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Thread: New Cree headlight. Li-ion batteries problem.

  1. #1

    Default New Cree headlight. Li-ion batteries problem.

    Hi recently bought my wife a Cree headlight for her bike. It comes with a Li-ion battery x 4 pack. The batteries are shrink wrapped together in plastic with what looks like a fibrous cover plate at each end. A length of cable runs into one end of the pack. The other end of this cable has a plug and socket part which meets and connects to the headlight cable. Charging the battery with the included charger takes about 6-8 hours. Immediately after charging the batteries will run the light for at least ten hours. Trouble occurs when after charging, the batteries are not used for a day or two. Then the light will switch on for a couple of minutes before the batteries are completely flat. It's the same outcome whether the battery pack is connected to the light or not. Please can anyone tell me if this is likely to be a short circuit in the cabling, or due to defective batteries? Mike

  2. #2

    Default Re: New Cree headlight. Li-ion batteries problem.

    If there's no further description to the light than "CREE" (like saying you bought an OnSTAR car), then there's a good chance its an off-brand import that uses cheap or refurbished cells. Possibly one or more of the cells is weak/internally shorted, causing the other cells to rapidly discharge into it. If the battery pack could also have been dropped/heated/damaged/sitting on the shelf for 2 years between the time it was manufactured and when you acquired it. What brand/model is the light?
    If the battery pack is under any kind of warranty, you should be able to get a replacement. Otherwise, be prepared to pony up for a replacement pack or spend untold dollars and hours rebuilding the pack with well-matched replacement cells.

  3. #3

    Default Re: New Cree headlight. Li-ion batteries problem.

    Quote Originally Posted by A10K View Post
    If there's no further description to the light than "CREE" (like saying you bought an OnSTAR car), then there's a good chance its an off-brand import that uses cheap or refurbished cells.
    Thanks for the reply,
    I got the light on eBay from a Chinese seller. The light seems good quality "CREE XML-T6 Light".
    Here's a picture of the complete kit:

    [corrupted file: Image link contained ~35,000 characters. Deleted. - DM51]

    Possibly one or more of the cells is weak/internally shorted, causing the other cells to rapidly discharge into it. If the battery pack could also have been dropped/heated/damaged/sitting on the shelf for 2 years between the time it was manufactured and when you acquired it. What brand/model is the light?
    No info on the body of the light. Only the description shown above.

    If the battery pack is under any kind of warranty, you should be able to get a replacement. Otherwise, be prepared to pony up for a replacement pack or spend untold dollars and hours rebuilding the pack with well-matched replacement cells.
    If rebuilding the pack consists of purchasing a set of batteries, grouping them and making some fairly simple connections, I might just manage that. OTOH "untold dollars and hours" and "well matched" may imply a more complicated procedure that I'd be cautious to attempt.

    Is it likely I could pick up a ready made pack including the cable and plug to match the existing?

    The seller kindly offered a small refund to help cover the replacement cost.

    Mike
    Last edited by DM51; 02-28-2012 at 07:29 AM.

  4. #4
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    Default Re: New Cree headlight. Li-ion batteries problem.

    Quote Originally Posted by MickyLuv View Post
    Chinese seller... Here's a picture of the complete kit:

    [corrupted file: Image link contained ~35,000 characters. Deleted. - DM51]
    Welcome to CPF, Mike.

    The link to the pic you posted was colossal, and had obviously been corrupted somewhere along the line. It was around 35,000 characters long, occupying ~70 pages, lol.

    I suggest you delete it from your own computer to avoid possible problems with it.
    Last edited by DM51; 02-28-2012 at 07:31 AM.
    Resistance is futile...

  5. #5

    Default Re: New Cree headlight. Li-ion batteries problem.

    Quote Originally Posted by DM51 View Post
    Welcome to CPF, Mike.

    The link to the pic you posted was colossal, and had obviously been corrupted somewhere along the line. It was around 35,000 characters long, occupying ~70 pages, lol.

    I suggest you delete it from your own computer to avoid possible problems with it.
    Thanks for the welcome.
    I just dragged the JPG into the message window from the desktop. It looked OK but it may have been the wrong method.
    Does the image need to already be on a web server accessed using a URL?

    Mike

  6. #6
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    Default Re: New Cree headlight. Li-ion batteries problem.

    Quote Originally Posted by MickyLuv View Post
    Does the image need to already be on a web server accessed using a URL?

    Mike
    Yes. I suggest imgur.com as a free quick solution for this. Upload it and then bring the image here. You will need to use BBcode image tags:
    Code:
    [img]URL to Image.jpg[/img]
    My biggest light-hog is my camera.

  7. #7
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    Default Re: New Cree headlight. Li-ion batteries problem.

    Something obviously went wrong with that drag-and-drop, lol. It's not the right way to do it here, anyway.

    Photos need to be hosted on a recognised hosting service, such as Photobucket, Google Picasa, Flickr, etc.

    Hotlinking pics direct from someone else's website isn't allowed, as it is stealing their bandwidth. Quite often, we find hotlinked images have been deleted from the original site and no longer exist, or have even been changed to something wholly unsuitable, lol.

    There are 3 threads here that show you how to do it properly: Posting photos.


    Edit: ^ Mr. Snail was quicker than me!
    Last edited by DM51; 02-28-2012 at 08:06 AM.
    Resistance is futile...

  8. #8

    Default Re: New Cree headlight. Li-ion batteries problem.

    Thanks all for your patience and advice.

    I took the photo myself this morning so it's not got any alien connections. :-)



    Imgur.com is a revelation, thanks.

    Mike
    Last edited by MickyLuv; 02-28-2012 at 09:43 AM.

  9. #9

    Default Re: New Cree headlight. Li-ion batteries problem.

    But on reflection I might be more successful following the Google Picasa tutorial. :-)

    Mike

  10. #10
    Flashaholic* AnAppleSnail's Avatar
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    Default Re: New Cree headlight. Li-ion batteries problem.

    Code:
    Open Bracket IMG Close Bracket http://i.imgur.com/KwWdX.jpg Open Bracket Forward Slash IMG Close Bracket
    Makes
    My biggest light-hog is my camera.

  11. #11

    Default Re: New Cree headlight. Li-ion batteries problem.

    Quote Originally Posted by AnAppleSnail View Post
    Code:
    Open Bracket IMG Close Bracket http://i.imgur.com/KwWdX.jpg Open Bracket Forward Slash IMG Close Bracket
    Makes
    Thanks, that does the trick!

    Mike

  12. #12

    Default Re: New Cree headlight. Li-ion batteries problem.

    Congratulations! You have a MagicShine-like light. The heads are a fantastic value, the batteries.... not so much. They were the subject of a recall by several North American distributors a year or two ago, including Geomangear and Action LED. These distributors were quick to distance themselves from the defective batteries, with Geomangear producing their own using Panasonic cells, now considered an excellent pack even compared to established manufacturers.
    The Magicshine and its clones are frequent topics of discussion on MTBR, and there are several threads discussing the (low) quality of the battery packs, which suffer from pretty much every problem possible in a Li-Ion pack. Here are two threads comparing different versions of the packs:
    http://forums.mtbr.com/lights-night-riding/review-dissection-magicshine-battery-mj-828-a-713595.html
    http://forums.mtbr.com/lights-night-riding/magicshine-battery-dissection-testing-667581.html
    O
    ne of the main problems, besides the poor quality cells, is that the pack isn't balance charged; normally, larger battery packs have individual leads to each battery for charging.

  13. #13

    Default Re: New Cree headlight. Li-ion batteries problem.

    It is not the first time I see this light. It seems to be an exact copy of MagicShine (808 or similar). (I wonder if it is the same OEM light before being branded as MagicShine, or a knockoff?) If this battery proves to be faulty, one can always get a normal MagicShine battery.

  14. #14

    Default Re: New Cree headlight. Li-ion batteries problem.

    Thanks a lot for the spot-on information A1OK and AndreyT. I see I have a little way to go in solving this but thanks to your input I'm no longer in the dark.

    Mike

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