where Does Current Go

Discussion in 'General Electronics Chat' started by loosewire, Sep 7, 2010.

  1. loosewire

    Thread Starter AAC Fanatic!

    Apr 25, 2008
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    My mouse died ,the indicator lite was out,
    I switched the old batteries around.The
    indicator lite came on the mouse Is working.
    time quit 5:18. How long will It takes for
    current to equalize. My low battery pop -up
    has came up once.Any educated guess on how
    long the old batteries will last now and why.
    What powers the pop-up signal,the mouse
    or computer.2-double A"s
     
    Last edited: Sep 7, 2010
  2. Audioguru

    New Member

    Dec 20, 2007
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    The low battery voltage triggers the "low battery warning".
    WHY DON'T YOU REPLACE THE WORN OUT BATTERIES WITH NEW ONES??
     
  3. tom66

    Senior Member

    May 9, 2009
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    Swapping batteries around is only going to delay the inevitable.

    It's just like this 'trick' my dad taught me: take the battery out, and rub it on the carpet. Apparently, the rubbing on the carpet causes it to build up a static charge. But this is a psuedoscientific myth; what is actually happening is the voltage across the battery temporarily recovers, allowing the remote/mouse/whatever to work for a few more minutes, but not long. There is certainly no static build up.

    I highly suggest you get some rechargeables, I use them in almost all my wireless mice, I have a little USB charger plugged into one of my computers. The Ni-MH batteries cost a lot more (2x-3x more) than ordinary alkalines, but last 1,000 cycles or so and cost virtually nothing to recharge.
     
  4. marshallf3

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    Jul 26, 2010
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    What it does is clean some of the oxide off the battery contacts.
     
  5. tom66

    Senior Member

    May 9, 2009
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    Good point - I never thought of that. But I think the added resistance from the oxide would only increase the resistance of the battery slightly so for low drain applications like mice and remote controls it doesn't make much difference. But I wouldn't know - I wonder how much oxide does affect resistance?
     
  6. Wendy

    Moderator

    Mar 24, 2008
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    With someone using McScrooge as an avitar this should be obvious. :D
     
  7. retched

    AAC Fanatic!

    Dec 5, 2009
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    Actually its Scrooge McDuck..I believe. ;)
     
  8. loosewire

    Thread Starter AAC Fanatic!

    Apr 25, 2008
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    I just remembered someone asking the question,
    so since we had the real thing ,I asked the
    question.I did change the batteries,I just wanted
    to prove a point.Its like when you get a weak car
    battery,let It set,the juice go back into the battery
    from the cables,you get one more start sometimes.
     
  9. Wendy

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    Mar 24, 2008
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    Batteries wear out. Some batteries are better than others, such as lithium. There are usually tricks to squeeze out more life, but it is only stopgap, once they start showing signs of being discharged it is time.

    Most rechargeables only go to 1.20 volts instead of 1.25, which may not sound like much but doesn't help their case. NMIH or NMH (nickle metal hydride) are better than most, they carry a deeper charge and can provide more current.

    Over time I expect there will be better. This technology has a lot of active R&D behind it.
     
  10. retched

    AAC Fanatic!

    Dec 5, 2009
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    Its not letting the juice back from the cables.

    You give the battery acid more time to eat more lead and 'generate' more power.

    Then you may get a little boost.

    Same with taking out the batteries and putting them back in. It gives the batterys some time to self-charge.

    It has nothing to do with current being caught in the cables.
     
  11. marshallf3

    Well-Known Member

    Jul 26, 2010
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    Once again it's just removing some oxide. First thing I do when at a friend's house and he's cursing his remote control. I ask for a pencil eraser and wipe the battery ends as well as the contacts in the remote. A pocket or kitchen paring knife works especially well for this.

    Results are of course mixed. Often the batteries are still good and keep working for another year if it was just oxide related but if they're pretty well dead you're buying little if anything.
     
  12. tom66

    Senior Member

    May 9, 2009
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    A Ni-MH cell usually works around 1.2 volts nominal, but this is usually okay, because most devices are designed to work with alkalines near their end of life (about 1 volt.) I've found most devices work adequately with Ni-MH cells, but typically they will show a low battery icon, such as 2/3rds battery full on my camera and fairly quickly it will drop to one thirds and then empty (within about 5 minutes.)
     
  13. retched

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    I will agree that removing some oxide does play a role.

    However, rubbing the sides of the batteries (not the terminals) on the rug does not remove oxides.

    It does "heat" the battery. This small heating allows the chemical reaction that is taking place inside the battery to produce a little more power, while the time out of the device allows a little 'self-charging'.
     
  14. marshallf3

    Well-Known Member

    Jul 26, 2010
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    Yea, if he's rubbing it on the side that's the cause. You might surprise him with how you can recharge a battery by simple solar power - set it in the hot sun for an hour. :)
     
  15. retched

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    That will work.

    It seems people have been storing batteries in the refrigerator for years to prolong shelf life, but still fail to understand how temperature plays a role in a batteries operation.

    Even just handling the batteries are going to make them warmer than leaving them alone.

    The act of removing the batteries and putting them back into the device will warm them with body heat.

    By the way, don't put 9v batteries in your pocket unless you want to burn an image of a coin into your thigh. ;)
     
  16. t06afre

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    May 11, 2009
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    Lol having a imprint of say George Washington or John F. Kennedy. On your "John Tomas" will in most circles, be considered quite kinky. By the way is George W. Bush is engraved on any coin yet.
     
    Last edited: Sep 9, 2010
  17. Wendy

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    He's got to die first, I think.
     
  18. retched

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    Agreed.

    Wait! what? ;)
     
  19. marshallf3

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    Jul 26, 2010
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    Same goes for about any battery if you've got a lot of charge &/or keys in there with it.

    A bit of tape works wonders here.
     
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