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  1. #1
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    The battle of the 7.4v battery packs (2cell vs. 4cell vs. 2x "long C")

    I was a little dissapointed in the 2x 18650 pack on my Quazzle triple. I built a 4x 18650, but it's just so freakin' big compared to the light, hahaha.

    I split the difference between the 2500mAh pack and the 5000mAh pack and ordered a pair of 26650 4000mAh's with a PCM. It should give me the run time I desire with a slightly smaller size than the 4cell pack.

    If my own personal light was going to be a bar mount...I wouldn't care a bit, but I like to have a helmet mount light with the battery pack on the helmet itself instead of a wire running to my hydration pack.


    I will report with run times of all 3 packs when done.


    So far...the 2cell 18650 pack is 1hr 10min with a Lux-RC L33.2 at 1.1amps.

  2. #2
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    Quote Originally Posted by chelboed
    I was a little dissapointed in the 2x 18650 pack on my Quazzle triple. I built a 4x 18650, but it's just so freakin' big compared to the light, hahaha.

    I split the difference between the 2500mAh pack and the 5000mAh pack and ordered a pair of 26650 4000mAh's with a PCM. It should give me the run time I desire with a slightly smaller size than the 4cell pack.

    If my own personal light was going to be a bar mount...I wouldn't care a bit, but I like to have a helmet mount light with the battery pack on the helmet itself instead of a wire running to my hydration pack.


    I will report with run times of all 3 packs when done.


    So far...the 2cell 18650 pack is 1hr 10min with a Lux-RC L33.2 at 1.1amps.

    My helmet lights (similar internals to the CuLite link below) are a single XP-G driven at 1A and output around 350 lumens. A single 18650 helmet mounted will run for 2 hrs 15 mins.

  3. #3
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    First test on the 4cell pack tonight yields 2hrs 43min on the triple XP-G at 1.1amps. 2x the pack gave 2.33x runtime. Voltage sag is my assumption for the poor performance of the 2cell pack. All six of these 18650's were purchased at the same time and charged approx the same amount of times. (maybe 3-5 times)

    2cell 2500mAh pack - 1hr 10min
    4cell 5000mAh pack - 2hrs 43min

    2x 26650's with PCM OTW...will report back. I'm hoping to get a good strong 2hrs from the fatty pack. Should be a good comprimise between size and capacity.

  4. #4
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    Quote Originally Posted by OverTheHill
    My helmet lights (similar internals to the CuLite link below) are a single XP-G driven at 1A and output around 350 lumens. A single 18650 helmet mounted will run for 2 hrs 15 mins.
    Not to disagree with you, but I've had DX drivers that only deliver 1/2 the claimed current. Have you checked it with a meter to assure a full 1000mA? If so...then that's exceptional!

  5. #5
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    Quote Originally Posted by chelboed
    Not to disagree with you, but I've had DX drivers that only deliver 1/2 the claimed current. Have you checked it with a meter to assure a full 1000mA? If so...then that's exceptional!
    No, I haven't measured the current output from these drivers but I have built several lights using them now and haven't noticed any difference in the brightness levels so either they're all faulty (to approximately the same level ) or none of them are. I will try and measure the next one I build though for my own education.

    I hope you get your battery problem sorted to your own satisfaction.

  6. #6
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    my 2 cents: http://www.lux-rc.com/view.php?p=con...L332_run_times

    I used a custom 2S 2200mah battery (3.5oz):


    The battery was checked and charged:


    the run-time is 1 hour and 43 minutes. As expected.

  7. #7
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    That's good to know...but really odd. LiPo's work better in this application than LiIon, maybe?

    A little birdy told me that LiIon would be better w/ LiPo's doing better on R/C. I'll have to try one.
    Last edited by chelboed; 06-07-2010 at 06:41 AM.

  8. #8
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    Quote Originally Posted by chelboed
    That's good to know...but really odd. LiPo's work better in this application than LiIon, maybe?

    A little birdy told me that LiIon would be better w/ LiPo's doing better on R/C. I'll have to try one.
    no, completely wrong. How did you measure the actual capacity of your 2S setup? I have strong doubts that they're still 2500.

    LiPo cells vary depending on rated discharge/charge current, operational temp.range, internal resistance and so on. For portable lighting I picked up 2C discharge cells which used for mobile devices, not for R/C. They provide wider temp. range and more compact than "classic" high-discharge LiPo cells.

  9. #9
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    Purely mfgr rating. Where can I find some similar to those?

  10. #10
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    i can provide you with a sample next time. I plan to supply them too in the future

  11. #11
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    Excellent.

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    Got these two LiMnNi's in. Sizewise...they'll fit between a 4cell and 2cell 18650...but at 4000mAh.


    I'm almost not even excited about them anymore though due to quazzle's lipo offer


  13. #13
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    I've spent a lot of time searching the net for info on Li-po cells, and the general opinion seems to be that they pose significantly higher risk of burning your house down than Li-ion. Obviously I'm keen for a super trick set-up, but I also want to be able to come home from my regular Wednesday night ride, plug in my battery, and forget about it until next Wednesday night when I go riding again. I was going to order some Magic-Shine spares off e-bay for my power requirements. Am I wrong?

    b.
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  14. #14
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    Quote Originally Posted by bshallard
    I've spent a lot of time searching the net for info on Li-po cells, and the general opinion seems to be that they pose significantly higher risk of burning your house down than Li-ion. Obviously I'm keen for a super trick set-up, but I also want to be able to come home from my regular Wednesday night ride, plug in my battery, and forget about it until next Wednesday night when I go riding again. I was going to order some Magic-Shine spares off e-bay for my power requirements. Am I wrong?

    b.
    No, you're not wrong. There are a number reasons Li-ion cells are safer than lipo cells. First, the metal shell of a li-ion cell makes them more resistant to physical abuse and damage. Second, li-ion cells have an internal mechanical pressure based safety cutoff switch. If the pressure inside the cell gets too high, it opens the electrical path to stop any charge or discharge current. Lipo cells do not have an internal pressure switch.

    The third reason is more a common practice than an inherent advantage of one type over the other. Most Li-ion pack are built with an electronic protection PCB. Most Lipo pack are not built with an electronic protection PCB. But, there's no technical reason you can't add a protection PCB to a lipo pack.

    Lipo packs are really the only choice in high current applications like RC models. For low current applications like bike lights, li-ion packs are usually the better choice. But, keep in mind that there is a huge variance in quality of li-ion cells. Don't expect to get very good cells from cheap chinese mail order places. Most of those cells won't have the stated capacity and they don't handle higher currents very well. If you compare those to Sanyo cells for example, the difference is pretty dramatic. Real "LG" cells are pretty good too, but I've seen some people do try to pass off cheap chinese cells as "LG".

    From the testing I've done, the Magicshine packs are descent, but I can't vouch how they'll hold up over 3-4 years.

  15. #15
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    There was a TKMonster on CPF that exploded, took out a sliding glass door, imbedded rocks into the adjacent sheetrock wall, took out a complete glass barrier, and shot the light across a parkinglot and landed on top of a garage...taking out a skylight. Had the light some sort of gas vent...it would have prob. just gone up in flames, but the lack of venting turned it into an explosive device.

    It had those green 18650's in it. Arent they Sanyo's?


    Edit: Nevermind...Sony's.

    http://www.candlepowerforums.com/vb/...d.php?t=262234
    Last edited by chelboed; 06-13-2010 at 08:12 PM.

  16. #16
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    I sold the square triple that I was testing pack on...so this test will be somewhat delayed until I get my next Lux-rc boards...hopefully order this week.

    For what it's worth...I ran the single XP-G micro light on this new "long-C" pack and it ran 8hrs before I got bored and shut it down.

  17. #17
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    Quote Originally Posted by MtbMacgyver
    No, you're not wrong. There are a number reasons Li-ion cells are safer than lipo cells. First, the metal shell of a li-ion cell makes them more resistant to physical abuse and damage. Second, li-ion cells have an internal mechanical pressure based safety cutoff switch. If the pressure inside the cell gets too high, it opens the electrical path to stop any charge or discharge current. Lipo cells do not have an internal pressure switch.

    The third reason is more a common practice than an inherent advantage of one type over the other. Most Li-ion pack are built with an electronic protection PCB. Most Lipo pack are not built with an electronic protection PCB. But, there's no technical reason you can't add a protection PCB to a lipo pack.

    Lipo packs are really the only choice in high current applications like RC models. For low current applications like bike lights, li-ion packs are usually the better choice. But, keep in mind that there is a huge variance in quality of li-ion cells. Don't expect to get very good cells from cheap chinese mail order places. Most of those cells won't have the stated capacity and they don't handle higher currents very well. If you compare those to Sanyo cells for example, the difference is pretty dramatic. Real "LG" cells are pretty good too, but I've seen some people do try to pass off cheap chinese cells as "LG".

    From the testing I've done, the Magicshine packs are descent, but I can't vouch how they'll hold up over 3-4 years.

    Should have written this a couple of days ago.
    Thanks Macgyver. That was a very comprehensive answer. I want a pack that I don't have to pull the individual cells out of for charging, so the MagicShine pack and charger combo should fit the bill nicely. If I have to replace the cells in a couple of years then I can live with that. I managed to get in early with Serge aka Quazzle, so a number of 332 boards and optics should be on their way to me soon. I spent last night redesigning my 332 housing for a slimmer appearance, ordered some inch diameter alloy today, and should fire up the lathe again on Saturday. Good thing too. I'm getting sick of being under-lit on my Wednesday night group rides.

    Ole.
    b.
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  18. #18
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    Quote Originally Posted by MtbMacgyver
    No, you're not wrong. There are a number reasons Li-ion cells are safer than lipo cells. First, the metal shell of a li-ion cell makes them more resistant to physical abuse and damage. Second, li-ion cells have an internal mechanical pressure based safety cutoff switch. If the pressure inside the cell gets too high, it opens the electrical path to stop any charge or discharge current. Lipo cells do not have an internal pressure switch.

    The third reason is more a common practice than an inherent advantage of one type over the other. Most Li-ion pack are built with an electronic protection PCB. Most Lipo pack are not built with an electronic protection PCB. But, there's no technical reason you can't add a protection PCB to a lipo pack.

    Lipo packs are really the only choice in high current applications like RC models. For low current applications like bike lights, li-ion packs are usually the better choice. But, keep in mind that there is a huge variance in quality of li-ion cells. Don't expect to get very good cells from cheap chinese mail order places. Most of those cells won't have the stated capacity and they don't handle higher currents very well. If you compare those to Sanyo cells for example, the difference is pretty dramatic. Real "LG" cells are pretty good too, but I've seen some people do try to pass off cheap chinese cells as "LG".

    From the testing I've done, the Magicshine packs are descent, but I can't vouch how they'll hold up over 3-4 years.
    Agree in general. With mine 2 cents.

    I have picked up LiPo for my project because low-current LiPo elements provide higher Capacity-to-weight ratio and with these cells a better usage of the unit internal area is possible. They occupy 99% of the inside volume becase of their almost ideal "parallelogramical" shape. With standard LiIon cylinders you waste volume between them when packed to a rectangular case.

    Of course extra efforts needed to protect bare LiPos electrically and physically. That's why I pack them into a metall & carbon heavy duty leakproof housing with a complicated microcontroller-based monitor curcuit with over-current, low-voltage, ballance and temp. control


  19. #19
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    Quote Originally Posted by quazzle
    Agree in general. With mine 2 cents.

    I have picked up LiPo for my project because low-current LiPo elements provide higher Capacity-to-weight ratio and with these cells a better usage of the unit internal area is possible. They occupy 99% of the inside volume becase of their almost ideal "parallelogramical" shape. With standard LiIon cylinders you waste volume between them when packed to a rectangular case.

    Of course extra efforts needed to protect bare LiPos electrically and physically. That's why I pack them into a metall & carbon heavy duty leakproof housing with a complicated microcontroller-based monitor curcuit with over-current, low-voltage, ballance and temp. control
    This isn't possible for the average DIY'r. The minor tradeoff of wasted volume is well worth not having to make a housing to protect the cells. Also, IMO adding a protective housing would lessen the weight advantages of LiPo cells.

  20. #20
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    Then there is the issue of catastrophic failure of the battery pack in an enclosed metal/carbon container.

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    The container is nice...and I think that if you either cushion the pack inside or make it fit really snug...you prob. wouldn't have an issue with

    I wonder if a few dips in PlastiDip would be enough protection? That stuff is rather stout.



    But...the added container + cushion= possibly same size as the LiIon counterpart maybe? Dunno. I'm still going to try some LiPo's to see what all the hubub is about. They sure are compact.

    Quazzle...do you have a pic of your container compared to some sort of common object for size comparison?

  22. #22
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    I just plasti-dip all my packs. Waterproof and takes general abuse well.
    Works fine other than wrecking badly slamming the packs into trees, rocks, spokes, etc.

    You could easily incorporate those fancy ridges onto collars and place collars on the battery pack then plasti-dip the whole thing.

  23. #23
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    Quote Originally Posted by chelboed
    First test on the 4cell pack tonight yields 2hrs 43min on the triple XP-G at 1.1amps. 2x the pack gave 2.33x runtime. Voltage sag is my assumption for the poor performance of the 2cell pack. All six of these 18650's were purchased at the same time and charged approx the same amount of times. (maybe 3-5 times)

    2cell 2500mAh pack - 1hr 10min
    4cell 5000mAh pack - 2hrs 43min

    2x 26650's with PCM OTW...will report back. I'm hoping to get a good strong 2hrs from the fatty pack. Should be a good comprimise between size and capacity.

    Well...I finally got another triple cobbled together so I could test this 2s/1p long C pack.

    2s/1p 18650 Trustfire "2400mAh" pack - 1hr 10min
    2s/2p 18650 Trustfire "5000mAh" pack - 2hrs 43min
    2s/1p 26650 IMR 4000mAh pack - 2hrs 44min



    The conclusion:
    The 2x Long-C cells are physically about 1/2 way between the 2cell and 4cell 18650 packs with regards to physical size and bulk. But...I get the same runtime as I do with the 4cell pack.



    I'm very, very happy with these results.

  24. #24
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    Quazzle, that computerized hook-up display showing a monitored output....Absolutely awesome...Kudos...

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