Average Salvage Success Rate 18650

cstanley

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Jan 2, 2017
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What has been your guys average success rate when harvesting cellsfrom old laptop batteries? So far, I have got 10/41 cells (25% success rate) out of 7 battery packs so far. I have 43 more laptop batteries to go, so maybe my success rate will go up. This seller on ebay posts lots of them, however some are generic so I'm not sure if I will continue buying from him.

I have been setting aside batteries that have a lower than 3v, some of them have less than that. I haven't tested anything else yet (capacity, resistance etc) - what are your other limits?
 
From my report on what I have found on my thread http://secondlifestorage.com/t-Project-Daft-Idea
, further data will become available as we have been through charging/dischargin:


Some statistics based upon a voltage check only, out of a total of 173 Cells coming from a sample of 29 battery packs.

126 Cells > 3.5V
28 Cells > 2.0V but less than 3.5V
10 Rows > 1V
9 Rows less than 1V.

Out of the 173 Cells, 2 are scrap due to physical damage, Both are LR1865SE from different battery packs, and a further is failed due to falling rate voltage as mentioned above.
 
If you know where to look, you can have a very good success rate.

I recently went to a scrapyard and picked up 104lbs of laptop computer batteries. 50lbs of those batteries were all the exact type of laptop battery. It turns out a public school had stopped at the scrapyard and dumped off over 50lbs of laptop batteries there along with some other computer equipment, only for me to pick up the batteries later. My guess is those laptops spent their days being plugged into the wall, thus they were never used. Of those 50lbs of laptop batteries from this school, I have had an over 70% success rate. But let's break this down further:

10% were DOA (0v, rusty cells)
10% tested to have >1000mah and were rejected
10% were tested to have a capacity of around 1500-1900mah
70% were all tested to be good cells above 2000mah.

When I was tearing apart these laptop batteries they were all the exact same levono battery. But it looks like levono had gone shopping, as I had found several different brands of batteries with the same capacity inside each laptop battery including but not limited to:

LG BB4 2600mah
LG BB3 2600mah
Sanyo UR18650FM
Samsung ICR 18650 26D
Panasonic CGR18650E

The Samsung cells I have had very good success rate, most are testing to be over 2500mah, so practically new. The panasonic cells come in second. Their cells have tested every single time to be above 2000mah per cell, with none going below that. The sanyo cells come in third. Most of those cells are tested to be around 2200mah, although there are a few outliers that are only doing 1500-1700mah per cell. The LG BB3 and LG BB4 cellls are performing all over the place. One day I get cells that are above 2400mah, other days the cells are under 1700mah, although the majority seem to be around the 2000mah mark.

I guess it just goes to show you that at least in the late 2000s, samsung built the longest lasting 18650s, with everyone following.


cstanley said:
What has been your guys average success rate when harvesting cellsfrom old laptop batteries? So far, I have got 10/41 cells (25% success rate) out of 7 battery packs so far. I have 43 more laptop batteries to go, so maybe my success rate will go up. This seller on ebay posts lots of them, however some are generic so I'm not sure if I will continue buying from him.

I have been setting aside batteries that have a lower than 3v, some of them have less than that. I haven't tested anything else yet (capacity, resistance etc) - what are your other limits?

Also, if you want the best deals possible, skip ebay. Go to your local scrapyard. I was able to purchase laptop battteries for $1.25 PER POUND. not per battery, PER POUND. Even after fully testing all the cells it means I paid only about 30 cents per cell. You are never going to find a price that good on ebay.
 
cstanley said:
This seller on ebay posts lots of them, however some are generic so I'm not sure if I will continue buying from him.

What was the sellers eBay name ?

It would be interesting to compare the quality of cells salvaged from the numerous sellers who all appear to have access to very large sources- I also see many selling obviously old packs.

Coincidentally, yesterday I purchased a batch of 20 from eBay for the first time for a couple of UK pounds per pack - I don't really need any more cells but I'd like to do a proper break down of end cost per usable mAh - or some other useful data.
 
I collected a bunch of data on the correlation between initial voltage and tested capacity - the upshot was there's isn't much - so I'd recommend capacity testing anything you find over 1 volt.

From my sample (from a New Zealand IT recycler) I was getting about 75% usable - depending on how low you are willing to go.


Cheers, Paul
 
The same for me, capacity is not really related to initial voltage, some 0v cells are >2500mAh and some 3.5+ are toasted and <1000mAh.
Success rate depend on the source, from some computer shop I got series of battery with a rate around 90%, from other it drop under 50%, very old batteries (less than 2200mah cells) are mostly crap.
 
CUDAcores89 said:
If you know where to look, you can have a very good success rate.

I recently went to a scrapyard and picked up 104lbs of laptop computer batteries. 50lbs of those batteries were all the exact type of laptop battery. It turns out a public school had stopped at the scrapyard and dumped off over 50lbs of laptop batteries there along with some other computer equipment, only for me to pick up the batteries later. My guess is those laptops spent their days being plugged into the wall, thus they were never used. Of those 50lbs of laptop batteries from this school, I have had an over 70% success rate. But let's break this down further:

10% were DOA (0v, rusty cells)
10% tested to have >1000mah and were rejected
10% were tested to have a capacity of around 1500-1900mah
70% were all tested to be good cells above 2000mah.

When I was tearing apart these laptop batteries they were all the exact same levono battery. But it looks like levono had gone shopping, as I had found several different brands of batteries with the same capacity inside each laptop battery including but not limited to:

LG BB4 2600mah
LG BB3 2600mah
Sanyo UR18650FM
Samsung ICR 18650 26D
Panasonic CGR18650E

The Samsung cells I have had very good success rate, most are testing to be over 2500mah, so practically new. The panasonic cells come in second. Their cells have tested every single time to be above 2000mah per cell, with none going below that. The sanyo cells come in third. Most of those cells are tested to be around 2200mah, although there are a few outliers that are only doing 1500-1700mah per cell. The LG BB3 and LG BB4 cellls are performing all over the place. One day I get cells that are above 2400mah, other days the cells are under 1700mah, although the majority seem to be around the 2000mah mark.

I guess it just goes to show you that at least in the late 2000s, samsung built the longest lasting 18650s, with everyone following.


cstanley said:
What has been your guys average success rate when harvesting cellsfrom old laptop batteries? So far, I have got 10/41 cells (25% success rate) out of 7 battery packs so far. I have 43 more laptop batteries to go, so maybe my success rate will go up. This seller on ebay posts lots of them, however some are generic so I'm not sure if I will continue buying from him.

I have been setting aside batteries that have a lower than 3v, some of them have less than that. I haven't tested anything else yet (capacity, resistance etc) - what are your other limits?

Also, if you want the best deals possible, skip ebay. Go to your local scrapyard. I was able to purchase laptop battteries for $1.25 PER POUND. not per battery, PER POUND. Even after fully testing all the cells it means I paid only about 30 cents per cell. You are never going to find a price that good on ebay.


I cannot believe I didn't think of this. I contacted an IT Recycle shop and they said I could come get them at $1 USD per POUND! What a deal! Do you have any recommendations when getting them? Did you cherry pick through them?

Sean said:
cstanley said:
This seller on ebay posts lots of them, however some are generic so I'm not sure if I will continue buying from him.

What was the sellers eBay name ?

It would be interesting to compare the quality of cells salvaged from the numerous sellers who all appear to have access to very large sources- I also see many selling obviously old packs.

Coincidentally, yesterday I purchased a batch of 20 from eBay for the first time for a couple of UK pounds per pack - I don't really need any more cells but I'd like to do a proper break down of end cost per usable mAh - or some other useful data.
www.ebay.com/usr/brianm97 I did about 10 more packs and my percentage has gone up to about 50% - I will post the stats when I am done breaking down the whole pack and also do further capacity testing. Right now I am only doing voltage testing. Looks like some of the cells I have are <0v but I have a bunch that I set aside that I will be looking at that had >2.5v

PaulKennett said:
I collected a bunch of data on the correlation between initial voltage and tested capacity - the upshot was there's isn't much - so I'd recommend capacity testing anything you find over 1 volt.

From my sample (from a New Zealand IT recycler) I was getting about 75% usable - depending on how low you are willing to go.


Cheers, Paul

Thanks for the video! This will help me further separate the cells!


I just bought 5 of these to help streamline the testing. What do you guys think about these?
http://www.ebay.com/itm/181862343838


Thanks guys!
 
I get my laptop batteries from a recycler for 1.15 a pound. 50 lbs was about 70 batteries. Of the 300 18650's I've had to re-recycle (I think that's appropriate for the content ;) ) about 30. so, 90% success so far. I did jump into this giant box that was stacking up with batteries and hand picked them myself. I think I got lucky this time and picked the right ones. I just randomly picked one pack that looked good, and got a lot of the same style of packs. Then I got a few other styles just for good measure. It was my first time and I had no Idea what to get or look for. Next time I may try to twist open a pack or two, so I can see what's in them, and then try to grab as many of those types as I can.
 
I've had batches of 100's of laptop batteries with 80% +2400mah, this lot I have now - 10% +2100mah it's destroying my sole
 
hbpowerwall said:
I've had batches of 100's of laptop batteries with 80% +2400mah, this lot I have now - 10% +2100mah it's destroying my sole

Just goes to show you it just depends on where they come from and how old they are :(
 
So many factors but it is what we signed up for :)
 
cstanley said:
hbpowerwall said:
I've had batches of 100's of laptop batteries with 80% +2400mah, this lot I have now - 10% +2100mah it's destroying my sole

Just goes to show you it just depends on where they come from and how old they are :(

I think where they have been stored after they were last used also has something to do with it.
We know cells have a max storage temperature

Datasheet for Samsung ICR18650-28A (as I actually have some of these)
Storage Temperature:
1 year : -20~25?
3 months : -20~45?
1 month : -20~50?
Note : If the cell is kept as ex-factory status (50% of charge), the capacity recovery rate is more than 80%.

So if they've been stored in someone shed/ car for any period of time they are probably screwed. Note the 1 year temperature is easily exceeded in most parts of Australia just in outside air temperature.
 
I think these have been stored in a warehouse for 'sometime' but none the less I'm grateful i have some to process :)


Most are 3.5-4 + volts
 
hbpowerwall said:
I think these have been stored in a warehouse for 'sometime' but none the less I'm grateful i have some to process :)

Most are 3.5-4 + volts

Haha that's awesome! I just got back from a 2 hours drive the other day to pick up about 100 LBS of laptop batteries from an electronics scrap yard. Haven't yet broken any open, but I got go through them and some are brand new unopened laptop batteries! I must say, without doing any testing it looks like I have found a new warehouse! I am currently getting them at $1.50 USD per pound.

A friend and I are trying to come up with a better way to get inside these laptop batteries. This part is the most time consuming, and my least favorite hehe!
 
I've seen people with a heavy enough workbench attach to lumps of wood or steel place the battery between and twist... SOOO fast unfortunately my benches aren't heavy enough to do that.. So just use the wack on ground method
 
hbpowerwall said:
I've seen people with a heavy enough workbench attach to lumps of wood or steel place the battery between and twist... SOOO fast unfortunately my benches aren't heavy enough to do that.. So just use the wack on ground method

The ground method! Haha love it! I too was thinking of twisting it apart. I have no work bench, but might rig something up =P

Have to give your method a try haha!
 
hbpowerwall said:
I've seen people with a heavy enough workbench attach to lumps of wood or steel place the battery between and twist... SOOO fast unfortunately my benches aren't heavy enough to do that.. So just use the wack on ground method

Not sure if you are being totally serious here or not, but don't both "methods" risk stress damage to the cells you are trying to harvest?
 
One hard wack on each corner gets em processed much faster. You don't open 1000's of laptop batteries the slowest way. Rip in -get her done.

Given the choice I'd use the bench twist method to reduce the stressbut can't so wack em it is. You do end up damaging some cells but that's collateral damage

it's not the recommended way,but it's how I choose to do it
 
I've totally adopted the smack it on the ground tactic of opening laptop batteries. It doesn't always work, but 80% of the time it works enough to just tear the outer shell off with your hands and set the cells and board aside while I finish the rest. I usually do between 5 and 10 at a time, and just smacking them saves a decent amount of time. I'd kinda like to see a video of this twist method. I kinda twist mine by hand after the ground pound, just to break more glue, but that doesn't sound like what you are talking about.
 
I think I have processed enough now to have some reasonable stats. Keep in mind I'm just getting started so I have very broad classifications still.
This is the sample from only the ones that I have fully tested.

6 that were completely bad or couldn't take at least 500 mah charge
8 @ 500 - 1500 mah
16 @ 1500 -2000 mah
27 @ 2000 - 2999 mah
8 @ 3000+ mah (all from the same pack)
=======
65 fully tested

So just about 10% complete failure rate for me so far.
Many of my highest capacity ones have come from packs that were either very low voltage on arrival <2.0v or varied voltages within the packs. So I wouldn't go by initial voltage at all except to maybe mark ones that came in under 1 volt.
I also have some suspected bad packs that I opened that I haven't bothered testing yet, so that may raise the bottom end of my curve significantly later.
*Sanyo's (dull red) - 12 of those included in my totals, 2 around 1600mah and the other 10 near 2600mah, and I wont use any of those in my primary packs because I've discovered the don't like any charge above .2C (about 0.4 Amps)

Also worth note is that I live in a very cold state, where folks even climate control their garages, so much friendlier to old Lipos. May skew my totals a bit.

image_osqdnw.jpg
 
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