the forum here for some Samsung 30Q’s As IMR’s are manufactured for high current loads, the come with flat tops on the postive side. The intention being that they will be welded into a pack. Some of the members here opted to have a third party install button tops. I hope those button tops were welded with the same kind of weld as a drill pack. Worse yet, I hope the button tops were not merely placed on top and held in place with another layer of shrink wrap.
I have seen that done with some rewraps of cheap UltraFires where the original cell was a flat top.

Anyway, I didn’t even think to measure the voltage of the pack. Voltage across all 10S2P is 36.0V!
To me that is a VERY, VERY good number! It is possible that this is a brand new pack, having never been used. 36.0V is just what I would expect to see if it was. Had it been any other number, it would have meant that this pack was used. And if it was used, it’s condition could range from very good to very bad. Before I tear this pack down any further I want to test the cells to see what condition they are in. I also want to see if this pack will balance charge with just an input charging voltage. Most drill pack chargers that I see connect to a drill pack battery with 3 or 4 or more connections. Even when the BMS circuit is in the pack.


36.0V divided by 10 cells in series equals 3.60V per cell, and that’s what each pair are!

Does anybody recognize what these cells are? I am thinking they are 2200mAh, ICR’s
EDIT: According to the label outside the pack these individual cells shoule be 2200mAh each, however dividing 7.2Wh by 3.6V as per the cell wrapper, we get 2000mAh cells.

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^

Thank you for another informative tear down dchomak. I don't recognize those purple ICR's.The SZNS makes them appear to be Chinese made, but that is a wild guess.

Pulled this one from an HD bin yesterday. Weird how it says 40V Max, but the cells should charge to 42 volts. Pack feels light for it's size because it has some empty space inside. No indicator lights came on. Opened it up. Build quality seems good. Had 10S1P Sanyo UR18650RX cells. Date codes were "T28", July 2015. So, pretty young. These cells are supposed to be good for 22amps continuous and have 2,000mAh capacity. Haven't tested any yet. They were at 3.26v - 3.27v. PDF

140

You and I have come across that “G Max” pack before. Me personally and you vicariously, thru me. :stuck_out_tongue:

Check out post 79 of this thread. (link only works with default BLF posts per page of 30)

Be careful with that one, a very wise person warned me :smiley:

“Damn, dcho. You brave (or maybe a bit crazy). This thing looks like a short challenge with an attitude”
.
.

Have fun, that pack yielded great cells for me.
a\also, save the connectors on the BMS board from that G Max pack. They mate with the connectors on the 18V Ridgid battery packs. Could come in handy if you want to use an 18V Ridgid to power some future project.
(Like maybe a combo Lantern - USB charger - MP3 player - Bluetooth Speaker - coffee maker) :partying_face:

141

that 36v is probably for a hoverboard.

142

specs
high drain type.score!

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Ha! Now I know why I had a moment of Déjà vu when I first saw the pack. Glad mine only had 10 cells because that 20 cell pack you got looks intimidating to me.

144

Good sleuthing!

All I could initially find was some info on the cells. Pretty much all I could find was, as ImA4 guessed, they were Chinese.
But your info invigorated me, and I thought to scan the QR code on the battery pack with my cell phone app.

And you were right, this pack is a high amp pack that came from a hoverboard!

A…much…more…interesting…pack. :slight_smile:
Now I WILL test the condition and report back.

Here is the site the QR code scan led me to.

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looks like it was designed to be safe.and not go nuclear if some kid gets it into a stall condition.
if those cells actually have the i.r shown they will be good for more demanding lights and tools.

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Yes, apart from the welds it looks like it is well built. That BMS board has 4 power FETs. It’s not made super cheaply.

I am in the process of charging it up and I will discharge it through 6 ohms of power resistors. I shall report how it does.
In the mean time, I have another pack that looked interesting. I don’t have great hopes on the cells inside, I’m just curious to know.

This one is from a Defibrillator! This one must have some really high quality, reliable cells.
Whatever they are.

The top was glued on and came right off, revealing a circuit board,

The circuit board resisted a little, but finally gave in to my persuasion.
WAIT, what the?

.
.
…
Sorry, couldn’t help myself. I thought of this the second I pulled this pack out of the bin and saw it went to a Defibrillator :smiley:
What it really contained was this,

Boring, and they were dead.

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Priceless my friend, priceless………… :smiley: …. . :+1:

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Interesting find you get three, 3v Lithium Sulfur batteries for a 12v item. I swapped out out defibrillator battery packs in some of our portable units. I found 4 D sized Lithium Sulfur batteries in each. Worthless for most uses as they use a wire from either end soldered to the board. Looks like a giant capacitor. So our department is using defibrillators using 4 D cells and theirs uses 3 CR2’s. That’s a huge capacity difference.

149

Just to keep it real, I thought I would post a couple of failures.
Today I found these 3 packs. 2 old discontinued Ryobi 24V packs and a new Echo 58V pack.

Turns out the Ryobi on the right had been through some sort of catastrophe and had melted parts inside. All cells were zero and there is evidence at the terminals of what happened on top of the pack.
The other Ryobi looks like it was used just a couple of times and it is on my charger waiting to be tested.

The 58V Echo is definitely brand new, never used.
ImA4 had already found one of the Echos, he said it looked new and it seems that the cells are in perfect condition, He found a 4A pack that contained 28 2A cells. I found the 2A version and it only had 14 cells. My pack looked brand new, but all cells were at zero. All I could do is strip the pack of its’ cells to get at the only thing left of use to me.
Cell holders!




And after a lot of work stripping everything out, I ended up with this. Enough to hold 56 cells!

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If you need a thing to store batteries in can’t you just drill some holes in a piece of wood?

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Sure you “could”…. but where’s the fun in that. LOL …. :stuck_out_tongue: … :slight_smile:

Plus, and this would be very unlikely; though not impossible: wood might contain just enough moisture to make the part of the battery contacting it do “funny things”. :wink:

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^
Agreed. Breaking down power tool packs is dangerous and fun enough to be addicting. Plus, there are usually nice quality components in them for folks that tinker with SMD electronics.

As dcho said, I was fortunate enough to get one of those packs with 28 like new cells. I can testify that the cell holders are very nice quality. Really holds the cells nicely with just the right amount of pressure. I liked mine so much that I ground off the tabs that stick out to the sides. They have been designated to hold my best high drain cells.

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When I first saw your idea I thought it was a good one. Actually if I was into woodworking I would probably have had done that already.

“When you’re handed a bunch of lemons, make lemonaide”

When I realized all of those cells were dead, that’s what I did. Also there is something poetic about using a cell holder for….
a cell holder. :slight_smile:

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BLF-noob here; will have to remember this. :smiley:

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I used to hit the neighborhood CVSes, Duane Reades, etc., anyplace that sold disposable cameras, and ask for those with flashes. When pressed, I’d say I was teaching a basic-electronics course, and wanted to give the students a circuit (the flash) that was pretty simple, yet interesting, to dissect.

Mostly worked. Some people (usually younger girls who couldn’t care less, as it wasn’t their property) would cheerfully fish out a dozen or two, load ’em up into shopping bags, and send me on my way. The younger guys would be all like, “Naw, you gotta talk to my manager, I don’t wanna get in trouble”. The managers would be the ones who would give me a hard time, saying the store gets “rebates” or somesuch, which I kinda doubted.

So there was more’n one reason to go when the teenyboppers were there. :smiley:

Nice, though. Flashtube, HV circuit, HV cap, and a lightly-used AA, in each one. Plus various gears, optics, etc., to play with. Don’t think I had to buy an AA cell in years…

And parallelled caps when charged up make a nifty spot-welder! Clear “whiskers” from worn NiCd cells. Etc.

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I forgot to report back on the condition of the purple celled “hoverboard” pack.
I charged the pack up and drained it into 2 - 3 ohm power resisters in series. After doing this I estimated that pack to have a capacity of “4108 mAh” or about the rated 4Ah. It could be that it is a brand new pack. Maybe thrown in the bin by someone who just didn’t want to risk using a hoverboard after seeing them in the news.
Apart from the wimpy weld joints, the pack seems to be well made. The included Chinese cells seem to perform well, how safe those individual cells are on there own is unknown.

Also of the last 3 packs I reported on here,

The pack on the left, a Ryobi 24V pack, charged up and is working perfrectly. It looks as though it is very lightly used and originally was rated at 2.6Ah. I tested it and estimate that this pack is good for 2.4Ah. My theory on this one is that the person that owned it threw it away because the tool it goes to broke. Ryobi has discontinued their 24V line, so that person had no other options other than ditch it.
I have a working 24V Ryobi weed wacker and can put this pack to good use :slight_smile:

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Holy cow, guys. I gotta learn how to scrounge for and correctly take apart these battery packs, because these are gold mines for 18650 cells!