Panasonic 3100 mAh on dx

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  • 01-15-2013
    rschultz101
    comment,...
    new cells need to be cycled , 2-3 up to 5 times to get full capacity
    clones, etc, HK, would skip it. they are good at making labels,...
    panas,
    high capacity ?! yes, it's exiting . heard, they loose about 200-300mah in less than 50 cycles.
    if you got room, (more weight), or need current, stick to 26650's
    MS charger, don't charge them fully, cheap charger 6-8% less charge
  • 01-16-2013
    MtbMacgyver
    Quote:

    Originally Posted by rschultz101 View Post
    comment,...
    new cells need to be cycled , 2-3 up to 5 times to get full capacity

    I see people say this fairly often, but it's counter to what I've read in the technical literature from li-ion battery manufacturers. The few times I've measured light runtime on the very first cycle after building a pack, I haven't seen any increase after 2-3 cycles. I'm curious where this recommendation originates? It is true for nickle based batteries.
  • 01-16-2013
    rschultz101
    usually on quality cells, cycling is part of conditioning and testing.
    cheaper mfg's skip on everything.
    these new type cells, contain Nickel.
    for packs, it is good to cycle / balance , measure, to ensure it's ok.

    Quote:

    Originally Posted by MtbMacgyver View Post
    I see people say this fairly often, but it's counter to what I've read in the technical literature from li-ion battery manufacturers. The few times I've measured light runtime on the very first cycle after building a pack, I haven't seen any increase after 2-3 cycles. I'm curious where this recommendation originates? It is true for nickle based batteries.

  • 01-16-2013
    MtbMacgyver
    Quote:

    Originally Posted by rschultz101 View Post
    usually on quality cells, cycling is part of conditioning and testing.
    cheaper mfg's skip on everything.
    these new type cells, contain Nickel.
    for packs, it is good to cycle / balance , measure, to ensure it's ok.

    Here's the official datasheet from Panasonic for this specific cell. The cycle number graph shows the capacity starting from 0 cycles with the highest capacity and falls after that.

    http://industrial.panasonic.com/www-...A4000CE254.pdf
  • 02-02-2013
    Ofroad'bent
    Quote:

    Originally Posted by Ofroad'bent View Post
    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.

    Finally got my PCMs from Kerry.
    The cells are testing 2600-2750 each, not bad but definitely short of the claimed 3400. No complaints with a full refund.

    The other hopefully more legit ones haven't arrived yet.
  • 02-02-2013
    borrower
    You'll get a different number, depending on the discharge rate... of course, the manufacturers make it an optimal one for their benefit. Plus, the 3400 is tested down to 2.5 volts IIRC, so you're losing some there.

    Last time I bought batteries, I figured that they were a bit better than 3100s for not much more coin, so went for it.
  • 02-04-2013
    mattthemuppet
    I doubt that you're losing much more that 5%, if that, by discharging down to 3V instead of 2.5V. HKJ did a bunch of tests for remaining capacity and found that there was only ~10% left below 3.2V. I've capacity tested NCR18650 and NCR18650A cells on my admittedly uncalibrated and probably not terribly accurate Thunder AC6 and they check out about right (2850 and 3050-3100, respectively). My guess is that the ones Ofroad'bent got were rewrapped Sanyos, which are still decent cells, just cheaper and lower capacity than NCR18650A/B.
  • 02-06-2013
    adrenalnjunky
    are those numbers after you add the 5 or 10% you mention, or those are the numbers you get when charging after a discharge down to 3v?
  • 02-06-2013
    mattthemuppet
    Quote:

    Originally Posted by adrenalnjunky View Post
    are those numbers after you add the 5 or 10% you mention, or those are the numbers you get when charging after a discharge down to 3v?

    the capacity figures are for a 1A discharge from 4.2V to 3V. If you want capacity down to 2.5V, add 5% at most to those figures. Don't forget though that this is with a hobby charger (ie. not calibrated) and for only 3 cells, so hardly what I'd call a scientific experiment :)