2 Replies Latest reply: Jul 16, 2008 12:26 PM by Thomas Mastin
Bryan Ho Level 1 Level 1 (5 points)
I know that some batteries need to be totally discharged before recharging in order to increase battery life. Do I need to do this with the Iphone battery?

imac 2.8 gHz, Mac OS X (10.5.2)
  • iphoned Level 1 Level 1 (20 points)
    You can 'google' for this information or do a search in the 'search box' of this forum (upper right) using key words. I believe I read somewhere that totally draining a Lithium ion battery (which is in the iPhone) when possible will extend the overall lifetime of the battery. I always do this. When I want to drain the battery when it is near the minimum charge left I watch a Youtube video which seems to drain the battery very fast.
  • Thomas Mastin Level 2 Level 2 (275 points)
    Most people will tell you NOT to drain the battery before re-charging. I would say they are correct, partially.

    Lithium-Ion batteries do not build up a "memory" the same as Nickel Metal Hydride batteries do. Those old NiMH batteries had to be completely drained and recharged almost every time.

    I will say, however, that it is a good idea to "cycle" the iPhone's battery ONCE when you first purchase the device. This "cycling" has the effect of setting the resistence level of the battery. It will make your phone get a more accurate reading of the battery's charge level, and I think it actually gives you a little more charge per cycle.

    What you should do:

    1.) Charge iPhone completely as soon as possible after taking it out of the box.
    2.) Use iPhone until the battery competely discharges, and the phone automatically shuts off (this is a safety feature that prevents you from draining the battery beyond the "point of no return").
    3.) Completely charge iPhone (at least 4 hours on the charger).
    4.) Use iPhone until battery completely discharges a SECOND time.
    5.) Completely charge iPhone a SECOND time.
    6.) You're done.

    You should NEVER have to set the resistence level of your battery again. Some people claim that it is a good idea to cycle the battery once a month. I don't think you should ever have to do it again, or perhaps only once every 3-6 months at the most.

    Keep in mind that a Lithium-Ion battery only has a certain number of charge cycles during its lifetime. Once you use all those charge cycles, your battery will begin to deteriorate to the point it will no longer hold a charge.

    The best way to prolong your battery life and to postpone this "deterioration" is to use the battery as little as possible. Use all of the iPhone power saving features as much as possible.

    So while some people would advise to cycle the battery often, I would advise against it, mainly because while you are playing movies and music and surfing the web in a deliberate attempt to run down your battery, you are actually SHORTENING the life of your battery by using it unnecessarily.

    It's kinda like using a screen saver on an LCD monitor - BAD IDEA. You are just unnecessarily using the device which has a very limited life span to begin with!