Large number of laptop batteries

Why do you have to compare high and low current discharge opposed to just testing high current discharge?

The thought of testing that many batteries make me giggle…. So what would be the best method to do that?

Please see post #8, I would just end up retyping the same thing over again.

So not really worth it :slight_smile:

It's an awful lot of work to end up with 2 out of every 10 usable only in a low-drain application. And a lot of scrap to haul off to the recycling center. Used laptop packs don't get replaced for no reason.

New, never-charged, never-used packs that have been in storage, just overstock stuff that was taking up space in a warehouse somewhere, for a laptop model that's now obsolete, that somebody bought in bulk at auction and is unloading for cheap on ebay can be excellent value. Used up clapped out laptop packs are almost always not.

These were from a laptop upgrade for a large group. Some of the batteries are new some are old. But I am the kind of person that hates to see things go to waste. Thus as a hobby endless hours to throw at a project. I know you are trying to save me from a lot of useless work but if I wanted that I don’t think I should be on a flashlight modding forum.

Order 5 chargers that can run charge and discharge tests and just run them while I work? Maybe 10 chargers lol. Other than that I might just pull what I could use in the next couple years and toss the rest. Those are the options. If I toss them I would love to see them go out to people that would like them to tinker with also. So any help you could give would be great, other than “Run away as fast as you can and save your sanity!”

I understand your standpoint but at work I deal with bones and bugs so playing with electronics is just a sort of an escape so the work while tedious would be a welcome relief.

Well hey man I live in Richmond Virginia and have a Honda civic

Just saying :slight_smile:

Let me see how these tests pan out. But I will certainly have more than I can use. So shoot me a pm and we can work something out.

Roger

If you do low and high current tests on all of them, with a hobby charger that tests internal resistance, you'll get 1 or 2 batteries per day per charger. That's a lot of money and/or time. If you're not doing it for either one, then go for it. 10 good chargers and power supplies will cost you around $1000. Even if all 500 batteries are usable, you'd have a hard time selling them for $2 each, but some will be bad, and shipping/supplies isn't free. I'm testing a batch of cells right now, and even though the batteries are free, it's not worth it for the money, and has made me respect the contributions to our hobby that HKJ has made so much more.

Yes, it's a hobby, but I think you'll be much happier if you put the time towards modding flashlights instead of the monotony of testing hundreds of batteries, 24/7, every day for months to years.

the neon green are bak.
aftermarket and maybe low use?
the rest?
each pack may have a different amount of wear.
there are utils to read the “wear”
that is untill you strip the packs!
and assuming you can borrow a laptop that takes the pack.
if those were mine i would check each pair of cells with an esr meter after they pass the safe voltage test.
i can usually tell if they are worth charging and testing further.
generally the newer the datecode the better condition they will be in with few exceptions.
are they worth anything?
not on ebay as unknown used packs.
but if you have the time and lots of friends into lights they can be good tradebait after you weed out the duds.
i use a 12 cell gang holder i built and a triton to do the charging.
so 24 cells at a time as i leave them paired.charge and set aside a few days.if they drop a lot thats a sign they are tired.
like starting at 4.17(typical for my setup)and a week later 4.0 or less.recycle those.the ones that stay up are usually quite usefull.
nw you seperate the pairs and discharge a few at 1a.this gives a good idea for their condition.note at this point what you have are always better than ANY “whateverfires”.
i have lots of flashlight and vape mod friends who have been running recycled cells i have processed this way.they save money and it feeds my hobby a bit.
esp when said friends have modded srk!i go further with those and mark cells that were from the same pack.not perfectly matched but better than random used calls.
so now you know what to do.or pass them on to others that want to do this.esp if this is over your head and you just need some good ones to use.i have done that for folks too.everybody wins.
just think that if this catches on in a big way whateverfire brands will get worse as the quality of scrap cells drops due to us weeding out the good ones!

Hagg911,
when you are pulling batteries, get the pictures and battery info over to here to this thread, i am trying to build a community Laptop Pull overview thread.
community laptop Pull overview thead

Ok I get it lots of work and little to no return. Let me try it this way does anyone have a step by step process they use for laptop pulls.

Snakebite could I get a picture of your charging setup? What are you using to do the discharge rates?

It depends on the pack. On some I slip an exacto knife into the back seam to break the glue, then work up to the front. Sometimes the part with the pcb doesn't open at all. On others I'll start where the contacts are, and wedge it open with a screwdriver. Once it's open, cut the leads, pull off the tape, pull off the solder tabs, grind down the solder tabs very carefully with a dremel, clean off the adhesive, rewrap if necessary, test voltage, charge the cells worth keeping, discharge to 3.0V with a hobby charger while logging, charge back to storage voltage with a hobby charger.

You might try giving them away here. Ideally for you, without testing. Ask the recipients to pay for shipping and supplies if you wish. Downlinx and I are giving away cells, and that's probably going to be more than enough to keep me busy, otherwise I would have offered to do this with you.

I usually start by peeling off the top label and expose the Cross section bars. I then start cutting the bars(so i can see if i go to deep with the knife or dremel tool. Then i take an exacto or dremel to the outside of the case

I think i have the opening down on this group.
After pull,

  1. Check voltage, above 2.7v keep.
  2. Charge to full, Check voltage and record
    2.a Check 1 hour later
    2.b Check 1 day later
    2.c Check 1 week later
  3. All that kept charge with minimal drop in V keep (.01-.1v?)
  4. Use charger to do a charge discharge charge cycle to see capacity.
  5. Profit with gold raining from the sky and the horn resounding blowing in the winds

Please add to the list, any help is appreciated.

Hahahaha profit.

Yeah I would consider a opus dream charger or the liikota. This will give you the ability to charge, get an idea of the internal resistance with minimal effort, and do a discharge to test the capacity. It’ll be slow, as those are 4 or 2 battery chargers (respectively) but you might can find enough decent cells to sell and break even on the charger’s cost, and then every cell after that is tested and free (to you).

The number of total packs that was suggested on hand was in the neighborhood of 1000. :party:

cool!
lets do the worlds first 18650 powered golfcart!
a baby tesla.
and here is the holder i use for the paralel charger.
i have one set up with 3 of these glued end to end.i used #14 zipcord and bananna plugs to connect to the triton.the triton does the discharge tests also.
for a cheap start get a genuine imax b6.
the difference between the original and the knockoffs is about $10

I wouldn't open any of them .I'd sell them on ebay and figure out how many packs you can fit in a 580 no weight limit priority post box and price quantities of packs so people would want to buy like 4 or 5 ?? at a time ..My general guess is a used unknown laptop pack might be worth 3 to 5$ ...If i had 1000's i'd be trying to sell them in quantities of 5 and 10 at like 20$ for 5 and 35$ for 10 packs . Like Comfey chair said opening up and claening them up for your own personal use is tough enough ...Ask anyone who's done 2 or 300 cells before .....1000 packs ?? no way in hell I'd consider opening any of them unless i knew it was a new old stock unused original pack with desirable cells in it . Even in quantities i don't think there's a real big market for them . I'd offer them here and on ebay and open a few for fun for yourself .. after 5 packs you won;t want to open another for 5 more months ..I'm guessing the people who have hoarder stashes here on blf have spent years to get to a couple hundred batteries /////90% of which would be new unused oem packs and have thrown out another couple hundred as well .. Not to mention their stash of un-opened packs they hide from their wives .