Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Battery Programming Question

  1. Jan 17, 2016 #1
    Hi guys I'm not sure if this is the best place to post this but I couldn't find anywhere else.

    Would it be possible to program a cell phone charger to detect when a phone is at 20% and then it will start charging? But it won't start charging before 20%. Then it will charge it up to 99% and then stop charging until the phone reaches 20% again.

    Let me know if you have an idea how to go about this. Specifically for iPhones and Galaxies, etc. The most popular phones.
    Even if you can't give me specifics maybe just give me an idea of how to do it? I am not a programmer so maybe try to keep the lingo somewhat easy for me to understand, Thanks!

  2. jcsd
  3. Jan 18, 2016 #2


    User Avatar
    Science Advisor

    In the bad old days with NiCd and NiMH batteries that was the hallmark of an advanced charger. Now, with Li-Ion batteries, such a charger would most likely shorten the lifetime of the batteries.
  4. Jan 18, 2016 #3


    User Avatar
    Gold Member

    Can you share the reason you want to do that?

    I've read that LI-Ion batteries have the longest life at 70%. Discharging them deeper does decrease their life, but I don't know how much.
    Li-ion lifetime is related to the total charge amout. If you run off the charger whenever it is connected you maximize Li life.

    I know no way to get at the charger code short of rooting your device.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook