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  1. #26
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    Quote Originally Posted by LeeG View Post
    aren't there higher capacity Nimh C size batteries out there?

    here they are 6000mah that's more than the typical 2650mah AA battery

    here's a case to put them in

    http://www.allelectronics.com/make-a...-CELLS//1.html


    http://www.onlybatteries.com/cat_fea...d=112&uid=1015
    There's been a lot of interesting replies.

    Quoting me saying that I already have a case, the problem was the cost of "real" C size batteries, then giving me a link to "C" size cases - not very interesting. Or useful.

    The problem with the C or D batteries, as I mentioned, isn't one of availability it's one of cost. 4 real C cells cost around $40, 4 D cells $50-$60. Then you might have to buy the case. Then you have to buy the charger, because your standard charger nowadays typically only handles AA and AAA. By that point, you've spent the same money for a battery system that's larger, heavier, and far more annoying to charge than if you just bought the lith-ion version in the first place. Even replacement cost, once they run out, is the same.

    P.S. Now I fully expect someone will post a link to the fake (same capacity in a wrapper shell) C or D cells and say that I was wrong about the cost...

  2. #27
    Seņior Member ItsJustMe's Avatar
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    Quote Originally Posted by PaulRivers View Post
    P.S. Now I fully expect someone will post a link to the fake (same capacity in a wrapper shell) C or D cells and say that I was wrong about the cost...
    Well, not quite.
    http://www.batteryspace.com/nimhrech...tontop1pc.aspx

    These are real D cells, $6.45 each, so $26 for a pack.

    The charger is an issue though, especially if you already have a charger. These cells should probably be charged at about 5 amps or so, and if you do 4 at a time that's delivering 20 amps to the cells. That's a big, expensive charger. Most that you're likely to get for a reasonable price might charge at 0.75 to 1 amp per cell, which means it's an overnight charge at best, and that slow of a charge probably isn't ideal for the cells.

    Yup, here's a suitable charger for $25; up to 10 hours to charge at 820 mA:
    http://www.batteryspace.com/bc1huuni...batteries.aspx

    I agree with you though; if you don't already have this stuff, I'd just go with the LiIon pack. If I were doing it again I'd go for a taillight option with LiIon, if I could find one for a reasonable price. The MagicShine would be good except it doesn't have the Dinotte flash patterns.
    Work: the 8 hours that separates bike rides.

  3. #28
    Senior Member Richard Cranium's Avatar
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    Well - you guys really hashed out about every angle for calling Dinotte dumb-trucks. My previous post tried to point there was more to Dinotte light heads than on/off and or power setting.

    And I still don't see a schematic of any of there products. One sort of "test" does come to mind regarding mixing battery sources and light heads. If a Dinotte light head displays the known "correct" self test flashes when hooking up a non-standard battery - I would go along with the idea that the light head circuits are robust enough to utilize a particular battery source a cyclist improvised. If it doesn't - then who knows?

    I just completed an "all night" bike ride and by using more than one light and battery source I never had to switch out a battery source so at this time I'm "dee-lighted."

  4. #29
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    Quote Originally Posted by ItsJustMe View Post
    Well, not quite.
    http://www.batteryspace.com/nimhrech...tontop1pc.aspx

    These are real D cells, $6.45 each, so $26 for a pack.

    The charger is an issue though, especially if you already have a charger. These cells should probably be charged at about 5 amps or so, and if you do 4 at a time that's delivering 20 amps to the cells. That's a big, expensive charger. Most that you're likely to get for a reasonable price might charge at 0.75 to 1 amp per cell, which means it's an overnight charge at best, and that slow of a charge probably isn't ideal for the cells.

    Yup, here's a suitable charger for $25; up to 10 hours to charge at 820 mA:
    http://www.batteryspace.com/bc1huuni...batteries.aspx

    I agree with you though; if you don't already have this stuff, I'd just go with the LiIon pack. If I were doing it again I'd go for a taillight option with LiIon, if I could find one for a reasonable price. The MagicShine would be good except it doesn't have the Dinotte flash patterns.
    LOL, well - that IS an interesting reply. :-D

    Do you have any idea if those batteries have the capacity they claim? I only ask because I *did* look for D's that had a decent capacity, but for example look here - all 2 "D" cell batteries, none under $20 (so $40 for four):
    http://www.thomasdistributing.com/sh...rsllit8gi3gna7

    Sounds like we agree for the most part on the lith-vs aa - even if the AA battery pack was designed to hold the batteries in tight, the lith-ion pack would still be much simpler to charge. There is one single thing I found the AA pack better at - it's smaller than even the smallest (2 cell ) lith-ion battery pack. When I bring along an extra light in case I end up after dark and a friend doesn't have a light (I always have my own good lights :-D), I can put the AA version of 200L in my under-seat back easily, the lith-ion version is bigger.

    Anyways...maybe going a little off-topic, sorry. :-)

  5. #30
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    Quote Originally Posted by PaulRivers View Post
    Anyways...maybe going a little off-topic, sorry. :-)
    No, not at all. All this information is helpful. I asked "one" question to start the thread, but there are many more questions behind that one so it's all good. I especially like hearing how others have come up with unique modifications, even if it's something "simple" like using a chunk of inner tube. That would hold the batteries in place and protect them from shorting to something.

    ItsJustMe addressed something that's always bothered me - can you hook up too big of a battery to something? By "big" I mean amperage, not overvoltage. I always wondered if a battery with three or four or 20X the capacity of the original source could somehow arc across the internal circuitry. On the one hand, I knew that you could take a 12V car tail light and connect it directly to your car battery and the light would work. But a standard incandescent bulb is not the same as a $200 device with a circuit board and delicate electronics inside. ItsJustMe says "No", a bigger battery won't damage the device. I don't know "why" that is exactly, but I'll worry less about that in the future...

  6. #31
    Seņior Member ItsJustMe's Avatar
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    In general the answer is "no, you can't blow something by hooking too many amps to it." It's not a rock-solid guarantee, because there might be some flashlight designs that don't have a regulator, and count on the fact that the specified battery can only deliver a current that the LED can take, and it'd blow up if you used a different battery.

    But in the general case, no. The AA NiMHs that the Dinottes take, for instance, could easily deliver 10 amps instantaneous, which would fry the thing. But circuitry in general only draws the current that it needs (what it's been designed to draw).
    Work: the 8 hours that separates bike rides.

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