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ArcticMyst Security by Avery

Alternate source of 18650 batteries...

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Dec 20, 2009
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Hello all,

I have been on LPF for a while now ( sorry I haven't posted that much ( I don't want to re post info that someone else already has posted)), and I have noticed there are a lot of questions about getting/finding 18650 batteries. I was not sure where to post this ( this could probably go in every forum), I do know that a lot/most of the 445's (mine included), 405's, and a lot of portable green lasers are powered by 18650s. I have personally experienced the strobing effect caused by crappy batteries. I have found a solution to locating 18650 batteries just today. I just went to a local battery store, Batteries Plus, and I asked them if they had 18650's; The manager said they don't carry them, however, they had some in the store. I asked the guy where they came from, and he replied "These came from laptop batteries, the battery pack that plugs into every laptop". Apparently inside every laptop battery pack there are 4-6 18650's inside each pack!!!!! The guy at the store actually gave me all the ones he had for FREE. I had an old laptop battery upstairs in my spare room, so I went an popped it open and low and behold, 4 18650's inside!!! I know Laptop batteries can be purchased cheap on Ebay and some other stores local to your area, this will now solve the problem of hard to find 18650's. :D I have pics of the batteries I got from my battery pack and from the store, but I am having problems posting them due to size limitations. All you have to do to harvest the batteries is pop the case open on the pack, and un attach the wires/soldering from the battery cells. These can be charged in any 18650 charger. I have noticed that a lot of the ones I got are Japanese made cells, Here is a SN/PN for one that came from a battery pack : CGR18650 CE, MH12210. I now have 20 of these 18650 batteries. Also these batteries are the UNPROTECTED type. I tested the voltage on the ones that were already re-charged and they were putting out 4.2V. The uncharged ones were putting out 3.5-3.8V. The only thing I am not sure of is the Mah rating of these harvested cells... I need to do some testing here. I hope this find will help out some members or anyone that may need this info.

Hope this helps/ed

Nathan
 





daguin

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Mar 29, 2008
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These are usually lower mAh batteries. They are fine for lower current applications (<500mA). However, once you start trying to pull >500mA from them, they are often not up to the task.

I am not saying don't use them. I am saying, that especially for the higher current applications we are seeing with the 445nm diodes and with higher powered DPSS lasers, they will quite often not be good enough.

Buy and use quality batteries

Peace,
dave

**EDIT** -- Oh yeah -- AND we have a board specifically set up for drivers and batteries (etc.)

Moving this now
 
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Ok, I didn't know they had lower Mah ratings. I do apologize for posting this in the wrong area, I was not sure where to post this. Thanks Dave. Hmm I guess the only way to get the high current 18650's is through the internet.... I can't find any locally here. I guess though if you look at the output sticker on the Laptop battery pack, is it possible to divide the current supplied by how ever many cells that are in the laptop pack and that would give an estimate of current output capability? Or does this differ cell to cell? I hate to give bunk/bum info out.**** UPDATE I have found a simple way to identify what the Mah ratings are for these harvested cells, the ring on the top of the cells (Japanese made only) are color coded as follows : Orange Color = 2200 mAh cell, Green Color = 2400 mAh cell , Light Blue Color = 2600 mAh cell. Cells that start with CGRxxxxxx are Panasonic Brand OEM cells. LGxxxx18650 are LG OEM Cells, of which the lowest rated I have found is 2200 mAh. Information about alot of these cells can be found HERE
 
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daguin

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Ok, I didn't know they had lower Mah ratings. I do apologize for posting this in the wrong area, I was not sure where to post this. Thanks Dave. Hmm I guess the only way to get the high current 18650's is through the internet.... I can't find any locally here. I guess though if you look at the output sticker on the Laptop battery pack, is it possible to divide the current supplied by how ever many cells that are in the laptop pack and that would give an estimate of current output capability? Or does this differ cell to cell? I hate to give bunk/bum info out.

Unfortunately, the mAh rating is not the only factor. Different cells can produce different current output under load as well. A 3000mAh rated cell may actually produce less current under load than a 1300mAh rated cell. Finally, if the cell is has a protection circuit, that circuit can sometimes limit the current load too.

I once tested a green for a man who was using cells from a laptop battery. The laser was producing ~250mW with his batteries (he sent several). This was under the spec of the laser. That is one reason why he sent it to me. When I popped an AW cell into the laser, it produced just under 400mW!

The battery CAN make a difference :evil:

Once again, you can certainly use the laptop batteries. Just don't expect too much of them ;)

Peace,
dave
 
Joined
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Nathan;

I have used hundreds of 18650 batteries in UV lights i have built.

Several additional factors with lithium-ion batteries determine the capacity that the cell can deliver.

1. Age of the cell since manufacture date.
Most Lithium-ion batteries have a 5-year life from date of manufacture.
The 3 yr. old cells you have have ~40% life left

2. Number of charging cycles the cells have been thru.
About 300 cycles is the typical life in a notebook battery.

3. The newer higher-capacity batteries have improved safety factors,
and some have been thru U.L. testing.

You got a quality manufactuer, but not all cells are "name-brand".

You can certainly use them, but they will have lost a good % of their original capacity.

I agree with Dave:
Buy and use quality batteries

LarryDFW

P.S. The reason the 18650 cells perform so well,
is due to their widespread use in notebook batteries.
 
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I did the same thing a while ago. I got 4 laptop batteries for free, tore them apart, and ended up with about 46 18650s n 10440s. They weren't changed at all, i had to make a adapter from my charging battery to the non-charging battery for it to even charge because the charger wouldn't notice it.

How long does it usually take these batteries to fully charge?
 
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I was meaning, if you go buy a NEW laptop battery pack and pull the cells out, you can get them locally that way, I have looked all over for 18650's is stores and there just are not any. There are many stores that sell laptop batteries brand new for $65-$99, and if you do the math on that, 6-8 cells, thats anywhere from $8- $12.50 a piece for each cell. I noticed that there is/are some concern for low mAh ratings, all of the cells I looked up and checked the part numbers on ranged from 2200 mAh to 2600 mAh. They could be rated at that mAh level but only put out half that, but a lot of the LG and Japanese made cells have a max discharge current of 5.0A, and are sold on a lot of other web pages, Amazon.com included, and the LG cells go for about 8 bucks on there. I am still going to just go buy a four pack of Tenergy 2600mAh batteries and call it a day, they are $28.00 on Amazon for the 4 pack. I know the ones I got from the old laptop batteries were not that good, as they usually only get about 4.15-4.18 v out of a full charge. I have noticed that these cells usually take many hours to charge 8-16 hrs with my trust fire multi cell charger.
 
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laptop 18650 are generally great. Only problem is that they aren't brand new.

I have some panasonics that I pulled from a laptop, spec'd at max. 4A continuous discharge. That's generally the starting point for a large-capacity name-brand cell, 2*C, or 2 times the value of the capacity.

Where you get more performance from buying cells from Larry or AW is from knowing that not only are they quality cells, but they're brand new.
 
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They could be rated at that mAh level but only put out half that, but a lot of the LG and Japanese made cells have a max discharge current of 5.0A, and are sold on a lot of other web pages, Amazon.com included, and the LG cells go for about 8 bucks on there. I am still going to just go buy a four pack of Tenergy 2600mAh batteries and call it a day, they are $28.00 on Amazon for the 4 pack.

LG is a "name brand" cell.

It will be much more reliable than the Tenergy cells.

The Sanyo 2400mah cells I have are $7.95 ea. prepaid.

Larry
 
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Hello all,

Apparently inside every laptop battery pack there are 4-6 18650's inside each pack!!!!!

my 2 battery packs i harvested a few months ago had 12 each :D they were for dell laptops, appear to be 2300mah after much testing, but max out as daguin said above at around 500ma
 




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