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18650 Laptop Battery Pulling?

Joined
Mar 29, 2013
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Hey guys! I am in need of lots of 18650s, and i think it would be a bit more economical to buy some laptop batteries (new, hopefully) to extract the 18650s. However, i won't just buy any laptop batteries.

I need:
High quality cells (panasonics, sanyo, sony, etc)
High capacity (preferably at or around 2500mah)
Good value

Any of you do lots of laptop battery pulling, and know of any good laptop batteries to extract from?

I will be using the extracted batteries to make portable phone chargers or e-scooter batteries.

Thanks guys!
-Matt
 





Joined
Mar 27, 2013
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Any genuine laptop battery packs will likely have good cells (Lenovo, Sony, etc) but beyond that I'm no real expert :p I just did two pulls and I have plenty of 18650's now. Good luck :beer:
 
Joined
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I doubt there is much consistancy even within the same brand-

I did one a day ago- it was worn out- of the 6 batts only half would charge past 2.8 vdc and they got quite hot making it tha far--trash

some tips-

take care breaking into the case- they made them hard to open for a reason-- the strips that connect the battteries are sharp-edged- i have cut myself a few times-
I use a dremel tool to make the ends smooth again BUT take care to NOT cut into the plastic coating anywhere it is found-it is a insulator - if they dont charge over night give up-

dispose of properly please-

I do not buy the laptop batts- PC shops save them for me- its possible to buy an outdated NEW battery with like-new cells - IF you shop smart-

I have seen as low as two in a pack and as many as 8-
in some every battery was fine-
others not so many-

I guess the circuitry fails in some before the batteries are past their prime-

Personally I would not pay more than 2$ per battery from a Laptop pack(new)

BUT beware of sellers peddling worn out packs--on greedbay-

'tested and works as it should'


does not tell me very much.

hak
 
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Joined
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I am planning to buy genuine, new, packs.

Lenovo, hp, etc.

Thanks guys
-Matt

Nvm new genuine packs are too much $$$$
 
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Joined
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If you have any old laptops, chances are those batteries will still hold some kind of charge
 
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I have recycled many laptop packs.

Just a couple of precautions with laptop battery packs:

1. Used packs will usually be 3-4 years old before they are available.
Lithium cells usually have a life of ~ 5 years with charging cycles.
These older designs will usually have cell capacities of 2400 mah or so.

2. New packs at a reasonable cost are usually off-brand cells from chinese manufacturers. Lifetime is much less than name-brand cells like Panasonic, Sanyo, LG and Samsung.

3. Some packs that look to be OEM, contain off-brand cells.

If you do get name-brand cells then they are OK,
although capacity is usually about 75% of when they were new.

Some new thinner packs have flat lithium poly cells.

LarryDFW
 
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Quality bare cells would probably end up being cheaper, and you can now buy these in single and small quantities from various sellers.
 
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I have 99% of my batteries from pulling from dead laptop packs (there are still a few good ones inside). Are planning on wiring them all up together? (careful, 3.7V(4.2) per cell adds up very fast! I have micro welded with a few of these as a science experiment... very dangerous, do not try without protective countermeasures!)
If you do want to use many of them together, they need to be the same brand/capacitance/discharge rate/etc. If you want to buy new packs, I would say it's much much cheaper buying the cells separately... not in a laptop pack already. Panasonics are known for being good. I have had good results with Samsungs as well.

I haven't tested Ultrafires a lot, but I see they have 5A and might have seen a 6A 18650
 
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rhd

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I would echo what Larry said.

IMO, harvesting packs makes sense if you're getting used packs that still have decent charge, and they're dirt cheap. $1.50 Sanyo/Sony/Panasonic/etc cells that hold 75% of their capacity are going to be way better than $2.50 "xxxxfire" junkers from China.

But if you're going after brand new, top of the line 3100 or 3400mAh Panasonics, buying individual cells is the way to go. The problem, is that if you buy generic packs, or cheap supposedly OEM packs from China, you'll likely find crappy batteries inside. If you look at the price to buy actual OEM legit packs, you'll be better off buying cells.

Based on a purchase of 6x cells, you can buy Panasonic 3100mAh 18650s new for $6.30 per cell (3x 2-packs, with BulkRate on):
Genuine Panasonic 18650 3.7V 3100mAh Rechargeable Battery - Green (Pair) - Free Shipping - DealExtreme

Before anyone jumps on the DX hate bandwagon, their Panasonics have been tested to death on the flashlight forums, and they're legit. I tested the set I got from them, and confirmed it for myself also.

$6.30 per 3100 mAh Panasonic 18650 is hard to beat. That would basically mean paying $38 for a 6-cell laptop pack.... Can you find a pack at or lower than that price that you know has Panasonic 3100 mAh cells in it? I've gone through some of this math myself, and I always came to the conclusion that buying the single sells was the way to go.
 
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Agree with RHD. Having pulled cells from laptop packs, buying the crapfire, and legit sony, panasonic, or samsung; paying $6.30 for a GOOD new cell is well worth it. You've already spent so much on your laser, why not give it the good nutrition it deserves? :)

The old used cells are great for low current applications though, so I'm not dogging on that either. They're just too old and tired to be pushing our new high current diodes.

I'm still looking forward to getting my hands on those IMRs and testing those out.
 





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