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  1. #26
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    Here are the batteries.

    2pcs Panasonic 18650 NCR18650B 3400mAh Rechargeable battery Free Shipping | eBay

    Charging voltage 4.2v
    Nominal voltage 3.6v
    Cut-off voltage 2.5v
    Capacity (0.2C, 2.5v discharge) 3400maH

  2. #27
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    I bought hundred oem NCR18650A from taobao 6.64$ incl ship, and created ebike battery.
    So DX is reseller.



    Sorry, bad english.
    10.0kg custom.

  3. #28
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    Quote Originally Posted by Ofroad'bent View Post
    I got some of the unprotected 3400maH Panasonics.
    I tried them in a friend's protected 1S2p holder, but couldn't get more than 2500 maH out of them.
    I suspect it's something to do with a crummy PCM in the holder.

    I got 2550 out of one cell tested directly without PCM. Still not what I expected.
    My Accucell charger was set to discharge them to 3.0v.

    I seem to remember reading that these cells have more capacity down to lower voltages without damage. Maybe I should have tested them to lower voltage.

    This will be a PITA if I have to reconfigure my lights voltage cut-off, and suspect the PCMs I ordered from ktronic will cut off at 3v anyway.

    Any thoughts?
    what was your discharge rate?
    are you expecting too much?
    ...Scun.thorpe, UK

  4. #29
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    Discharge at 1A.
    I was expecting 6800 maH, not 2500 from 1S2P

  5. #30
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    Quote Originally Posted by Ofroad'bent View Post

    I got 2550 out of one cell tested directly without PCM. Still not what I expected.
    My Accucell charger was set to discharge them to 3.0v.

    Any thoughts?
    ahh not so good then, ...but this statement threw me ^
    ...Scun.thorpe, UK

  6. #31
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    I just got battery tabs welded onto my DX protected 3100 Pannys yesterday - I've got the 1st one running through a discharge/recharge cycle on my Accucell-6 now. I'll post my results.

    Anyone know a way to get the Accucell to discharge to less than 3.0v/cell? Not that I'd really want to on a regular basis.

  7. #32
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    set it to Pb or ni-MH and adjust the cut off
    ...Scun.thorpe, UK

  8. #33
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    sorry to hear about that ofroad. So was the 2500mAh per cell or per 1S2P pack? First is a rewrapped cell (Sanyo 2600?), second is complete junk.

    There's not really much point discharging below 3V as there's next to know capacity left below there (about 10% left under 3.2V @ <0.5C discharge).

    Other than Orbtronic (US based business that also sells on eBay), I really really REALLY would advise against buying 18650 cells off eBay, even more so from China. There are so many other options, that it's just not worth the waste of time, even if you get your money back from Paypal.

  9. #34
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    Quote Originally Posted by iperov View Post
    I bought hundred oem NCR18650A from taobao 6.64$ incl ship, and created ebike battery.
    that's a truly insane amount of battery soldering! It would almost be worth buying a battery spot welding set up for doing that many

  10. #35
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    As suspected, there was a problem with the Protected holder. Just found that one side of the holder is bad, so only 1 cell was running. Still low capacity for even one cell.

    The cells sure look like genuine Panasonic 18650bs.
    Should have taken Matt's advice.

  11. #36
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    Quote Originally Posted by mattthemuppet View Post
    that's a truly insane amount of battery soldering! It would almost be worth buying a battery spot welding set up for doing that many
    I bought new 255 pcs from taobao by $3.3 each + taobao agent % + about $100 shipping
    this will really insane xD I planning 48V 40ah ebike battery weighting 8-9kg.
    Sorry, bad english.
    10.0kg custom.

  12. #37
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    Quote Originally Posted by Ofroad'bent View Post
    As suspected, there was a problem with the Protected holder. Just found that one side of the holder is bad, so only 1 cell was running. Still low capacity for even one cell.

    The cells sure look like genuine Panasonic 18650bs.
    Should have taken Matt's advice.
    Out of curiosity, do the labels have any overprinting like you see on the (-) end of the picture at the top of this review: Test / Review: Panasonic NCR18650B 3400mAh (Green) | BudgetLightForum.com ?

    Part of the reason I ask is that there are fake wrappers available on taobao for what seems like every brand of battery (including some panasonics, though I haven't seen the 3400s).
    The study du jour: can one's reputation be artificially inflated by simply putting a request for rep in one's sig?

  13. #38
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    We all know the old addage of if it looks too good to be true it probably is .

    has any one tried weighing cells and comparing them to lesser AH cells
    I did with some 14.8 volt 4.4 packs and a 5.2ah pack because I had plastidipped them all and forgot to mark the 5.2 pack

    it was heavier than the 4.4s

    I ahve it from Smudge who makes his living from batteries that the 3.4 ah cells are a rarity
    and unreliable so he rarly specs them in stuff.

  14. #39
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    Quote Originally Posted by borrower View Post
    Out of curiosity, do the labels have any overprinting like you see on the (-) end of the picture at the top of this review: Test / Review: Panasonic NCR18650B 3400mAh (Green) | BudgetLightForum.com ?

    Part of the reason I ask is that there are fake wrappers available on taobao for what seems like every brand of battery (including some panasonics, though I haven't seen the 3400s).
    Yes, there is the overprinting. Does that imply fake or genuine?

  15. #40
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    Quote Originally Posted by mattthemuppet View Post
    personally I wouldn't touch 'em with a pole, especially that that price. It doesn't matter what they say about the PCB, there's no guarantee that it will actually be that (or even a real PCB, believe it or not). Plus they don't specify the overcurrent spec or anything like that. eBay + 18650 + China = bad.

    I would trust Orbtronic (or it's eBay shop) or CNqualitygoods. I've bought and tested batteries from both places. Plenty of people have had successful orders with KumaBear on BLF too. Prices seem pretty reasonable - $12.50 for protected and $10.50 for unprotected NCR18650B. I'd be more likely to trust some random person off BLF than I would a Chinese eBay seller
    Guess I'll return the wimpy cells. Orbtronic and Kumabear don't ship outside US. Is CNquality kosher?

  16. #41
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    Quote Originally Posted by Ofroad'bent View Post
    Yes, there is the overprinting. Does that imply fake or genuine?
    I've got no expertise here, but I'd imagine that the overprinting is a good sign... though I suppose it's possible that if it was a fake label, they could have added in the appearance of overprinting.
    The study du jour: can one's reputation be artificially inflated by simply putting a request for rep in one's sig?

  17. #42
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    Quote Originally Posted by Ofroad'bent View Post
    Guess I'll return the wimpy cells. Orbtronic and Kumabear don't ship outside US. Is CNquality kosher?
    the one cell (NCR18650) I got from them was legit, although that doesn't say anything about any other models. Their CS is kinda crappy though - Intl.Outdoor is better and the owner does a mahoosive amount of battery tests on BLF.

  18. #43
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    Quote Originally Posted by mattthemuppet View Post
    the one cell (NCR18650) I got from them was legit, although that doesn't say anything about any other models. Their CS is kinda crappy though - Intl.Outdoor is better and the owner does a mahoosive amount of battery tests on BLF.
    Link to Intn'l Outdoor please?

  19. #44
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    Quote Originally Posted by Ofroad'bent View Post
    Link to Intn'l Outdoor please?
    Google is your friend: Led Flashlight-International Outdoor Store

  20. #45
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    Quote Originally Posted by mattthemuppet View Post
    the one cell (NCR18650) I got from them was legit, although that doesn't say anything about any other models. Their CS is kinda crappy though - Intl.Outdoor is better and the owner does a mahoosive amount of battery tests on BLF.
    OK, ordered a pair of protected 3400s from Intl Outdoor.
    When I get them I'll test 'em and report back.
    Last edited by Ofroad'bent; 01-14-2013 at 07:18 AM.

  21. #46
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    FYI - and I don't know enough to be dangerous, but checking the review of the protected DX3100's on BLF : Test / Review: NCR18650A protected (Green) | BudgetLightForum.com

    I discharged my cells down to 3v and recharged getting 2734 and 2831ma out of each cell I charged yesterday. That approximates the graph of testing on BLF, so I'm fairly certain I got what I paid for. I ordered and received mine from DX right before Christmas.

    The local BatteriesPlus welded tabs on to all 4 of mine for no charge (they even used thier own tabs!) - I was surprised, as I'm not a regular customer there. I might have to talk to them next time I buy cells though, as the guy behind the counter says he can get 18650's like those. We didn't discuss price. I was impressed at the local franchise's customer service, and I'll go back there for other stuff.

  22. #47
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    Quote Originally Posted by adrenalnjunky View Post
    FYI - and I don't know enough to be dangerous, but checking the review of the protected DX3100's on BLF : Test / Review: NCR18650A protected (Green) | BudgetLightForum.com

    I discharged my cells down to 3v and recharged getting 2734 and 2831ma out of each cell I charged yesterday. That approximates the graph of testing on BLF, so I'm fairly certain I got what I paid for. I ordered and received mine from DX right before Christmas.
    Well, mine weren't a ton lower, but should have been in the 3200 range, not 2550.

  23. #48
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    Oh yeah - I agree that something's up on yours. sounds more like you've got 2700-2900mah cells. If you can't return them - I'd personally pull the wrappers on one just to see if you can find any other markings.

    Is it possible there's a really high amount of resistance in the internal wiring of the holders being used that might be causing the sensing in your charger some grief? I'm just thinking out loud here.

  24. #49
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    Quote Originally Posted by adrenalnjunky View Post
    Oh yeah - I agree that something's up on yours. sounds more like you've got 2700-2900mah cells. If you can't return them - I'd personally pull the wrappers on one just to see if you can find any other markings.

    Is it possible there's a really high amount of resistance in the internal wiring of the holders being used that might be causing the sensing in your charger some grief? I'm just thinking out loud here.
    Nah, I tested some unprotected Digikey holders too.

  25. #50
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    Well, the good news is I just got a full refund from the vendor on eBay. Didn't even ask me to return the cells yet. He still claims they are genuine, and perhaps my testing isn't accurate. He feels they'll run longer in the lights, but was good enough to refund so I have no complaints.

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