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Thread: Aging battery question

  1. #1
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    Aging battery question

    I have some older batteries, and their ability to hold a charge is diminishing as is to be expected. The question that arose as I just charged more often, is, does max drain capacity diminish over time as well. Should I be increasing resistance to reduce the demand on the battery as it ages?
    The obvious answer is to buy new batteries, and I will, but knowing whether age of any battery should be taken into account when doing my Ohms law calculations would be reassuring.
    Any ideas?

  2. #2
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    This is not an answer as such because I actually don't know.

    But I wouldn't exceed the C rate of the battery. For example, say you have a battery capable of 20A and it's a 2000mAh (or 2Ah) battery. The C rate is 10 (20/2). If the capacity through aging has dropped to 1000mAh (or 1Ah), then I would still ensure I didn't exceed the C rate so restrict the current draw to 10A.
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  3. #3
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    So, not the answer is yes. Thanks gt. C rate is new to me, and not sure I quite understand it. Can I measure mAh, can't seem to find it on my multimeter. I think my new rule of thumb will be, "When battery capacity reduction is noticeable, double minimum coil resistance" I actually did that already, but only through the cowardice born of ignorance.
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  4. #4
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    Cowardice born of ignorance, how very liberal of you.
    Have a squizz at this link, the battery University has lots of good reading.


  5. #5
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    My Sony 18650's are getting tired. I'd say they're charging at about 80% compared to when they were new. Not bad considering I bought them back in March 2014.
    I use a kick with them and they still seem to work fine for now but it's really only a matter of time. The plan is to retire them soon but I'm not sure when.

    Thanks for the C rating info.
    Peter

    My last cigarette... 3rd April 2014

  6. #6
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    It also depends on your device A low power regulated device will be okay without increasing the resistance. I would err on the side of caution with a mech device though.

    Information on batteries Lithium-based Batteries Information If you have a look around that site, I'm sure they will explain C rates better than I could
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  7. #7
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    Snap MrGruff
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  8. #8
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    Quote Originally Posted by Coxy View Post
    So, not the answer is yes. Thanks gt. C rate is new to me, and not sure I quite understand it. Can I measure mAh, can't seem to find it on my multimeter. I think my new rule of thumb will be, "When battery capacity reduction is noticeable, double minimum coil resistance" I actually did that already, but only through the cowardice born of ignorance.
    mAh is the capacity rating of the battery. For instance, AW IMR18350 are 700mAh. Some battery chargers will display the amount of energy (in mAh) put back into the battery while charging.
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  9. #9
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    Thanks all, battery university, wow!

  10. #10
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    Quote Originally Posted by MrGruffy View Post
    Cowardice born of ignorance, how very liberal of you.
    Have a squizz at this link, the battery University has lots of good reading.
    Yep
    And a well timed reminder to either do the checks, or do a replacement rotation
    Thanks gruff!

 

 

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