Am I the only one? Re used 18650 laptop cells? and iCharger

NeilP

Enlightened
Joined
Jun 17, 2013
Messages
291
Location
Jersey Channel islands UK
Just wondered if I am the only one? or if there are other tight fisted ones out there?


Just come back from a trip to the local dump/recycle center with 3 old laptop packs.

The old laptop packs usually fail because one single cell or parallel group dies. the rest of the cells still give good output.

Ok so not 3Ah, but I here have 19 seeming usable cells.

Not done discharge tests on them with the iCharger yet, but going by past results, I get better than 80% usable cells of 2 Ah or more per cell.


http://paisnel.co.uk/upload/18650.jpg
 
Last edited:

markr6

Flashaholic
Joined
Jul 16, 2012
Messages
9,258
It's fun to get use out of "junk". I pulled 6 out of an old Dell. Only 2000mAh but they seem to be in pretty good condition. I just keep them as backup, and use one in a green laser pointer which doesn't use much power anyway (at least much less than my flashlights)
 

ChrisGarrett

Flashlight Enthusiast
Joined
Feb 2, 2012
Messages
5,725
Location
Miami, Florida
I've got 8 Sony 2000mAh cells from a Vaio pack from '04, which are date coded at 2002.

They ALL came out of the dead pack a 3.7x+ volts and all charged up just fine to about 4.18v and then settled at 4.14v-4.15v. I've let them sit for a month and they still measure at ~4.15v, so they're apparently healthy cells, albeit used ones.

Now, I have an article from a guy who builds E-scooter battery packs and is very familiar with pulled cells and he said you just need to be aware that laptops put a lot of strain on cells inside the pack and heat can weaken them above and beyond normal duties.

His advice is to not charge these cells up at a high rate and two, don't discharge the cells at anything over .5C, which in my case is 1A, so while I've tested them all out with my Convoy lights (knowing that medium is 40% and my driver boards are 2.8A on high,) I've done so on medium, not high and the calculations seem to be in correct for very healthy and usable cells.

The caveat is to not treat them as you would a new cell and don't go throwing them into your monster light that draws 7A at the tail.

I have two more of the Vaio packs, but I haven't bothered opening them up.

Chris
 

NeilP

Enlightened
Joined
Jun 17, 2013
Messages
291
Location
Jersey Channel islands UK
I have just ordered some sprung holders from e-bay , two 4 cell series holders and a 2 cell series holder to make up a 10 s pack.
The icharger I have can balance charge and discharge test 10 cells at a time so I will be able to check out cells quicker.

At present I have to solder on to the spot weld tabs and it is a pain and takes an age.
Having the quick release holders I can test cycle cells a lot quicker.

I work on the other theory with these cells, they are free and I give em a hard time...no difficult to get another 20 -30 of them if need be. The ones that last...well they last..the ones that die can be binned.


EDIT don't bother with these crappy plastic holders, the connections are utter crap. can't charge with them as the voltage on the balance port fluctuates too much even with the charger in monitor mod and no current being drawn.

The plastic holders are OK, but you will have to rip out the connections and fit some brass bolts or contacts...probably easier just to build your own holder from the start.
 
Last edited:

ChrisGarrett

Flashlight Enthusiast
Joined
Feb 2, 2012
Messages
5,725
Location
Miami, Florida
Just be careful running them in series and under high loads, is all that I would caution. They're probably 'tired' cells for you to begin with.

Chris
 

condor22

Newly Enlightened
Joined
Feb 1, 2014
Messages
25
Guilty, I did............have some of the GCR18650DA that are rated 2450mAH per the data sheet. I googled. Mine perform excellent. Good luck! :poof:
 

NeilP

Enlightened
Joined
Jun 17, 2013
Messages
291
Location
Jersey Channel islands UK
No, sorry Norm, did not search this time.
I did a search when I first posted a few days ago about modding my old Maglite AAA but this time no.

I had just got back to the workshop, with my haul of 'new' cells from the dump and this was the first time on line with the rebuilt XP SP3 workshop computer. The day before, I had cut some trees to allow my 500 meter home built WiFi bridge antenna system with hacked ddWRT routers turned AP's to work again. So I had a running computer, working WiFi back to the house, so Internet AND new cells to play with.
I just posted from the sheer excitement of it all 😃. But did end up double posting 😔


All these cells now and not enough powerful kit to use them with.




Sent from my iPhone using Candlepowerforums
 

NeilP

Enlightened
Joined
Jun 17, 2013
Messages
291
Location
Jersey Channel islands UK
Just be careful running them in series and under high loads, is all that I would caution. They're probably 'tired' cells for you to begin with.

Chris


Yes, I'll be careful with them. Give them
all a couple of charge/discharge cycles on the iCharger. Run them up to 1C and see how they hold out.
not had much experience with these little baby cells in Lithium before . Up to now just been playing with LiPo model aircraft packs put together as big e-bike packs. 24 series 4 parallel 100volt 20 Ah with 50C. burst discharge rates 😳
Accidentally short circuit those buggers and you sure as hell know about it. A 1000 amp flash between the wires you are holding certainly wakes you up on a cold morning when you are tired and make a mistake while connecting the pack to the bike 😖
 

swampgator

Enlightened
Joined
Aug 29, 2006
Messages
777
Location
Gatorville, Florida
I actually have far too many of them now, just keep grabbing more..had a count in one box today, about 60 of em.

My brother in law just gave me 9 battey packs. So far I've harvested close to 60 or so as well. I'll get a full count later today. So far only a handful have proven to be faulty.
 

johnmeyer

Newly Enlightened
Joined
Aug 3, 2011
Messages
25
Just had a bad experience with my first 18650 cells which I purchased as a kit with a cheap charger on Amazon (yes, I know ...). Returned the charger and batteries, but then wondered what to use with the "3800 lumen" knockoff flashlight I bought. Read this thread, and immediately opened up one of several "dead" laptop Lion packs I have lying around. The old Fujitsu pack had six 18650s, with pairs in parallel. One cell was 0.00 V, which is probably why it would no longer hold a charge. The others were fine, even though the pack hasn't been charged for several years. Put the four best cells in my light, and works great.

So now all I need to do is get a good charger.
 

NeilP

Enlightened
Joined
Jun 17, 2013
Messages
291
Location
Jersey Channel islands UK
Tha is great to hear.

I'd certainly buy a dedicated 18650 charger, have seen plenty mentioned on here..Xtar I thing kwas the name.

But also get a Hobby charger,like an iCharger 3010b, that allows you to test the cells from these packs..you can do discharge graphs etc. and plot the exact ah capacity of the cells
 
Last edited:

johnmeyer

Newly Enlightened
Joined
Aug 3, 2011
Messages
25
I'd certainly buy a dedicated 18650 charger, have seen plenty mentioned on here..Xtar I thing kwas the name.
Thanks for that recommendation. I am reading other CP threads right now about what charger to get. The Xtar XP, VP, and WP chargers get lots of recommendations. However, the whole point of the original exercise was to get some "cheap thrills" with a $50 knockoff of a $300 high-lumen flashlight. The light is going to be used only once in awhile, and I don't want to spend $$$ because this cheap light is the only thing I have which uses 18650s.

As of this moment, the Nitecore i2 or i4 seem like the best bet for what I need. I already have a very nice Opus BT-C2000 (which I use every day) for my AA/AAA batteries, so I don't need another "ultimate" charger for this simple task. I only need something that is safe and reasonably quick.
 

NeilP

Enlightened
Joined
Jun 17, 2013
Messages
291
Location
Jersey Channel islands UK
Top