Some harvesting surprises

neilmc

neilmc

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May 22, 2017
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I've only just started harvesting 18650s from some old laptop batteries I've had laying about + recieved 3 from eBay today.

The batteries I already had were from 2011 and have had plenty of cycles ( and some bad cells showing up). I'm not expecting much from them, but a couple of surprises. Some cells at 0.1v or under I didn't bother to charge. Some at around 1v surprised me that they still yielded about 1600mAh (but I'lll probably use them for torches or something).

The 3 Toshiba packs that arrived today initially left me disappointed.I paid too much for an unknown really. $54 for max of 18 cells if all are good.

Opened the box ..... happy... looked like unused stock in original Toshiba boxes. Then sad when opening them to find panasonic cells with amanufacture date of April 2010 and all cells at around 1.5v. So 7 year old cells sitting at under 2v for who knows how long.

My pessimism might have been a bit hasty though. First discharge of the first two cells have yielded 2405 and 2408mAh
 
Nice haul! :) Those kinds of surprised are always welcome! It's fine to have cells at a low voltage, if they self-discharged themselves that low.

It's better if a cell self-discharges .01 volt a month or so for 5 yrs (loosing approximately 2.6V; if disconnected near full charge), than for a cell to be used down to 1 volt. The cell can recover a lot easier from a self-discharge than from a deliberate discharge. Just the way the chemistry is.

So, you probably will get a lot outta those cells, even for being 6-7 yrs old. :)
 
Agree fully with Korishan. I've been going through a lot of new old-stock packs myself. Most of them come out of the packs at 1.0-2.0v because they sat for so many years. 99% of them charge perfectly fine and are well within spec for capacity. The remaining 1% look like they leaked. I obviously didn't try to charge those. Out of the ones I did charge, probably close to 750 cells now, not one single cell has shown capacity out of spec.
 
NOS is like the holy grail, I've transitioned to only getting NOS panasonics, you pay a bit more outright, but considering defect rate is almost non-existent it's more than worth it. Some of my highest capacity cells were at 1v out of the pack, any heat during the first cycle was gone in subsequent cycles
 
Now I think of it, I haven't had one bad Pana in the hundreds I've tested. They're the ducks nuts :cool:
 
Scepterr said:
NOS is like the holy grail, I've transitioned to only getting NOS panasonics, you pay a bit more outright, but considering defect rate is almost non-existent it's more than worth it. Some of my highest capacity cells were at 1v out of the pack, any heat during the first cycle was gone in subsequent cycles
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I might be heading for no bad cells in this lot of 7yr old panasonics. Ten cycled so far and none below 2400mah.
 
I got a couple cases of VZSU51W 8yr old NOS, NCR18650 grey with matrix dot top, original cell capacity was 3000mah, every single one tested over 2900 on the first cycle
 
I was considering buying some cheaper 2000-2200mah cells in bulk to speed things up a bit, but I'm now leaning back towards brand name reclaimed cells.

I pulled some cells out of an aftermarket laptop replacement battery. OK from new, but only 1800mah. I did a test purchase of a NoS replacement battery (seller seems to have plenty) and while they were marked 1800mah, tested to only 1100-1200mah. No idea how old they are.

Some of my old ideas on the longevity of 18650s has changed. I found an old Dell laptop in a storeroom at the office. I know it well. I bought it when the business opened 11 years ago. It was used for 5 years and then sat in storage for 6 years. Battery life was always horrible on it even from new (about 1.5-2 hours). I wasn't expecting anything from the cells in it.

I've been pleasantly surprised. 9x purple Panasonic CGR18650E. The first 3 have tested at 2000-2100mah :)

In contrast, my mum asked me about a battery warning on her 5 year old Dell laptop. I had a look and the battery pack was red hot (so I guess laptop BMS aren't always great at keeping packs safe). I opened the pack. Red Sanyo cells. Every single one of them got to 80 deg C within 20 min charging at 500mah.
 
1st Wow: nice find on the "old" laptop cells. You'll probably find that 1 cell may have been bad and brought the rest down

2nd Wow: yep, the laptop bms' can be cow hockey at times. There were a few laptops that were recalled due to defective power bricks or batteries or what not. Your moms could have been one of those. On the other hand, maybe the bms was working semi-fine and it didn't have a functional temp probe or where the probe was it wasn't reading hot enough.
Hopefully mom got a new battery ;)
 
Neilmc, that's typical of generic packs, besides the cells never being right capacity to match what the battery pack says, you'll never find a spec sheet on them.
I think the best deal right now for brand name cells is the eBay hoverboard pack auction, LG and Samsung 2100-2200 10A draw cells for $1.10-1.25 each depending on quantity. Not 1 bad cell in the 600 LG cells I've gotten and all tested near original capacity. Sooo much time saved on disassembly and virtually no risk of destroying cells. Also save time on initial charge if you charge the whole pack before disassembly
 
Scepterr said:
Neilmc, that's typical of generic packs, besides the cells never being right capacity to match what the battery pack says, you'll never find a spec sheet on them.
I think the best deal right now for brand name cells is the eBay hoverboard pack auction, LG and Samsung 2100-2200 10A draw cells for $1.10-1.25 each depending on quantity. Not 1 bad cell in the 600 LG cells I've gotten and all tested near original capacity. Sooo much time saved on disassembly and virtually no risk of destroying cells. Also save time on initial charge if you charge the whole pack before disassembly
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I'd jump on those hoverboard packs, except I'm in Australia. I'll keep hunting around. A local PC repairer is happy to give me any batteries they come across, but they don't get many. I'll ask around some more.

Korishan said:
1st Wow: nice find on the "old" laptop cells. You'll probably find that 1 cell may have been bad and brought the rest down

2nd Wow: yep, the laptop bms' can be cow hockey at times. There were a few laptops that were recalled due to defective power bricks or batteries or what not. Your moms could have been one of those. On the other hand, maybe the bms was working semi-fine and it didn't have a functional temp probe or where the probe was it wasn't reading hot enough.
Hopefully mom got a new battery ;)
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She said that she never used it away from power, and it boots without any errors with the pack pulled, so she's just happy that the battery warning is gone :)
 
I would ask the seller if he's willing to ship to AU, I would say its still worth it up to $2/cell shipped. The amount of time saved just getting the amount of cells you need for whatever size wall is tremendous. Took me months to get my first 7S80P collected and tested, one order and 2 weeks of testing and I have my 2nd 7S80P with LG cells ready
 
If you have to buy the cells then it is not worth it, I think that we are doing that for fun and recovering the good cells that go to the bin, if you have to buy them I will prefer to buy lifepo batteries, a cell with 2000 mAh at 2 $ is 1 $ / Ah almost like lifepo and with these you do not have to make any work soldering and life of lifepo is usually 4 times the life of li-ion.

So if I had to buy I will buy lifepo.

Regards
 
Even if she's using it w/o the battery, it's not healthy for the laptop to run this way. It uses the battery as a "buffer" when connected to the wall. It helps to regulate the power a bit.
But, more importantly, if the power flickers at all, it could have adverse effects to the laptop and potentially dataloss could happen to failure of the laptop totally.
I worked in IT at the local college and we had a few laptops die because the battery wasn't installed even though it was plugged into the power brick.

Just a friendly fyi :)
 
Korishan said:
Even if she's using it w/o the battery, it's not healthy for the laptop to run this way. It uses the battery as a "buffer" when connected to the wall. It helps to regulate the power a bit.
But, more importantly, if the power flickers at all, it could have adverse effects to the laptop and potentially dataloss could happen to failure of the laptop totally.
I worked in IT at the local college and we had a few laptops die because the battery wasn't installed even though it was plugged into the power brick.

Just a friendly fyi :)
Click to expand...

Thanks :)

She's going to replace it soonish and power is pretty stable where she is. Photos etc are backed up and it's mostly used as a web/email machine.
 
Wow, Panasonic make some robust cells.

I sat some cells aside a while ago. I almost threw them out because of what they looked like (Purple panasonic):

image_tftwkn.jpg


They're from abattery I got from the local tip. There's a recycling shop there that sells me laptopbatteries for $2 each. This one had clearly been sitting in dirty water for some time. The BMS inside the pack was all corroded and there were water marks through the pack.

All of the cells showed discolouration under the wrappers and they were only 1.2v. It looks like some electrolysis occurred inside the pack based on the dirty grey deposits on the cell casing.

I cycled them recently and they all tested to around 2200mah! (and stay cool during charging and discharging)

The crud on the metal casing cleans off easily with steel wool, and re-wrapped they look like new. I'm really glad I didn't throw them out :)
 
I still wouldn't use them personally.
Some water may have got inside the positive end.
I have thrown away hundreds of power tool cells after opening packs that have obviously been left out in rain or submerged. Most still test fine. Just not worth the risk of future failure imo
 
Wattsup said:
I still wouldn't use them personally.
Some water may have got inside the positive end.
I have thrown away hundreds of power tool cells after opening packs that have obviously been left out in rain or submerged. Most still test fine. Just not worth the risk of future failure imo
Click to expand...

Good point. I might leave them out of larger packs. I might put them in my "torches n stuff" pile :) It's only 6 cells anyway.
 
Yeah, I agree with Wattsup. It's possible the CID maybe damaged as well. So in a pack would be an iffy thing. Definitely hazardous for something that's plugged into 1000's of amps capable.
Flashlights are good ideas :) Now that's a bright idea :p
 
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