Bad laptop pulls

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Boaz
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Bad laptop pulls
i was in lowes the other daybuying plumbing supplies so i went over to tghe recycling bin and grabbed a couple handfulls of batteries to play with …… i don’t think i’ve ever seen batteries as bad as the LGDBB11865 from a Dell laptop pack Six batteries /nice color/solid green kind of like a samsung25R . I was a bit excited to see they had a 3,7V charge on all six so I cleaned them up a little too much before charging. The first clue was when placed on the liito-kala 500 at a half an amp they started to climb very quickly….kind of like when the cell has an under 2v charge . I didn’t note the time it took to charge but all 6 terminated at 4.20V The next day I decided to drop one in a light and had my meter handy, so I checked voltage …..3.94V//3.90V///3.94 etc …

I’ve never seen a battery drop so far so fast just sitting ….The internal resistance before charging was 125 which I thought was not great but not horrid either . i’ve torn apart lots of battery packs but have never seen anything drop that far that fast .

Has anyone seen this before ? If a battery seems to charge too fast is that a sign it’s bad ?

καὶ τὸ φῶς ἐν τῇ σκοτίᾳ φαίνει καὶ ἡ σκοτία αὐτὸ οὐ κατέλαβεν

Milan
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Worn batteries have not just higher internal resistance and lower capacity, but they are also – how to describe it – kinda “slow”. Meaning they cannot be charged or drained in few hours like new cells, so even half amp is too much for them.

To get full capacity out of them, or full charge into, it will require longer time – at least 4 – 5 hours, but the lower the better. Charging such batteries with 0,1A is the best. Also using them for low loads or intermittent use (so they can “rest”) is ideal.

snakebite
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the lg “spicy mustard” colored cells from dell packs are worse.
laptops are hard on batteries and some age worse than others.
panasonic and samsung being the best.

Barkuti
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Buying cheap replacement laptop battery packs may be worth it, for cell harvesting I mean.

Used packs? Not worth the required cell assessment and tune up time I believe, though it all depends. 

 

Cheers Smile

everydaysurvivalgear
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I got some laptop pulls here and they are okay. Both Sanyo cells the lowest voltage i encountered was 1.8v.

They all still work but not the best quality or i should low amperage draw more made for longevity and not power. Actually the better cells came from an old Lenvo laptop they are very well aged lol. But still work good! Sanyo quality.

My LG HG2 are wearing bad maybe its just an LG thing?

snakebite
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as for digging in the recycle bin for packs many such packs are worn out.
but some get recycled due to a busted laptop or a bricked bms.those can give some very good cells.