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Re: [time-nuts] Li-ion Battreries

E
EWKehren@aol.com
Sun, Jan 22, 2017 7:59 PM

The reason I made the post is after bad experiences I found a vendor with
genuine product and willingness to send you data sheets and my tests confirm
data within 3%. Can not ask for more. Can tell all the stories mentioned,
been  there done it, that is why I felt it will be useful for time nuts.
The Samsung data sheet is 752K otherwise I would attach. Claim 3350mA and
100% at 0.2C that is what I tested and got 3327mA well with inn my test
setup.

Bert Kehren

In a message dated 1/22/2017 12:45:41 P.M. Eastern Standard Time,
holrum@hotmail.com writes:

I have a  LOT of experience in testing and using 18650 cells.  It is a
horrible place for the un-initiated to be.  The market is so saturated  with
dangerous fakes and inferior, over-speced cells that finding a genuine  cell
is a vanishingly small probability.  Hopefully the seller mentioned  before
pans out and sticks around.

You can be pretty much assured that  any no-name Chinese cell will be
dangerous crap.  Buy a 3000 mAh  cell that is really 500 mAh and charge it at
the 3000 mAh 1C rate and  KERBLOOIE!  If you want to buy decent cells from a
reputable maker  (Samsung, Sony, Panasonic, etc) you have to be certified
that you know how to  properly build with and use them...  and also the
minimum order quantity  can be over 100,000 pieces.

Shop around and you can find sellers of  18650 shrink wrap sleeves for all
the major/reputable cells.  I  have yet to test a Chinese cell that comes
even close to its advertised specs.  Also probably 90+% of what is offered as
genuine name brand cells are  fakes.

Your best bet for finding a decent cell is to get them from  GENUINE laptop
packs.  That is easier said than done...  counterfeit  packs are the norm.
Also, most newer laptops use packs with pouch  cells.  18650's are on the
way out for modern  machines.


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The reason I made the post is after bad experiences I found a vendor with genuine product and willingness to send you data sheets and my tests confirm data within 3%. Can not ask for more. Can tell all the stories mentioned, been there done it, that is why I felt it will be useful for time nuts. The Samsung data sheet is 752K otherwise I would attach. Claim 3350mA and 100% at 0.2C that is what I tested and got 3327mA well with inn my test setup. Bert Kehren In a message dated 1/22/2017 12:45:41 P.M. Eastern Standard Time, holrum@hotmail.com writes: I have a LOT of experience in testing and using 18650 cells. It is a horrible place for the un-initiated to be. The market is so saturated with dangerous fakes and inferior, over-speced cells that finding a genuine cell is a vanishingly small probability. Hopefully the seller mentioned before pans out and sticks around. You can be pretty much assured that any no-name Chinese cell will be dangerous crap. Buy a 3000 mAh cell that is really 500 mAh and charge it at the 3000 mAh 1C rate and KERBLOOIE! If you want to buy decent cells from a reputable maker (Samsung, Sony, Panasonic, etc) you have to be certified that you know how to properly build with and use them... and also the minimum order quantity can be over 100,000 pieces. Shop around and you can find sellers of 18650 shrink wrap sleeves for all the major/reputable cells. I have yet to test a Chinese cell that comes even close to its advertised specs. Also probably 90+% of what is offered as genuine name brand cells are fakes. Your best bet for finding a decent cell is to get them from GENUINE laptop packs. That is easier said than done... counterfeit packs are the norm. Also, most newer laptops use packs with pouch cells. 18650's are on the way out for modern machines. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.