iPhone Battery Guide and Charging Tips (3Gs / 3G / Original)

Discussion in 'iPhone Tips, Help and Troubleshooting' started by _Refurbished_, Jul 18, 2008.

  1. _Refurbished_ macrumors 68000


    Mar 23, 2007
    This thread was created to help maximize the potential of your iPhone's battery. If you read something you disagree with, disagree. If you wish to have something added to this original post, please comment and state what information should be added. I take no responsibility if you damage your iPhone by doing something mentioned in this thread.

    Please don't flame.

    Rated Battery Life

    3Gs vs. 3G Battery Test: http://crave.cnet.co.uk/mobiles/0,39029453,49302814-4,00.htm
    (3GS up to 45% better than 3G, despite Apple's claims)

    iPhone 4
    Talk Time - 3G 7 hours / EDGE 14 hours
    Web Browsing - 3G 6 hours / WiFi 10 hours
    Video Playback - 10 hours
    Audio Playback - 40 hours
    Standby Time - 300 hours

    iPhone 3Gs
    Talk Time - 3G 5 hours / EDGE 12 hours
    Web Browsing - 3G 5 hours / WiFi 9 hours
    Video Playback - 10 hours
    Audio Playback - 30 hours
    Standby Time - 300 hours

    iPhone 3G
    Talk Time - 3G 5 hours / EDGE 10 hours
    Web Browsing - 3G 5 hours / WiFi 6 hours
    Video Playback - 7 hours
    Audio Playback - 24 hours
    Standby Time - 300 hours

    Talk Time - EDGE 8 hours
    Web Browsing - WiFi 6 hours
    Video Playback - 7 hours
    Audio Playback - 24 hours
    Standby Time - 250 hours

    Power Saving Tips

    #1 - Always go to the home screen before putting your iPhone in standby mode. If you are running an App and hit the Sleep/Wake button to turn the screen off, the application will still be running in the background and can severely drain your battery.
    #2 - Disable 3G on long calls (Ex: business calls, calling your cable company, or calling ATT Customer Service :p). Call quality on EDGE is quite good compared to 3G.
    #3 - If your apartment / house has a weak 3G signal, definitely turn off 3G until you leave your home. My apartment has a very weak 3G signal. The phone switches networks constantly if I have 3G enabled, which murders my battery. I use EDGE while I'm at home w/ WiFi for data. When I leave my home, I turn on 3G.
    #4 - Enable WiFi in your apartment / house when WiFi is available. Use WiFi instead of 3G or EDGE for web browsing. WiFi is (with a strong signal) faster than 3G or EDGE. WiFi also uses significantly less battery power than any cellular network.
    #5 - If you only use WiFi hotspots, keep WiFi disabled. Enable WiFi when you enter a hotspot.
    #6 - If you don't need GPS, disable Location Services. When Location Services is enabled, your GPS antenna is activated. The GPS antenna will continue to drain battery life, even if you aren't using an application that needs Location Services.
    #7 - Disable Push notifications, unless needed. It is estimated that your battery life will decrease by 20% (about an hour) with Push enabled. Increasing your fetch interval to an hour or above will also increase battery life.
    #8 - Disable Bluetooth if you have no Bluetooth devices (duh). If you're like me and use Bluetooth in your car, I would just leave Bluetooth ON for convenience so you don't have to enable Bluetooth every time you go for a drive. More trouble than it's worth.
    #9 - Using App Store programs may HEAVILY decrease battery life. Games (especially 3D) are notorious for killing your battery. Don't be surprised to get 2 - 3 hour usage statistics while gaming.
    #10 - Enable Auto Brightness
    #11 - If you have no service at all, use Airplane mode. With no service, your phone will constantly look for a signal, which kills your battery very quickly. Airplane Mode will let you use your phone, but you won't be able to dial or receive calls.
    #12 - Make sure Auto-Lock is set @ 1 minute.
    #13 - If you mainly use your phone for talking / texting / email / gaming, using EDGE will offer a similar experience, but your battery life will increase significantly.

    Web Browsing: 3G vs. EDGE vs. WiFi

    This graph demonstrates why it doesn't make sense to use EDGE for web browsing vs. 3G or WiFi. Realize that 3G is usually at least 2X as fast as EDGE, but you don't get 2X the battery life by switching to EDGE. You get more production done with 3G enabled, in less time, therefore saving battery life compared to browsing with EDGE .

    Graph shows usage statistics (100% Battery Life > 0% Battery Life)

    3G vs. EDGE Browsing Explained (using the iPhone 3G)
    (Web Pages Accessed Are Theoretical)
    3G Enabled Web Browsing = 197 Minutes (Before battery is depleted) | 394 Web Pages Accessed
    3G Disabled (EDGE) Web Browsing = 243 Minutes (Before battery is depleted) | 243 Web Pages Accessed

    The numbers above are based on the assumption that it takes 1 minute to fully load a web page using EDGE and 30 seconds to fully load a web page using 3G. (Based off of Apple's claim that 3G is 2x as fast as EDGE, which seems to hold up in real world tests)

    As you can see, enabling 3G will allow you to load about 60% more web pages per charge cycle than with EDGE enabled, even though using EDGE conserves battery life.

    iPhone Charging

    Initial Charge (a few theories out there, I felt this is the safest route to go)
    #1 - Buy the iPhone. Do not use the iPhone.
    #2 - Initially charge your iPhone with the wall charger for 3 hours. (Do not use your phone)
    #3 - Once fully charged, let the iPhone's battery fully drain. (You can use your phone)
    #4 - Keep the iPhone off for 2 hours.
    #5 - Fully charge your iPhone and allow the battery to rest in the fully charged state for two hours. (You may use your iPhone during this time as long as the iPhone is plugged in)
    #6 - Repeat step's #3/#4 a maximum of three times if you feel your battery indicator is inaccurate.

    Everyday Charging
    #1 - Charge your iPhone throughout the day when available. Charge EVERY night, regardless of charge level. This will keep your battery active, which is healthy for the iPhone's battery.
    #2 - Use a wall charger or car charger w/ rated output 5V 1A. Computer chargers might not charge when the computer is in standby mode.
    #3 - You cannot overcharge your iPhone. You don't need to disconnect the iPhone from the charger after it's done charging. Once fully charged, the iPhone will run strictly off of AC power and will not damage the battery.
    #4 - Every two months, make sure you fully charge and fully drain the battery, in one cycle. This calibrates your battery indicator. If you fail to do this, your indicator will become inaccurate. Calibrating your battery does not improve battery life.
    #5 - If you ever need to store your iPhone for any reason, make sure your battery is stored @ roughly 50% and in a cool environment.
    #6 - Always charge your iPhone out of its case (assuming you can easily remove the case). Charging your iPhone inside your case will make the iPhone hotter, which is bad for the battery.
    #7 - Charge your iPhone in a cool location. Charging your iPhone in a cool environment has a tremendous impact on your battery's lifespan. The colder the location you use to charge, the more charging cycles you can complete without your battery deteriorating. Avoid charging in direct sunlight. DO NOT PUT PUT YOUR IPHONE IN THE FREEZER! :)
    #8 - Use properly rated chargers. Using chargers that are not properly rated will have a huge impact on your battery's lifespan. Make sure your car charger has the same rating as the official Apple charger. The official Apple wall charger is rated as follows:

    Input: 100 240V ~ 50/60 Hz 1.0A
    Output: 5V 1A

    Heat vs. State of Charge vs. iPhone Battery
    "The speed by which lithium-ion ages is governed by temperature and state-of-charge. Figure 1 illustrates the capacity loss as a function of these two parameters." - Battery University

    This graph shows long-term storage. (Ex: You buy a new iPhone and need to store your old one as a backup)


    Your iPhone's battery doesn't like to be stored @ 100% charge. Storing your iPhone @ 40% charge is recommended. Storing your phone when it's fully charged, in a hot environment, will SEVERELY shorten the battery's lifespan. Keep this in mind when storing your laptop battery, as well.

    More information can be found here:

    iPhone 3G Battery Tests:



    Articles Testing The iPhone 3G's Battery Life

    Setting Your iPhone As New (Without erasing App Store data or game saves)

    There have been reports that resetting specific settings on your iPhone will help restore battery life. Worth a shot if you have seen a decline in usage per charge cycle.

    As Posted by ThaSpaz here: http://forums.macrumors.com/showthread.php?t=761046
    *** Warning: Do not hit Erase all Content and Settings *** Guess what that does

    Go to Settings>General>Reset>Reset all Settings
    I have selected "Reset all Settings" and Here are my findings. Enjoy!

    #1 - It reset my home screen icon positions
    #2 - It reset my network settings
    #3 - Did not remove my Safari bookmarks
    #4 - Mail settings stayed
    #5 - iPod settings are back to default
    #6 - Store sign-in settings reset. I am signed out.
    #7 - Backlight is back to 50%
    #8 - All General settings are back to default
    #9 - Wallpaper is still intact
    #10 - Sounds have been set to default.
    #11 - Notes are still intact
    #12 - Photos are still intact
    #13 - SMS message conversations unchanged
    #14 - Phone favorites unchanged
    #15 - Third party app settings remain untouched (I'm still logged into Twitterrific and all my settings are the same)

    Testing For Defective Batteries

    As for defective batteries. First and foremost, charge from the wall. I tried charging my iPhone from my iMac and had a 20% charge the next morning. I'm not saying you can't successfully charge from your computer, but to diagnose a problem, I would give the wall charger a shot.

    #1 - Reset your iPhone. (To perform a soft reset, press and hold the iPhone’s Sleep/Wake button and the Home button for several seconds, or until you see the Apple logo on the screen)
    #2 - Fully charge your battery.
    #3 - Fully drain the battery.
    #4 - Fully charge, again.
    #5 - At this point, your battery indicator should be more accurate.
    #6 - If your battery is still really weak, head to the Apple Store to potentially exchange your iPhone. (1 year warranty)

    Defective Batteries Past Warranty Coverage

    - Apple isn't required to replace your phone due to battery issues (after 1 year). However, there are occasions where Apple will replace your phone past its warranty. My father was having issues with his battery after his warranty expired. He went to the Genius bar and they replaced his phone without hassle. This was an original iPhone. YMMV.

    Battery Extenders

    Mophie Juice Pack for iPhone 3G & 3GS - https://www.amazon.com/dp/B001E42QB...iveASIN=B001E42QBW&adid=0X0JD5X6AKPKYNMY96MC&

    Tekkeon MP1200 iPhone Battery/iPhone Sleeve - https://www.amazon.com/dp/B001NJ09H...iveASIN=B001NJ09HG&adid=1GE8WEM6R6M2CKZJ06XH&
  2. firewood macrumors 604

    Jul 29, 2003
    Silicon Valley
    The battery guage out of the box isn't calibrated. The remaining life indicator is very likely incorrect until you've done at least 1 (some say 2, some say 3) complete 100% (fully charged plus an hour) to 0% and recharge to 100% again battery cycles.

    If you think the battery life of your brand new iPhone is getting better because you changed something, turned off push or something, it may just be the battery gauge reading more accurately as you use it, and nothing you did. Wait until you've cycled the charge before trusting any battery life methods you think you've found, or you'll just be falling into a trick of your mind.
  3. _Refurbished_ thread starter macrumors 68000


    Mar 23, 2007
    I would agree. However, turning off the features mentioned above does have a serious impact on battery life. But yes, you should cycle the charge at least one time. After a few days, mine was reading accurately and I only did one full charge cycle. I guess YMMV. I updated the information slightly to reflect your information. Do you have a link talking about this? I'm curious to see it.
  4. ThinkingDog macrumors newbie

    Jul 11, 2004
  5. StingerT125 macrumors 6502a


    Jun 3, 2008
    Dutchess County New York
  6. Sphyrna macrumors regular

    Jul 9, 2008
    Very nice having all the information in one post! Thanks!! I vote for a sticky!
  7. Kadman macrumors 65816


    Sep 22, 2007
    Definitely agree. This should be a sticky. So long as others offer input in a positive manner (i.e. no flaming arrows) and the OP updates with this new info when relevant, this should be a great project!

    My input:

    I find it odd that Apple recommends using EDGE vs 3G for calls given that I thought (please correct me if I'm wrong) that one of the touted advantages was the ability to use voice and data at the same time (i.e. be in a call, check for a new email and continue conversation, etc)

    There should be no reason to shy away from the computer as the primary charing device, so long as your computer isn't set to auto sleep. More than likely what happened in your "20%" charge situation is that your Mac went to sleep and the power to the USB ports shut down in the process.

    I also don't agree with part of your red text stating not to let the battery drain down all the way during normal use. It should be fine. If your concern is about battery damage due to "zero" charge levels, the circuitry shuts things down far before you get to that point. The only time you should fear damage is during prolonged storage (i.e. many, many months) without any charge cycles.

    Great job on the thread!
  8. ijohnw macrumors regular

    Jul 3, 2008
    Eastern NC
    Excellent Post!

    I just got off the phone with apple support..i was roughly getting just around 4 hours of use with my phone running on edge all day with all the extra services off - acting like a normal 1st gen iphone. She told me it is about half of what I should be getting...

    They now have an iphone 3g replacement program...i am getting a new iphone 3g sent to me overnighted and should be here Monday morning and I have to send the original one i have back to apple...$29 dollar for shipping...the closest apple store is two hours away so I guess it is worth it...otherwise I would have had to go to apple store where they have no iphones in stock and tried to get it replaced...
  9. acousticbiker macrumors 6502

    Jun 28, 2008
    I've found that turning off Location Services (GPS) makes a significant difference.
  10. _Refurbished_ thread starter macrumors 68000


    Mar 23, 2007
    Thanks for the input. The 40% information has been pretty universal from what I've researched about Lithium Ion. The graph I posted, if correct, means the 40% charge technique does extend the life of your battery. I think I'll stick with that, unless I am proven wrong by multiple sources.

    As for my 20 % charge issue, my computer is set to never go to "sleep", only to turn the monitor off. I'm not sure why I had that issue, but I don't recommend using the USB charger anyway, as it is not as good of an energy source.

    You bring up a very good point with the simultaneous 3G voice / data. I will incorporate that into the tips.
  11. Ferris23 macrumors 68020

    Sep 24, 2007
    This conflicts with another seemingly informed user who said that LiIon batteries don't need and shouldn't be fully drained.

  12. Julien macrumors G4


    Jun 30, 2007
    Where do you see this conflict? The OP clearly (and correctly) states to not run your LiIon batteries completely dead. When LiIon's drain completely they grow a crystal structure that diminishes their recharge ability. However you must re-calibrate the charging meter (LiIon's have a complex recharge control system since the batteries are volatile) from time to time (about once every 30 charge cycles) by completely discharging the battery.
  13. FearlessFreep macrumors 6502a

    Jul 15, 2008
    Northern Virginia, USA
    Great post, I'd clean up the charging section a bit. There's no question the battery needs to be calibrated by the full discharge-charge cycle 2-3x initially. The 40% rule is good and is in line with other recommendations concerning "topping off" of LiIon batteries to maximize battery lifespan.

    And for about the 100th time, letting your battery run down until the device shuts off will do no harm. The battery and iPhone are set to suspend long before it reaches a deep discharge that would do permanent damage.
  14. firewood macrumors 604

    Jul 29, 2003
    Silicon Valley
    LiIon batteries should not be fully drained; but the built-in battery/charge controller logic won't let you - the iPhone will shut down way before the battery is really fully drained to avoid damaging the battery.

    According to the manufacturer's data sheets, LiIon batteries will last a lot longer ("wear out" slower) if not discharged to shut-off and deep cycled all the time. Lot's of shallow charges will give you more total hours of use.

    The battery charge controller logic, however, does need to see the battery fully discharged (all the way to shut off) and fully charged (including being "topped off" maybe an hour or two beyond the full charge indication), at least one to three times, to be calibrate itself accurately. This probably needs to be done only as the battery changes when it ages (maybe only once or twice the first year, after initial calibration - not monthly, as some sources say).

    So my personal rule is: Fully deep charge and discharge once or twice when the unit is brand new. Then try to keep the battery topped off as much as possible for the rest of the life of the product. Recalibrate a year or so later when the battery seems to feel like it's aging or changing characteristics.
  15. razorianfly macrumors 65816


    Oct 16, 2007
    Cheshire, United Kingdom
  16. _Refurbished_ thread starter macrumors 68000


    Mar 23, 2007
    There was no doubt in my mind that this part of the post would get the most attention. I've read about all the other methods that have been brought up so far, but to be on the safe side, I decided to post it this way. As time goes on, we can identify minor issues with the method, so it's perfect. As of right now, I understand people who say you should let your battery drain all the way, but I'm going to keep it the way it is for the time being. If we can get an Apple stamp of approval, or a concrete link proving otherwise, I'll modify the post. Either way, the method originally posted can only do good, not bad :).
  17. HFU macrumors regular

    Jun 8, 2005
    Very informative thread!

    I found the following made noticeable difference on battery life:

    1. Turn off Location Services (GPS) when not using it.
    2. Turn Push to Fetch if you do not expect to receive emails instantly.
    3. Recalibrate battery a few times for new unit for optimal result.
  18. eddiec312 macrumors 6502


    Jul 19, 2008
    Miami, FL
    Why does it say to not use the computer as a charger?

    What's wrong with using the computer over the electric one?
  19. alFR macrumors 68020

    Aug 10, 2006
    Unfortunately your graph doesn't support what you say in the text, as on the graph the iphone browses for longer on EDGE than 3G but you tell us to use 3G rather than EDGE. Care to clarify?
  20. _Refurbished_ thread starter macrumors 68000


    Mar 23, 2007
    Few things. I can't remember my source, but I can remember reading that USB power isn't as consistent as a wall charge. If anyone has a source, that would be great. Can't seem to find it. If we can find a good source that states that USB charging is as good as a wall charge, I'll edit.

    Secondly, if you're computer goes to sleep, your iPhone won't charge.

    I did clarify. The graph was to show what I was clarifying heh.

    "Again, use WiFi for browsing instead of 3G OR EDGE. Otherwise, use 3G instead of EDGE. EDGE doesn't save battery power. Due to the increased amount of time EDGE takes to access a web page, you will actually use up more power with EDGE, than 3G. Complicated sentence made simple: 3G > EDGE for web browsing. EDGE > 3G for voice calls. Hopefully, Apple will release a software update has the option for your phone to set this automatically, but until then, we'll have to do it manually."

    If you want to break it down even further, you get about 2x the speed with 3G over EDGE. Simple math means that if you browse the same amount of sites with EDGE, as you do with 3G, you'll need to be using your iPhone for about twice as long. If you look at the graph, you'll see that the difference in battery life is not 2x as long with EDGE, you're only saving about 40 minutes. Get it?

    I'm thinking I should make an equation so people can see how it works. I was hoping the graph would solve that :).
  21. btr57 macrumors newbie

    Jul 20, 2008
    I have a car charger that is apparently made for iPhones, iPods and other phones, PDAs, etc. When I checked its specs, I noticed it reads as 5V output with <3000 mA. My concern is this is outputting 3A but the wall charger for the iPhone only outputs 1A. Will this car charger fry my new 3G iPhone if I use it?
  22. TB07-NJ macrumors 68020

    Jul 7, 2008
    It's a Lithium Polymer battery not a Lithium Ion battery.
  23. TB07-NJ macrumors 68020

    Jul 7, 2008
    LOL, reading Apple's battery FAQ basically states "turn every feature off" to save battery life. That's great. They should rename it the "offPhone" instead of the "iPhone."
  24. mikef07 macrumors 6502

    Aug 8, 2007
    I get it. For example (Using made up numbers):

    400 Random web pages that you may view take 197 minutes (1 per 30 seconds) on 3G so you could view all of them according to the graph. Those same 400 pages would take 394 minutes (1 per minute) on edge, therefore you would not be able to browse all 400 pages, but only get through ~240 pages or so.
  25. _Refurbished_ thread starter macrumors 68000


    Mar 23, 2007
    Actually, Lithium-Ion Polymer, if we want to get technical :).

    Yea, I personally don't turn off all those features. I usually leave even 3G on all day, as long as my battery last the whole day. Later in the day, if my battery is dying, I'll disable a few battery killing features like 3G / WiFi. Otherwise, my settings are as follows for normal use:

    3G - On
    WiFi - On
    Bluetooth - On
    Location Services - Off
    Bluetooth - On
    Brightness - 50% w/ Auto Brightness

    As long as my battery lasts me the entire day, I'm content with using those settings. This guide is not specifically stating to turn off everything, rather, it's here to give users a source of information to see why and if they should disable a specific setting. Everyone uses their iPhone for different things, so everyone should have different settings.

    As the battery deteriorates, I will probably have to adjust some of my current settings, which is why I am very closely monitoring my charging habits and charge cycles to preserve the battery.


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