Previous 1 2 3 Next 37 Replies Latest reply: Feb 27, 2013 7:58 PM by Bandit7 Go to original post Branched to a new discussion.
  • Bandit7 Level 1 Level 1 (60 points)

    Here is the spec sheet from Apple on the 4s.

     

    http://www.apple.com/iphone/iphone-4s/specs.html

     

    What is missing are any battery specific specs on any of the IPhones. But they provide battery specs in watt-hours for all of the IPads..

  • Bandit7 Level 1 Level 1 (60 points)

    You mentioned that if the iPhone 4s is getting hot it may be overcharging not due to any mistakes with the Theory! :-)

    I now can totally agree and I understand that. Thanks by the way!

     

    But some possible malfunction  with the iPhone regulation system is possible. So while charging it I forgot to mention or actually I left it out completely because it is a guess, not a measured result, but both the iPhone and the apple 5 watt source were what I consider to be excessively hot.

     

    I dumped all power from the Iphone 4s and then recharged it on one of the apple 5 watt cubes where it is registering 6.5 watts draw. I calculated the 80% capacity level since I noticed by measurement that Apple IOS charge regulaters built into the device INTERNALLY, act very similar to my higher end solar controllers. From 0% to 80% there is the bulk charge level, maximum charging level, then at 80% the apple IPhone starts asking for less voltage. It is the same transition level as the solar controller has and they both went into the "Absorption" Phase where lower charge levels are applied to be able to fill the battery to 100%. After 80% of capacity was reached voltage on my meter started dropping down from 6.5 watts to 5.9 watts, then to 5 watts, this was at about 87% capacity, then down to 4.5 watts, then to 4 watts at 90% capacity and then to 3.7 watts, to 3 watts, and finally to 1.1 watts at 100% capacity where it stayed... Just like the "float" charge of a solar controller only with a higher percent level of float charge. But then one of the links you sent mentioned that apple IOS devices will still pulse charge for an hour after 100% is supposedly achieved, but that they deliberately kept the variations off the readable capacity so consumers would not get confused.

     

    So yes they have an internal very smart charging and regulation system! But it isn't calibrating with what the specs should be! Charging time at bulk rate to 80% of capacity (1136 Mah as I calculated based on 1420 Mah full capacity at 3.7 volts ) was reached in 76.5 minutes. But that includes time spent restarting up the phone as I let it totally uncharge and shut down. On 3% it rebooted. At 5% charge I went into,settings and shut off data function, I shut off Wi Fi and engaged "airplane" mode. I also made all of those bottom icons get all wiggly, and shut them down too. :-)

     

    So just by calculating approximate full charge period at bulk charge to 80% along with the time it took tells me nothing precisely. It does put charge rate at a bit less then 1C. However I am very aware that any number of voltage and wattage combinations could produce the same results. As you pointed out:

     

    Scientific method must set up a defined set of parameters for a test, that when repeated by others with the same parameters produces the same results. I learned that through school (psych major) and my own readings of many books. ( not enough obviously )

     

    I hope I made some sense in this post. Which I doubt. I also think I can narrow down the % of C that could produce a better "guess"

    But I can't measure the power between the apple 5 watt source working at 6.5 watts between the phone and the power source! Very frustrating.

  • crh24 Level 3 Level 3 (920 points)

    Bandit7 wrote:

     

    Here is the spec sheet from Apple on the 4s.

     

    http://www.apple.com/iphone/iphone-4s/specs.html

     

    What is missing are any battery specific specs on any of the IPhones. But they provide battery specs in watt-hours for all of the IPads..

    They don't release the data important here, i.e. what is the charge current the phone/pad is expected to draw.  What is the maximum it should ever draw when charging?

     

    Without that information you can't really say that at 6.5W your phone is defective even if it appears to be very hot to the touch.

  • crh24 Level 3 Level 3 (920 points)

    Bandit7 wrote:

     

    <...>

    So how can a 5 watt rated power source put out 6.5 watts??? I got the same readings from two apple 5 WATT cubes, and when I tried a generic 5 watt power source the same iPhone 4S was drawing 6.2 Watts! I believe that it would have pulled the 6.5 watts with the generic 5 watt 5 volt cube but that the generic cube was unable to deliver more then the 6.2 power draw from the Iphone 4s. As for specs on the iPhone 4S it has a 3.7 volt, 1420Mah capacity, or 25 watt hours is what I believe is on the apple spec sheet on their site. But the 1420 Mah is cited in every website I researched.

     

    <...>

    The battery capacity doesn't really say anything about the maximum charge current the phone will pull from a 5 Volt source.

     

     

    Bandit7 wrote:

     

    <..>

     

    As for how it is possible for the IOS device to pull 6.5 Watts on several different 5 watt power sources I am at a loss to figure out and am hoping that perhaps you can understand this "phenomena" much better then I can.

     

    <...>

    Probably just a bit of room the designers put into the brick.  If they set it at exactly 5W then it could be damaged when connected to a phone that is out of spec possibly resulting in a dead phone and a dead supply.

     

     

    Bandit7 wrote:

     

    <...>

     

    I always assumed that a rating on a reliable power source device could not be exceeded. But that is the case here. If it was only exceeded by 10% I wouldn't think much about that. But it is exceeded by 30% of its ratings. 5 Watts x 1.5 Watts

    It does seem to me to be a bit excessive, but again without knowing the specifications for the phone and supply one can't say for sure.  I can give a bit of anecdotal evidence--I, or my wife, have owned 9 iPhones.  None of them ever gotten more than a 'little' warm when charging. That leads me to believe that your phone might be out of spec, but it's just a belief not a certainty.

  • Bandit7 Level 1 Level 1 (60 points)

    I know. It kinda seems very one sided. But indeed without that data, "hot" is meaningless. And with the data, the phone could be working well within normal specs regardless of heat, a subjective term at best.

  • Bandit7 Level 1 Level 1 (60 points)

    My two other IPhones which are 4's are also charging above 5 watts. At about 6.0 watts. I am aware that this could be within parameters. And the Kill a watt meter may not be accurate at that level. But I only got the idea of using mine from watching the you tube video that was in that thread you mentioned. And he used the very same model that I have in that video. Which reads a perfect 5 watt draw on the AC SIDE.

  • Bandit7 Level 1 Level 1 (60 points)

    So what do I do from here? I have the Apple extended 2 year thing. But all of this "evidence" is not evidence it is anecdotal at best. I think that even if they were to replace this phone, would you know if the one they might give me would be new, or possibly rebuilt, what's it called, factory conditioned or something like that?

     

    I probably should just leave this be. It was a by product of learning about the internalized charging systems. What are your thoughts on this?

     

    It's kinda amusing in one way, and kind've not funny in another way. It is a technical labyrinth!

  • Bandit7 Level 1 Level 1 (60 points)

    My other IPhones don't get "hot" they get a bit warm as you describe. Oh yes, the joys of high tech land...

    And to think, half of the worlds population have never even seen a rotary telephone. Lucky guys...

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