Tutorial: Laptop Battery Pack 18650 Extraction

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Re: Thank You Members - 18650 Laptop Battery hack - WARNING - picture heavy

All can rest easy. The solder 'DRIP' mod to the three (3)18650s was a success. Completing the mod was more 'stress' than work. It took less than 5 minutes.

Take care,


Keith
 
QuePsi83 said:
All can rest easy. The solder 'DRIP' mod to the three (3)18650s was a success. Completing the mod was more 'stress' than work. It took less than 5 minutes.

Take care,


Keith
Click to expand...

Great to hear! Looks like I need to recycle some laptop batteries!


-Alex
 
Re: Thank You Members - 18650 Laptop Battery hack - WARNING - picture heavy

Have at it. I found my packs on the FleaBay. New replacements are a good investment. "Battery pack PULLS" are somewhat of a gamble. I've been fortunate on my first "PULL"... 5 out of 6 good cells.

Be safe,

Keith
 
Re: Thank You Members - 18650 Laptop Battery hack - WARNING - picture heavy

I just did my first "pull".
The funny thing is i dont have a light that runs 18650, yet.
 
Re: Thank You Members - 18650 Laptop Battery hack - WARNING - picture heavy

I take laptop packs apart from Ebay all the time for cells and have a pretty good rate of recovering good cells as well. Some types of casings can be quite hard to open up though and it is trial and error as to finding which models can be opened up easily. Some I have not opened up successfully at all because they are so tightly bonded together.

One thing I see in your picture is what looks like Al foil laying under your cells. Good idea from fire protection standpoint, but I would think that it would be very easy to create an accidental short and blow the internal poly fuse. One thing I use for cell disassembly are those 12" by 12" or 18" by 18" ceramic floor tiles that Home Depot and Lowe's sells. No risk of shorting out cells and fire proof as well.

I also do a complete charge-discharge cycle on every working cell to find it's capacity and compare it to manufacture's specs. I generally grade to 3 grades: 1. Like new (>95% nameplate capacity) 2. Usable (80-95% of nameplate capacity) 3. Recycle (<80% of nameplate capacity). My experience is that about 40% of cells fall into the 3rd grade when buying used packs off of Ebay. Not saying that you won't find good cells though, as I do have a few hundred like new cells from taking packs apart, just that not every pack you open will produce good useful cells. I generally only go after Ebay auctions that are selling 10+ packs per lot at $3 per pack and no more. You can find them if you are patient and sometimes very large numbers of packs at times (I got ahold of 60 Macbook packs one time that I turned into a large reserve battery for camping/hiking). I have plenty of cells at the moment and haven't bought any more the past year, so not sure if pricing has changed much since then. Including all the bad cells from the packs, I'd say that I dollar cost averaged at about $1.00 per good cell that I have.
 
Re: Thank You Members - 18650 Laptop Battery hack - WARNING - picture heavy

My only source of laptop batteries for recycling has been at work, and they are always highly abused giving very disappointing results. Out of the last three packs I've got about 5 usable cells.

As far as pack disassembly one point I would make is that using tools can be risky. In fact these last few I opened entirely by hand and only once I had the cells completely out did I use tools to separate the individual cells.

To be honest though, as satisfying as it is to recover the cells I don't really trust them that much and think it is worth buying new ones so you know exactly where you stand.
 
Recovering batteries from notebook battery pack

Hi!
I have a 1 year old dell batttery pack. It has 6 18650 cells.
I will check their voltage with a multimeter later.
If they are still at 3.6v, it is safe to charge them? (i have a nitecore i4 v2 charger)
If they are lower (under 3.6v)... is there anything i can do?
I know that if they are near 1.5-2v, it's their EOL.
Thanks!
 
Re: Recovering batteries from notebook battery pack

I recovered the cells!!
They were all at 3.6v at time of extraction.
The old zinc bathtube is where i am ready to throw the cells in case of fire/heat/shortcircuit/etc, and then pour sand over them.
I'm charging them now. By the configuration they seem to be 2200mAh cells.
Could they be sanyo ones? They have written: A ND9A37 085761

High res Album for the interested:
http://imgur.com/a/8c1w3#0
 
Re: Recovering batteries from notebook battery pack

Hi ltcdata,

You have extracted sanyo ur18650a, it appears. There is some debate as to whether these are 2250mAh (4.2V) cells or 2800mAh (4.35V) cells, though apparently the 2800mAh ones should have an orange wrapper?

quoted from various internet sources. Older sanyos were that reddish pink color that the cells you extracted are.
Older cells:


Sanyo UR18650F 2200mAh red ring


Sanyo UR18650A 2250mAh violet ring


Sanyo UR18650F 2400mAh green ring


Sanyo UR18650F 2600mAh teal blue ring


New 4.35V cells:


Sanyo UR18650ZT 2800mAh violet (orange cell cover) 4.35V


Sanyo UR18650ZTA 3000mAh yellow (violet cell cover) 4.35V
Click to expand...

http://i832.photobucket.com/albums/zz245/electronman5/Sanyo.png
Click to expand...
^from that:
Note:
1. Stamp lot number on the tube
xyyz
x - year (`96=A, `97=B, ..., `10=O, `11=P, ...)
yy - week (01, 02, ..., 48, 49, ... 53)
z - Changed Career (A, B, C, ....., Z)
2. Stamp 'SANYO' & 'R1112' of cell model on the tube

Doesn't seem to be 100%, don't know how to use that to decode your lot no.s.



Some more tips to help you identify: convert the battery pack's Wh rating to Amp Hours by dividing the Wh rating by the nominal voltage listed on the pack. Now, you have the entire pack's Ah rating @ the pack's nominal voltage.

Laptop battery packs are generally two parallel strings to double the capacity, so you can divide the pack's Ah rating to get a string's Ah rating @ that series string's nominal voltage (which would be the same as the pack's nominal voltage)

Three cells in series is generally the perfect voltage for laptops, this is where they get the nominal voltage. So, you can divide the nominal voltage of the pack by 3 to get an individual cell's nominal voltage.

You now should have the info you need: a single cell's nominal voltage, and it's Ah rating.
 
I went on to disassemble two 6 cell and one 9 cell battery pack.
The result is five bad batteries (measuring less than 1.2V) and sixteen good batteries (two measuring 2.99V, the rest 3.3-3.6V).
Pink ones are made by Samsung and green ones are Panasonic.


SAMSUNG ICR18650-26D


SAMSUNG ICR18650-26C


Panasonic CGR18650A


http://s20.postimage.org/46wlt0wsd/IMAG0412.jpg


When I removed contacts some have bottoms very slightly deformed during the process of removing contacts. I hope these can be seen from this picture. Will this cause any trouble in operation?


http://s20.postimage.org/cdolklmv1/IMAG0416.jpg
 
I've just ripped out a IBM T43 battery that was unchangeable when inserted in the notebook. The batteries model is CGR18650D and look like the following:

pa.cgr18650d-ab.jpg


I measured the voltage using a multi-meter and got the following results:


  • 2 measured ~0.65V
  • 2 measuured ~0.1V
  • 2 measured -0V

I do not have a 18650 charger. I've already bought a 18650 USB charger box as below and plan to use these batteries.

Any advise can I still use them?

 
Probably not.

The first two may be able to be restored, but it isn't likely they will have much life left in them. The other 4 are likely goners.
 
I was issued an IBM Thinkpad at a place of work 9 years ago, and didn't realize I still had a laptop battery for it. It was one that wasn't delivering enough juice and I'd gotten a replacement. Somehow I never threw out the old one. Today I extracted the batteries, which turned out to be Panasonic CGR18650A cells. Four tested below 1.0v, and two tested at 1.43v. I'm tempted to give the 1.43v cells a try, to see if there's any chance of revival.... although I expect they're really too old to have much of a capacity any longer.

EDIT: OK, I read up some more... and 18650 cells that are 10 years old should be avoided. I'm lucky I didn't go the distance and try fully charging these cells (I just did a partial charge test). They were able to rise back above 3v, but they got quite warm... which has been cited as a potentially dangerous problem. Not worth the risk.
 
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I have a more recent laptop battery that wouldn't charge any longer. I pulled the batteries from it (MAJOR pain--no weak seams anywhere), which showed to be lavender shrouded Samsung ICR18650 cells. 3.85v, 3.85v, 4.0v, 0.25v, 0.23v, 0.19v. So half of them are usable. Not bad. Certainly don't need to buy any unprotected 18650's for a bit. 😉
 
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Wow thanks for this info. I have a XP knackered Asus Eee tablet and manages to salvage 4 x 18650 batteries from it. They are yellow in colour so I am not sure of the maker, but they have charged up great and will be of great use in my LED torch in the future. Thanks again.
 
Need some direction, and I am probably excessively cautious, but I have grown fond of my eyes, limbs and body as I approach my half a century mark 🙂

What I have is a small pile of laptop battery packs. And a virtual endless source. Yee-haw.

So far, only by the grace of God, I have managed to dissemble two packs, one from a Dell and one from a Toshiba. Without significant incident, so far.(One spark while I was cutting the tabs off)

Being excited as a little kid, I didn't log what cells came from what (which I won't do again) but I think the Dell, my first harvest, was the one with the dark green cells.(Sony?)
No problems opening up the pack,easy and the tabs were long enough for me to cut them without a spark.
Yipee, 6 of 'em, all measuring 3.69v each.

So, next,I think was the Toshiba, same easy clearance, but as I was snipping the tabs I got ZZZZZZAP which woke my arse up real bright like.
The good thing was that out of 8 red (I think Sanyo 2400mAh) cells I got 6 measuring 3.78v. 2 were so low I taped both ends of each and set them in the discard area.

So, today, several days later, I proceeded to pop open another Dell.Different external pack, gray.
And, to my delight, I spy 6 BEAUTIFUL teal CGR18650D cells! Panasonics!!!
Jackpot baby!

But I stopped. These things are in tight, very tight, with a pronounced hardwired protection circuit.
In this config ++spacer--spacer++PCB


{EDIT}

Not as promising, 3.1 was highest voltage pair, probably set these aside until later, and read some more

{end-EDIT}

Now in all these tutorials I have yet to see demonstrated which tab to cut first. So not wanting to blow up anything, (or me) I am just wondering if there is a sequence to these things cut wise.

Do you just go through and cut every positive pair? Or does it matter?
PCB cut first? Or does it matter?

Sequence is of what I inquire, just trying to be extra safe about this.
Thanks 🙂
 
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Hello Gr8Scott,

Welcome to CPF.

The main point is to be careful while cutting. The actual sequence is not important.

I tend to cut the packs into pairs of cells, then separate the pairs as needed.

Tom
 
SilverFox said:
Hello Gr8Scott,

Welcome to CPF.

The main point is to be careful while cutting. The actual sequence is not important.

I tend to cut the packs into pairs of cells, then separate the pairs as needed.

Tom
Click to expand...

I do the same, I use side cutters that snip through like butter.
 
I'm in the I.T game and I look out for laptop batteries that still work, so I know the history of the pack , oddly enough on most 6 cell packs it always 2 cells that are below Voltage , some of these I'm busy recovering to test their discharge rate, and to find out why it's always 2 cells (have this theory that they are designed to fail).
 
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