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D cell battery gets hot

  1. Jun 22, 2011 #1
    "D" cell battery gets hot

    As a hobbyist, I was playing around with an MP3 player that uses a single alkaline AAA battery. I wanted to see if the player would still work if I attached a "D" cell battery to the device. I went to Radio Shack and puchased a "D" cell battery holder which has two leads.
    I added connectors on the end of each lead and plugged them into the player. The player worked properly.

    I then disconnected the leads from the player and left the "D" cell battery in the holder sitting on the table. It sat for about an hour and when I went to remove the battery, it was HOT to the touch. The two leads were not connected to anything or laying against anything.

    I am truly puzzled as to why the battery got hot. I thought if nothing was attached to the
    leads, it was not completing a circuit. So why did the battery get hot?

    I figured this is a great site to pose this question.
    Thanks in Advance
  2. jcsd
  3. Jun 22, 2011 #2


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    Staff: Mentor

    Re: "D" cell battery gets hot

    Welcome to the PF.

    There is no reason for the battery to get hot unless there was some fault current flowing, or if it was sitting in the direct sunlight or something. You are right to be concerned. Could there have been some other circumstance that caused the battery to feel warm/hot?
  4. Jun 23, 2011 #3
    Re: "D" cell battery gets hot

    berkeman, thanks for the quick response. I had the unit sitting on my kitchen table so it was not in direct sunlight. Retracing my steps, I did play the mp3 player with the D Cell battery for 30-45 minutes, I unplugged battery from the MP3 player but did not notice it being hot at that time. I left the "D" cell (still in the holder) sit for about an hour. When I went to move it that's when I noticed it was hot. The leads were not connected.
    I think I have a defective battery. I will run through this test scenario again. I will reuse the same battery and see if I get the same results. Then I will retest it with a different "D" cell and see what results I get.

    I will post the results of my test.
    Thanks Again
  5. Jun 23, 2011 #4


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    Science Advisor

    Re: "D" cell battery gets hot

    What type of "D" cell was it? Was it Zinc Carbon, Alkaline or a rechargeable?

    Did you test the voltage of the battery afterwards. Was it "flat"?

    The most common reason why that would happen is that the battery got short circuited. The two wires don't need to touch each other, they just need to contact some common conducting object, eg piece of metal cutlery for example.

    Yes it could be just a random failed battery but the chances against it are about a billion to one. I'm guessing that the chance that you inadvertently shorted it are considerably higher than that.
  6. Jun 23, 2011 #5
    Re: "D" cell battery gets hot

    berkeman/uart thanks for your responses

    I ran through the scenario as described in my previous posts twice, once with the original D cell battery (that got hot)
    and also with a brand new "D"cell. Both are alkaline batteries, the one that got hot measured 1.4 volts and the brand
    new one measured 1.5 volts.

    This time when I disconnected the leads from the MP3 player, I taped up the postive lead to be sure there was no
    chance of a short circuit.

    In either case, I could not reproduce the result of the battery getting hot. I have to surmise that the leads must have
    been touching and this is what originally caused the battery to heat up. I have noticed the leads from the battery holder
    do curl toward each other.

    Based on my IT background, you can chalk this up to a user error.

    Thanks so much for your input.
  7. Aug 1, 2013 #6
    Its the battery sometimes

    I had it happen last week (24 July 2013) to a Duracell D cell in a flashlight. One battery dated 2005 that was still good had gotten hot inside the flashlight. I had trouble with the switch and left it on the kitchen table. An hour later I touched it and wow. Took it apart to find one battery (D size) hotter than can be touched. I threw it out the window on the grass. The other battery was cold. The plastic flashlight was very hot. An hour later I measured the volts on the now cold battery and it was down to 1.0 volts....dead. The other battery was still 1.4 volts and dated 2012. So it can happen. Its an internal short inside the cell. Dont have any idea why it started doing this. I did not bang the battery or high quality flashlight. I thought I would post this because I had it happen 5 or 8 years ago and I thought I was loosing my mind. It really did happen last week the way it happened before.

    Steve Stillman
    Shrewsbury, MA
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