6 Cells harvested from a 13 years old Dell laptop.

Always learning

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Jul 28, 2020
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Im dismantling and laptop and I harvested 6 cells from the battery pack.
This laptop was in heavy use for about 3 years and then it was sitting in the shelf for about 10 years (yes, no joke here).
A few weeks ago when I switched it on, a warning showed up that the battery pack needs replacing. Obviously Im not going to replace anything, I just dismantled it :).
These cells are of the same size as 18650 cells, however, there is no mention whatsoever about 18650 on the wrapping. I decided to peel the wrapping off in order to figure out if there was any more info under the wrapping but guess what? No, the info on the wrapping is the same as in the cell itself.
There is a C written in the middle of the cell and then some sort of reference JKLFK47 and then 136988, also there is K45A engraved on the wrapping.
From the cell data base, in this forum, judging by the colour and the green ring at the top, it seems to be a Sanyo UR18650FK.
However, as I said above, there is no mention on the cell about Sanyo UR18650FK
I wonder if I can do a capacity test on these cells using my LiitoKala Lii-500 because there is no mention about 18650 on the cell itself.

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there is some writing on the wrapper only you must have good eyes to see it.

look at cell database and look for sanyo with green isolator ring
 
If it looks like an 18650 cell and walks like an 18650 cell- its an18650 cell! I have some cells even older out of a Fujitsu laptop power pack :)
There is such a thing as LifePO4 cells in an 18650 format but these look likeRed Sanyo 18650 Lithium-ioncells.
Just run the normal test protocols on old cells - e.g. if v to low discard, check for heating while charging, etc... and you can definitely use them for something - maybe a flashlight -if they test out OK.
 
barry said:
there is some writing on the wrapper only you must have good eyes to see it.
If there was any more info on the wrapping, possibly it faded over the years I would assume.
I even put the cell under the light in order to see if I could findany other letters of numbers engraved but there was nothing apart from the above information


OffGridInTheCity said:
If it looks like an 18650 cell and walks like an 18650 cell- its an18650 cell! I have some cells even older out of a Fujitsu laptop power pack :)
There is such a thing as LifePO4 cells in an 18650 format but these look likeRed Sanyo 18650 Lithium-ioncells.
Just run the normal test protocols on old cells - e.g. if v to low discard, check for heating while charging, etc... and you can definitely use them for something - maybe a flashlight -if they test out OK.
Not sure if "walks like an 18650 cell" but for sure it rolls like a 18650 cell :).
The voltage in all of them still stands at around 3.7V. Can I use them like this in a flashlight or should I spot weld a BMS in them? I recall somewhere onYouTube, some guywas testingunprotected laptop cells in flash lights and the batterystoppedproviding power way before it reached the lowest discharged voltage.
As you guys see, I'm a new bee in this "18650 cells world". I bought a DIY spot welder, nowI need to start practicing.
[size=medium]I was convinced that all 18650 cells had written 18650 on the wrapping but apparently I was wrong.

I have one Ryobi18V battery packthat shows LGDAHA 11865 and after reading here on the cell database, it turns out that it is an 18650 after all, (ICR18650HA1)
[/size]Thanks guys for all your help.
 
Alwayslearning said:
barry said:
there is some writing on the wrapper only you must have good eyes to see it.
If there was any more info on the wrapping, possibly it faded over the years I would assume.
I even put the cell under the light in order to see if I could findany other letters of numbers engraved but there was nothing apart from the above information


OffGridInTheCity said:
If it looks like an 18650 cell and walks like an 18650 cell- its an18650 cell! I have some cells even older out of a Fujitsu laptop power pack :)
There is such a thing as LifePO4 cells in an 18650 format but these look likeRed Sanyo 18650 Lithium-ioncells.
Just run the normal test protocols on old cells - e.g. if v to low discard, check for heating while charging, etc... and you can definitely use them for something - maybe a flashlight -if they test out OK.
Not sure if "walks like an 18650 cell" but for sure it rolls like a 18650 cell :).
The voltage in all of them still stands at around 3.7V. Can I use them like this in a flashlight or should I spot weld a BMS in them? I recall somewhere onYouTube, some guywas testingunprotected laptop cells in flash lights and the batterystoppedproviding power way before it reached the lowest discharged voltage.
As you guys see, I'm a new bee in this "18650 cells world". I bought a DIY spot welder, nowI need to start practicing.
[size=medium]I was convinced that all 18650 cells had written 18650 on the wrapping but apparently I was wrong.

I have one Ryobi18V battery packthat shows LGDAHA 11865 and after reading here on the cell database, it turns out that it is an 18650 after all, (ICR18650HA1)
[/size]Thanks guys for all your help.



3.7v is fantastic. That means they are likely healthy. I'd still do a charge/discharge test and check for heaters - but I'd bet they are perfectly good for low amp use like flashlights. I wouldn't do ebike (high amp discharge) type applications - likely be dissapointed.
 
OffGridInTheCity
Alwayslearning said:
barry said:
there is some writing on the wrapper only you must have good eyes to see it.
If there was any more info on the wrapping, possibly it faded over the years I would assume.
I even put the cell under the light in order to see if I could findany other letters of numbers engraved but there was nothing apart from the above information


OffGridInTheCity said:
If it looks like an 18650 cell and walks like an 18650 cell- its an18650 cell! I have some cells even older out of a Fujitsu laptop power pack :)
There is such a thing as LifePO4 cells in an 18650 format but these look likeRed Sanyo 18650 Lithium-ioncells.
Just run the normal test protocols on old cells - e.g. if v to low discard, check for heating while charging, etc... and you can definitely use them for something - maybe a flashlight -if they test out OK.
Not sure if "walks like an 18650 cell" but for sure it rolls like a 18650 cell :).
The voltage in all of them still stands at around 3.7V. Can I use them like this in a flashlight or should I spot weld a BMS in them? I recall somewhere onYouTube, some guywas testingunprotected laptop cells in flash lights and the batterystoppedproviding power way before it reached the lowest discharged voltage.
As you guys see, I'm a new bee in this "18650 cells world". I bought a DIY spot welder, nowI need to start practicing.
[size=medium]I was convinced that all 18650 cells had written 18650 on the wrapping but apparently I was wrong.

I have one Ryobi18V battery packthat shows LGDAHA 11865 and after reading here on the cell database, it turns out that it is an 18650 after all, (ICR18650HA1)
[/size]Thanks guys for all your help.



3.7v is fantastic. That means they are likely healthy. I'd still do a charge/discharge test and check for heaters - but I'd bet they are perfectly good for low amp use like flashlights. I wouldn't do ebike (high amp discharge) type applications - likely be dissapointed.

No ebikes here, I like my cars. I will do a charge/discharge test when I have time to be around in order to check them every few minutes for heaters. You guys mean heaters when they are really hot to the touch? And obviously ithappens when they are charging after discharge, right?
 
It most certainly looks like a Sanyo UR18650FK Possibly a UR18650FB both are 2400mAhcells.

I find that sometimes (butnot all Sanyo cells)mostwill have a very lightly stamp on them. To bring it out I take a big fat black sharpie and rub on it with my finger.
Makes a mess on the finger but hey it's a sacrifice I am willing to take.

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Also if you have the capability take an IR reading of the cells If it fall between these numbers they will most likely be good.

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Wolf
 
Alwayslearning said:
OffGridInTheCity
Alwayslearning said:
barry said:
there is some writing on the wrapper only you must have good eyes to see it.
If there was any more info on the wrapping, possibly it faded over the years I would assume.
I even put the cell under the light in order to see if I could findany other letters of numbers engraved but there was nothing apart from the above information


OffGridInTheCity said:
If it looks like an 18650 cell and walks like an 18650 cell- its an18650 cell! I have some cells even older out of a Fujitsu laptop power pack :)
There is such a thing as LifePO4 cells in an 18650 format but these look likeRed Sanyo 18650 Lithium-ioncells.
Just run the normal test protocols on old cells - e.g. if v to low discard, check for heating while charging, etc... and you can definitely use them for something - maybe a flashlight -if they test out OK.
Not sure if "walks like an 18650 cell" but for sure it rolls like a 18650 cell :).
The voltage in all of them still stands at around 3.7V. Can I use them like this in a flashlight or should I spot weld a BMS in them? I recall somewhere onYouTube, some guywas testingunprotected laptop cells in flash lights and the batterystoppedproviding power way before it reached the lowest discharged voltage.
As you guys see, I'm a new bee in this "18650 cells world". I bought a DIY spot welder, nowI need to start practicing.
[size=medium]I was convinced that all 18650 cells had written 18650 on the wrapping but apparently I was wrong.

I have one Ryobi18V battery packthat shows LGDAHA 11865 and after reading here on the cell database, it turns out that it is an 18650 after all, (ICR18650HA1)
[/size]Thanks guys for all your help.



3.7v is fantastic. That means they are likely healthy. I'd still do a charge/discharge test and check for heaters - but I'd bet they are perfectly good for low amp use like flashlights. I wouldn't do ebike (high amp discharge) type applications - likely be dissapointed.

No ebikes here, I like my cars. I will do a charge/discharge test when I have time to be around in order to check them every few minutes for heaters. You guys mean heaters when they are really hot to the touch? And obviously ithappens when they are charging after discharge, right?



Wolf said:
It most certainly looks like a Sanyo UR18650FK Possibly a UR18650FB both are 2400mAhcells.

I find that sometimes (butnot all Sanyo cells)mostwill have a very lightly stamp on them. To bring it out I take a big fat black sharpie and rub on it with my finger.
Makes a mess on the finger but hey it's a sacrifice I am willing to take.

image_wotmha.jpg

image_gpmwun.jpg


Also if you have the capability take an IR reading of the cells If it fall between these numbers they will most likely be good.

image_arwxjt.jpg


Wolf
I checked these bloody cells :) afew times todayand there is absolutely nothing written or engraved on the wrapping apart from what I mentioned in the first post and inside the yellow circle I marked in the picture :K45A. There always an odd one somewhere... :)
 
OffGridInTheCity said:
3.7v is fantastic. That means they are likely healthy [...]

Maybe or maybe not. They may have been charged when the OP powered on the laptop, in which case we don't know how low they went while they were idle for 10 years (and I don't recall whichBMS Dell was using in their packs in those days so it's not clear how it would handle such).

The way I handle such cases is to measure the pack before charging it in the laptop. Below is a photo that shows what pins you need to short to enable pack output (iirc pin 4 is SYSTEM_PRESENT and the two longer pins on both end are NEG and POS, so you need to short SYS_PRE to GND to enable output). One you have access to the pack voltage you can determine the average cell voltage, and even run an IR test if you desire.

Of course with such a connector you don't even need to teardown the pack if you wish to use it as a 12V powerbank (but you will need a special charger to charge it). See herefor more.


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Wolf- I forgot to say in the previous comment, the only way or equipment I have to find the IR is using my LiitoKala Lii-500 but a few people say here and there that the IR readings in these sort of[size=medium]charger[size=medium]s are not 100% reliable.[/size][/size]


gauss163 said:
Alwayslearning said:
3.7v is fantastic. That means they are likely healthy.

Maybe or maybe not. They may have been charged when the OP powered on the laptop, in which case we don't know how low they went while they were idle for 10 years (and I don't recall whichBMS Dell was using in their packs in those days so it's not clear how it would handle such).

The way I handle such cases is to measure the pack before charging it in the laptop. Below is a photo that shows what pins you need to short to enable pack output (iirc pin 4 is SYSTEM_PRESENT and the two longer pins on both end are NEG and POS, so you need to short SYS_PRE to GND to enable output). One you have access to the pack voltage you can determine the average cell voltage, and even run an IR test if you desire.

Of course with such a connector you don't even need to teardown the pack if you wish to use it as a 12V powerbank (but you will need a special charger to charge it). See herefor more.


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Here it is what was attached to these cells.

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Alwayslearning said:
..............a few people say here and there that the IR readings in these sort ofchargers are not 100% reliable..............

He he yeah that's me and some others.

Take 3 or 4 readings of each cell make sure you have good contact (sorry I'm sure you know that) and average it.
Let me know what your results are. Or compare them to this sheet.
These are all the FB and FKs I testedwith a Liitokala as you can see the IR readings are all over the place especially some of the FKs
Wolf


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>You guys mean heaters when they are really hot to the touch? And obviously ithappens when they are charging after discharge, right?
Yes. Just touch them as then are mid-charge and then especially as they near full charge. Warm is fine - but too hot to touch is not good. I'd do this for all 6 cells because you don't know anything about them in a general sense.

When I process 1,000(s) of cells of the same order/type - after a few hundredthere will typically be a pattern of IR, % mah per original, etc. For example I'm processing RING packs and after processing 800 of them.. and they are fine, 100%, low IR, and 2018 date-codes... I've stopped worrying about heaters and just do a quick touch test as they near full charge. A while back I did a batch of 'raw' NCR18650A(s) and 20% of them were heaters... with a pattern like that it's goodto check for heaters at multiple stages of charge.
 
Wolf said:
Alwayslearning said:
..............a few people say here and there that the IR readings in these sort ofchargers are not 100% reliable..............

He he yeah that's me and some others.

Take 3 or 4 readings of each cell make sure you have good contact (sorry I'm sure you know that) and average it.
Let me know what your results are. Or compare them to this sheet.
These are all the FB and FKs I testedwith a Liitokala as you can see the IR readings are all over the place especially some of the FKs
Wolf


image_uvggqc.jpg
Man, the first second I had a look at your excel data, I thought, wow, what am I looking at? :) I need to look at it another 5-10min to see if I can understand it, specially for me, a newbee. :)


OffGridInTheCity said:
>You guys mean heaters when they are really hot to the touch? And obviously ithappens when they are charging after discharge, right?
Yes. Just touch them as then are mid-charge and then especially as they near full charge. Warm is fine - but too hot to touch is not good. I'd do this for all 6 cells because you don't know anything about them in a general sense.

When I process 1,000(s) of cells of the same order/type - after a few hundredthere will typically be a pattern of IR, % mah per original, etc. For example I'm processing RING packs and after processing 800 of them.. and they are fine, 100%, low IR, and 2018 date-codes... I've stopped worrying about heaters and just do a quick touch test as they near full charge. A while back I did a batch of 'raw' NCR18650A(s) and 20% of them were heaters... with a pattern like that it's goodto check for heaters at multiple stages of charge.
Yes, I was planning to check/test all of them. I guess that will be a long day. Better put a few movies handy next to the charger. :)
 
Alwayslearning said:
Here it is what was attached to these cells [...]

Probably they didn't go so low to be dangerous or else the BMS would refuse to charge them. Iirc those old Sanyo's are LiCo so 3.7V should be around 15% SOC, so it's possible that's as low as they self discharged over 10 years, esp. if they started out high enough and the BMS has a very low power deep sleep mode, since self-discharge rates decay exponentially. For example, self-dischargemay be around 1mA at full charge, buthundreds orthousands of times less near empty.

Unfortunately a large portion of that self-discharge may bepermanently lost capacity. As a double whammy the IR is also increased, so not only do you have less chemical capacity left, but you may only be able to access a small portion of that remaining capacity due to the large I*R drop under nontrivial loads. You can't escape the grim cell reaper...

The only way to be sure is to run some capacity tests at the current(s) you expect during use.
 
OffGridInTheCity said:
> You guys mean heaters when they are really hot to the touch? And obviously ithappens when they are charging after discharge, right?
Yes. Just touch them as then are mid-charge and then especially as they near full charge. Warm is fine - but too hot to touch is not good. I'd do this for all 6 cells because you don't know anything about them in a general sense.

The temperature where it starts becoming an issue is around 60C, or about 140F. You could go safer on this to only 50C (122F). A lot of the datasheets state that "operating" temps not to exceed 85C. That's still quite hot.
If you can't keep your hand on it longer than a few seconds, it's too hot. I personally rather use the back of my hand as it's more sensitive to temperatures.


I would say to read the datasheet to find out what the temps are, but in this case, it's kinda hard to do since you don't know what cell it is to begin with.
 
Alwayslearning said:
Man, the first second I had a look at your excel data, I thought, wow, what am I looking at? :) I need to look at it another 5-10min to see if I can understand it, specially for me, a newbee. :)

Oopssorry yea there is a lot there esp. if you have never seen one of my sheets. Sorry

Columns A - H is just cell info pulled from the database.
Columns I - N is cell parameters as in IR (I) pre test voltage (J) what the tester IR showed (K) the tester used (L) the results in mAh (M) and the SOH in percentage of capacity remaining.(N)
ColumnsO - R is 30 day retest of IR and V. (There we find SD (Self Discharge) cells.
ColumnsS - Y is just more manufacture info.

Didn't mean to overwhelm. :)
Wolf
 
Wolf said:
Alwayslearning said:
Man, the first second I had a look at your excel data, I thought, wow, what am I looking at? :) I need to look at it another 5-10min to see if I can understand it, specially for me, a newbee. :)

Oopssorry yea there is a lot there esp. if you have never seen one of my sheets. Sorry

Columns A - H is just cell info pulled from the database.
Columns I - N is cell parameters as in IR (I) pre test voltage (J) what the tester IR showed (K) the tester used (L) the results in mAh (M) and the SOH in percentage of capacity remaining.(N)
ColumnsO - R is 30 day retest of IR and V. (There we find SD (Self Discharge) cells.
ColumnsS - Y is just more manufacture info.

Didn't mean to overwhelm. :)
Wolf
30 day retest of IR and V- AmIright to assume this means using the nortest setting on the litokalla? I mean charge, discharge and charge again?
 
Alwayslearning said:
30 day retest of IR and V- AmIright to assume this means using the nortest setting on the litokalla? I mean charge, discharge and charge again?

No after doing the NOR test the first time and getting the mAh results we let the cell sit for ?30 days at full voltage and recheck voltage.If the V drops below 4.1 V the cell may be a SD.
I unfortunately am very anal and check the V and IRwhen the cell comes out of the "NOR" test and record it. Then again in 30 days.
I know crazy right?
This is my new testing method sheet for each cell I test. I think the column headers explain it well
Wolf

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Korishan said:
"but in this case, it's kinda hard to do since you don't know what cell it is to begin with".
Yes, that is why I was asking previously if these cells can be tested for capacity using my Liitokala charger. They lookexactly the same as a Sanyo18650but I don't want to end up with a flare inside my house. The wife wouldn't be happy :)


Wolf said:
Alwayslearning said:
30 day retest of IR and V- AmIright to assume this means using the nortest setting on the litokalla? I mean charge, discharge and charge again?

No after doing the NOR test the first time and getting the mAh results we let the cell sit for ?30 days at full voltage and recheck voltage.If the V drops below 4.1 V the cell may be a SD.
I unfortunately am very anal and check the V and IRwhen the cell comes out of the "NOR" test and record it. Then again in 30 days.
I know crazy right?
This is my new testing method sheet for each cell I test. I think the column headers explain it well
Wolf

image_fcujba.jpg
Do you have a specific equipment to measure the IR? Or you just rely on the readings that the charger gives to you?
 
Wolf said:
[...] after doing the NOR test the first time and getting the mAh results we let the cell sit for ?30 days at full voltage and recheck voltage.If the V drops below 4.1 V the cell may be a SD

It might be possible to test for self-discharge much more quickly for overdischarged cells. One way to measure the self-discharge rate at voltage V is to float charge to V volts then wait for the charge current to stabilize. The stabilized current is the self-discharge rate. But it may take a long time to stabilize (weeks). Maybe at very low SOC we can get it to stabilize much more quickly. If so, this may yield a very quick way to test for self-discharge. If anyone has such cells and is interested in testing this then let me know and I can explain it further if need be. The only hitch is that possibly this might require more precise equipment than hobbyists typically have.
 
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