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  1. #1
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    Quick tips: Improving your cheap 18650 cell charger

    The other day I bent the contacts outward on my cheap D/X DSD charger in hopes of improving it's ability to charge the battery cells. I tried this because sometimes when I charge my cells, instead of getting the green ( charged ) light I was getting the alternating green/red flashing light. Since bending out the contacts I now get the green charge light on all my chargers. Wish I did this a year ago. Since this works so good on the chargers It would probably be a good idea to do the same on your cell holders every once in a while as well.

    Another quick tip for improving electrical contact. When I was a kid I used to play with the electrical H.O. slot cars. I discovered that if I cleaned the electrical contacts of the tracks and the cars with a pencil eraser, the cars would go faster. It made a humongous difference.

    Having poor electrical contacts is the same as adding a resistor in series with the circuit. It will add a small voltage drop which also affects current flow. Tight pressure on electrical contact points is a must ( unless they are soldered of course ). I should also note that poor soldered joints can cause the same problems. Because torches have lots of electrical ( pressure )contacts ( metal against metal, no solder ) it is a real good idea to service those contacts on a regular basis. You will be surprised at how much a difference it makes, especially with the cheaper torches.

    If you have a tip for increasing electrical contact on pressure points please be sure to comment. This old Cat loves to learn new tricks.

  2. #2
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    They're several contact enhancers on the market. My fav is Deoxit. I have found the result of using it simply amazing! http://www.amazon.com/Booster-Electr.../dp/B0002BBVN2 I have been using this stuff for years. I worked on telemetry on Air Force jets. Bad connections were always a headache; jets are a terrible environment for electronics gear. I used Deoxit on all contacts to enhance conductivity. I use it on the contacts on my bicycle computer. That way sweat and such doesn't corrode the contacts. Cat, you are correct in saying "Having poor electrical contacts is the same as adding a resistor in series with the circuit. It will add a small voltage drop which also affects current flow." The poor contact also adds heat, IR losses.

  3. #3
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    Just give all of the contacts including battery ends a clean with surgical spirit (rubbing alcohol).

    If you are in the UK then this stuff from Maplins is great http://www.maplin.co.uk/Search.aspx?...aner&source=15

  4. #4
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    Been using Servisol contact cleaner that's on the same Maplin page YB pointed to, for 30 odd years. It's the best!

  5. #5
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    I only get the worrying, red / green flash when I put 2 fully charged batterys in there, never quite worked out why they don't just go red.

    I guess the charger is seeing a voltage it can charge, then the batterys protection sees over charge and cuts it, so the charger cuts then the protection cuts so back to green, the repeat.

    It is odd though.

  6. #6
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    Great tips indeed! I've been considering using rubbing alcohol but knew there must be something better. Looks like it's Servisol for you blokes in the U.K. and Deoxit for us dudes in N.America. I guess if it's good enough for the U.S. Air Force it's good enough for me. I like the idea of the bottle with small brush. Great for tight spaces without too much mess, especially on threads.

  7. #7
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    Quote Originally Posted by Turveyd
    I only get the worrying, red / green flash when I put 2 fully charged batterys in there, never quite worked out why they don't just go red.

    I guess the charger is seeing a voltage it can charge, then the batterys protection sees over charge and cuts it, so the charger cuts then the protection cuts so back to green, the repeat.

    It is odd though.
    Looks like the contacts on mine are pretty worn. I might have to put some sponge-like foam behind them to increase the pressure. When I bend mine out they just go back to former after the first charge. Humm....I just realized that the alternating G/R light might be coming on because the batteries I'm charging might have lost enough capacity to not trigger the voltage level for the green led. Don't know why I never thought of that before. Unfortunately I don't have a multi-meter sensitive enough to detect the smaller ( tenths of a volt ) voltages.

    Turveyd, on mine the R/G flash indicates standby mode. Red indicates the cell is charging. Green , the cell is fully charged.

  8. #8
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    Just got me a new charger this week for my 18650 cells. The Ultrafire WF-139 two bay charger. Unlike my DSD chargers this one has a separate circuit for each bay. I threw two ( nearly fully charged ) cells in to see what would happen. Damn, those cells charged for almost two hours! When they were done I popped them back in the torches and ...WOW!...what a difference! I guess that means my DSD chargers weren't working as good as I thought they were. Wish I had a good digital mult-meter to test the charge. If I did I would of known about this sooner.

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