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If your iPhone is slow, try replacing the battery

405 points by EduardoBautista 9y ago

digi_owl 9y ago
Makes a guy lament the loss of removable batteries because marketing is all about thin phones...
moonka 9y ago
Very interesting train of thought. Kind of an expensive thing to try if it fails though.
- ericabiz 9y ago
  Shouldn’t be very expensive. I run a chain of independent repair shops — most iPhone batteries are $49-$59 to replace and take about 20 minutes. Apple Store charges $79 for most iPhones.
  - w-ll 9y ago
    A friend of mine went to a repair shop to fix their battery, it was half the cost of Apples repair. But the issues that ensues were whenever they went to speaker phone massive amounts of static seamed to be sent to the mic. If you where on the other end of the call it would be very annoying. To the point we joked about being 'Brain Hacked' Mobile phones have vastly changed in the last few years from once you could replace a battery very easily, to today where it seams you needing $100k equipment to do it properly. My current phone is the 6 SE which up till the last few months has been able to give me a solid 48hrs on a charge, but I've been diligent with making sure I get a full battery cycle. Coupled with no touch ID and only face ID on iphones im a little lost. The pixel doesn't seam like its for me. Maybe I will go back to Motorola, at least they have new expansion slots which remind me of my Compaq Windows CE phone with a PCIe slot. I don't know what im going to do when it starts to crap out. I'm gonna give an official battery replacement a try before I buy something new. But still I feel we have peaked and are tracing back down in mobile phone quality.
    - jonknee 9y ago
      > I don't know what im going to do when it starts to crap out. I'm gonna give an official battery replacement a try before I buy something new. You could just buy another SE, they haven't gone anywhere...
      - w-ll 9y ago
        Yea I could. I hear rumors of a new CE coming out. I feel like I can deal for another 6 months and pray we get an 8 SE. But still official repair vs buying new is a big difference in price.
    - starky 9y ago
      >but I've been diligent with making sure I get a full battery cycle Do you mean that you ensure that the battery fully discharges down to zero every time? Because if so, that is one of the worst things an average consumer can do to a Li-ion or Li-poly cell over the long term life of their device.
      - w-ll 9y ago
        Im not an EE but i've always heard that full battery cycles are best to preserve its life. If not going from 100% to 0% and then charging fully to 100% is the best behavior please inform me.
        wtallis 9y ago
        Fully discharging a battery was only necessary with nickel-cadmium cells that suffered from a severe memory effect. Nickel metal hydride cells didn't, but could be affected reversibly by a minor drop in voltage from repeated partial discharges. Most rechargeable battery technologies in use today are significantly harmed or completely destroyed by a complete discharge. Devices using lithium ion cells all turn themselves off long before the cell is completely empty, as a protective measure.
        w-ll 9y ago
  - matt_wulfeck 9y ago
    How do you know when it’s time to replace the battery?
    - randcraw 9y ago
      The free app "Battery Life" will report the percentage loss of your battery and advise how soon yours needs replacement. It reported that my 5S has lost 39% of its life and should be replaced immediately. The phone works fine, but loses all its charge in 48 hours, even if it isn't used. BTW, Linpack (free app) reports the same speed score when connected to the battery charger vs not, so obviously iOS isn't throttling due to its weak battery.
revelation 9y ago
How do they even detect that? Monitoring voltage drop on current spikes to determine internal resistance? I had a phone with a faulty battery and it would simply turn off on a large current spike (think camera with flash taking a picture) presumably since the voltage crashed.
- rz2k 9y ago
  The device could track the battery's capacity pretty reliably by measuring inputs during charging and outputs during use. The necessary data is even available to third party apps on both iOS and MacOS (Battery Life, and Battery Health are two examples) It sounds like the idea is that the OS is throttling the performance to extend the battery life of a battery in poor condition, more than it sounds like it is limiting current draw to avoid "brownouts". I can see why this is a good idea and a bad idea, in that many people simply want a full day of being reachable on the phone more than they want smartphone features, but others who are considering replacement would like to know that a $100 fix would make their phone less frustrating.
- starky 9y ago
  It is pretty simple to figure out the capacity by monitoring cell voltage and discharge current over time. Monitoring the impedance would be an additional bit of data that would correlate to the health of the materials in the cell, but is neither the easiest, nor the most accurate way of monitoring cell health.
- jmiller099 9y ago
  Here's some info from a jailbroken ipad (redacted some unique identifiers): iPad:~/ root# ioreg -l -w0 | grep Capacity | | | | | "Capacity" = 960 | | "BootCapacityEstimate" = 87 | | "BatteryData" = {"CycleCount"=232,"MaxCapacity"=10639,"FullAvailableCapacity"=11085,"StateOfCharge"=98, "MfgData"=<redacted cuz it looks like a unique id>, "DesignCapacity"=11560,"QmaxCell0"=11678,"Flags"=1,"ManufactureDate"="6205","ChemID"=4384,"BatterySerialNumber"="redacted","Voltage"=4155} | | "CurrentCapacity" = 10500 | | "BootBBCapacity" = 10364 | | "AppleRawCurrentCapacity" = 10242 | | "AbsoluteCapacity" = 11272 | | "AppleRawMaxCapacity" = 10489 | | "MaxCapacity" = 10500 | | "DesignCapacity" = 11560 I hypothesize that the MaxCapacity will drift lower over time. They have all the info they need in their registry.
shasheene 9y ago
There's a decades-long meme that Apple purposefully slows down older hardware to push people to buy completely new hardware. Interesting that this effect may be a byproduct of automatic scaling the CPU frequency based on remaining battery capacity, rather than the newer OS versions being purposefully poorly optimized (like most people assume)
- wtallis 9y ago
  > There's a decades-long meme that Apple purposefully slows down older hardware to push people to buy completely new hardware. I seem to recall the first several years—maybe even the first decade—of OS X being marked by each new release being faster on the same hardware, though dropping support for the oldest hardware. It was definitely true for the first few releases of OX X, because 10.0 was notoriously sluggish. I also don't recall any slowdowns with my 2006 iMac across the several upgrades it received before Apple made 64-bit firmware a hard requirement. If there's any truth to the meme you cite, it probably stems from the mobile side of things, where iOS started out fairly efficient but the hardware was very underpowered. (And in that case, I'd like to point out that the iPhone is only 10.5 years old.)
  - Washuu 9y ago
    Entirely the mobile side of things due to upgrading iOS. I was forced to upgrade from iOS 10 to 11 on my iPhone 6 to be allowed to use two factor authentication for my work place. Instantly it become a sluggish mess.
  - alanfalcon 9y ago
    At that point Apple sold the OS upgrades, though, and now they only make money on the hardware (well, and services etc., but not on OS sales). So it makes sense that things have changes as their incentives have realigned, in addition to the factors you cite.
    - lparry 9y ago
      Apple has never sold updates for iPhones. What you’re misremembering is them selling updates for iPod touches back at iOS 2 because of some perceived accounting issue, and the cost was pretty token, something like $5-10 IIRC correctly. Hardly a cash cow that would have had them making more optimisations then they do today
givinguflac 9y ago
This is certainly a solid correlation, but I’d want to see the same device with the old battery again (or even better another device of the same model) to prove that is the cause. Disconnecting the battery resets things that aren’t reset by other methods.
- dannyw 9y ago
  iOS 10.2.1 “fixed” the sudden shutdown issues by dynamically scaling clock speed based on battery wear, and capacity. It would be good to verify the former in a controlled environment. The latter is easily verified by Geekbenching your iPhone every 10% it drops.
- SkyPuncher 9y ago
  Reddit OP made an edit indicating he tested the old battery again and found the same results.
qd6pwu4 9y ago
Last week, I replaced the battery for my iPhone6s, because the old battery has almost died. After that, it becomes much faster than before. The old battery often shuts down even though there is 50% left. My phone is on the recall list but I can never book a slot for replacing the battery in any Apple store here in Hangzhou, China. They are always full. Very disappointed with Apple's service. Then I bought a third-party battery on Taobao for less than 20$ and replaced it by myself. When my phone turns on again, I feel it's so fast and smooth. Then I realized iphone drops cpu frequency when battery dies. The new battery is 2200mAh, 550mAh larger than original. Now my phone can last a whole day under normal use.
- limeblack 9y ago
  Do Apple Stores work differently in China? In the United States I have been able to call about a week out and get devices serviced in the past.
  - qd6pwu4 9y ago
    I went to the Apple store, they will only replace battery for me after I book a slot on the Internet. But I can never successfully do that.
    - limeblack 9y ago
      So you don't have internet or their website doesn't work? Maybe there are no times available?
      - qd6pwu4 9y ago
        Their website always says no times available.
- pixelcloud 9y ago
  I wonder if Android does the same thing. My understanding if batteries is that @ 100% charge they are going to sit around a certain voltage. They will never stay at the maximum voltage under use though. Is it possible that the OS needs to drop the CPU freq due to the voltage requirements (which maybe a 70% healthy battery could NEVER hit), and ultimately stressing/draining the battery quicker at higher frequencies.
lwansbrough 9y ago
I bought my iPhone 2 years ago (iPhone 6, new) -- it's since been plagued by slowdowns that are incomprehensible to me as a software developer. How can something go from completely responsive to absolutely useless in 2 years with virtually no major changes to the OS? Scaling the CPU down with battery capacity seems like a great way to hand-wave away planned obsolescence accusations. I was curious about the results my phone would receive, so I bought the Geekbench app mentioned in the reddit post. Indeed, my phone scores max out at half of what it claims the iPhone 6 should benchmark at. I'm pissed.
- EduardoBautista 9y ago
  On the other hand, people would complain about the horrible battery life. In any case, the solution is rather simple: just replace the battery.
  - modeless 9y ago
    If the battery is so small that it can't last 2 years of normal wear without becoming "horrible", the design is bad. Papering over the bad design by making the phone run at less than 60% of rated speed, on purpose, is even worse. Battery wear is expected, but it is not reasonable to expect that the CPU will be affected too, and this has never been disclosed AFAIK. Also, replacing a non-user-replaceable battery is not a "simple" solution.
    - threeseed 9y ago
      (1) All batteries degrade. Really not sure why you think Apple would be any different. (2) Replacing the battery is simple. You take it to a phone shop or to Apple and in about an hour it is done. Most people aren't self servicing electronics or pretty much anything these days.
      - modeless 9y ago
        > not sure why you think Apple would be any different. I don't and my comment doesn't suggest that. What I suggest is that phones with non-user-replaceable batteries should be designed with capacity large enough so that life is still acceptable after two years of normal wear without throttling the CPU. As for how "simple" replacing the battery is, I don't consider a $79 repair that requires an appointment and driving to an Apple Store and wasting an hour of my day "simple".
abakker 9y ago
So, does this not show up when the phone is plugged in? If the iPhone is plugged in, does it still throttle the CPU?
- clishem 9y ago
  My grandmothers iPad 3 has become completely unusable because of throtteling, whether is is plugged in or not.
- dannyw 9y ago
  iOS does not adjust battery-related throttling (whether low battery, low power mode, or battery wear) based on if it is charging. Same as recent macs. So yes.
  - abakker 9y ago
    Thanks - that is really interesting. So Apple designed the system in a way that definitely hides deteriorating performance due to throttling from the end user? Can you point to any documentation that validates this?
    - dannyw 9y ago
      Apple doesn’t officially document that, but see various support discussions: https://discussions.apple.com/thread/4468165 https://discussions.apple.com/thread/4468165
  - gaadd33 9y ago
    Why do recent macs throttle based on battery? I don't think my iMac has a battery to replace?
woopsie111 9y ago
Can you imagine the number of devices that get needlessly replaced because of this? Talk about taking planned obsolescence to the next level. Battery wear is as certain as death and taxes in a mobile device, and this feature converts obvious battery wear into ambiguous device wear. I would not be surprised if this were class action lawsuit material.
- isoprophlex 9y ago
  I did some googling and the level of public outrage at this seems to be very low! Given the shit storm after they dropped the headphone jack I expected more of a reaction to this news... Maybe news outlets haven't picked it up yet?
  - arvinsim 9y ago
    One word: Shareholders.
terminalcommand 9y ago
After a while my iPhone 5 battery started swelling. It swell so much that the screen popped out. I took it to an Apple Store, paid the fee and got a refurbished new one. With iOS 10 it's really responsive. The only complaint I could make is about storage. In the age of spotify and bloated applications, living with 16G of storage is not pleasant.
- drawkbox 9y ago
  I have lots of devices for testing apps/games and four 5/5s generation iPhones/iPods. All of them did the same lithuim-ion/swelling with the battery within 2-3 months where the screen pops out and you can see inside on the edges. This is heavily common and prevalent with that generation I found out. iPhones/iPods both had it happen. It was a little bit twilight zone like before I looked into how common it is, bought them at different times. If you aren't constantly using a device turn it off because LiB batteries they use only last about 2 years / 400 charges and overcharging ends up swelling.
  - terminalcommand 9y ago
    Thanks for the notice, I didn't know about it. Unfortunately iPhone 5 is my primary phone so I use it daily. I was always charging the phone with a 2A charger back then, now I switched to 1A. I thought maybe slow charging will help preserve the battery. Anyways 2 years is a reasonable time for me considering the age of my phone, after 2 years I'll probably switch to a new phone.
  - gaadd33 9y ago
    400 charges would be a little bit more than 1 year for most people. Do you have any links that show most cell phone batteries only last that long?
    - deleted 9y ago
      [deleted]
    - drawkbox 9y ago
      There are lots of articles on it but here is one from 6S/7 regarding 300-400 cycles [1]. You can look for Apple battery swelling and nearly every gen since 5 has some issues with it, it seems related to overcharging. Even iPhone 8 is having issues with swelling. [2] [1] http://bgr.com/2016/11/30/iphone-7-vs-iphone-6s-battery-drain/ http://bgr.com/2016/11/30/iphone-7-vs-iphone-6s-battery-drai... [2] https://www.macrumors.com/2017/10/01/apple-looking-into-iphone-8-battery-failures/ https://www.macrumors.com/2017/10/01/apple-looking-into-ipho...
olalonde 9y ago
Just replaced the battery on an old MacBook Air and it feels 10x faster (even when it's connected to the power adapter).
joelthelion 9y ago
I wonder if Android has something similar?
askvictor 9y ago
Curious if this is the case on iPads too (can't see any reason why it wouldn't). I have a lot of iPad 2's at work, and they definitely get slower with age. OS upgrades are a bit problem; after iOS 6 (I think) performance decreased very noticeably (and I have the luxury of being able to compare side by side with other units). But recently the unit I've been using with ios6 has started to slow considerably. I figured that it's an ageing flash memory issue, but this is another contender.
milankragujevic 9y ago
I'd actually be comfortable claiming that everyone's slow iPhones are actually faulty. Because mine (5S) was really slow and not even a clean reinstall would help, and I went to the support service for my carrier and they sent it for service and after a few days sent back a new iPhone because the old one was broken. The new one was much faster even thought it was the same model, and had the same OS version. So, people, get it checked out, it might be faulty, for example the NAND flash memory might wear out or the base firmware might've been corrupted, or hey, the battery might be bad...
napsterbr 9y ago
Let me share one experience that was neither a battery problem nor a faulty iPhone. After my iPhone 6 (ios 10) got stolen, I've bought a brand new iPhone 6s (ios 11) on the official apple store. It was totally unusable, all problems people shared I've had as well. It would take several seconds for an app to open, the phone would freeze for one minute, volume controls on the lock screen wouldn't work, my Bluetooth range was literally less than 10cm, sometimes when I called the phone would mute my voice. I've tried resetting the phone twice. No luck. Then I've downgraded to iOS 10 and all problems went away; performance was similar to my previous phone. So, no battery problem, no buggy phone, just a very very buggy operating system (or an OS that purposefully slows down on older devices).
ant6n 9y ago
Knowing the issues with fixed in batteries these day, I purchased myself an LG G3, one of the few good smartphones with a replaceable battery. The idea is that once it goes bad, it'll be a simple switch. The problem nowadays is that it's almost impossible to get an original battery. On Amazon, everything is a fake. In stores, the battery does not exist anymore or is super expensive. It seems LG doesn't care, maybe they speculate people will just buy new phones. In a way, my approach to have replaceable batteries failed.
- jjawssd 9y ago
  ZeroLemon batteries have worked well for me for the last 3 years. I now use a gigantic 10,000 mAh battery with included custom back plate for my phone.
b212 9y ago
Does it affect only 6(S)? I'm thinking about getting SE as I have small hands and it looks like a perfect fit but I think it's kind of pointless to get a new iPhone with so serious, known and most likely impossible to fix, bug? SE is expensive to me as it is, I don't want to replace battery every year or so (I'm a heavy user).
- dade_ 9y ago
  I have an SE, nearly 2 years old and I didn’t notice any difference in performance with iOS 11, only improvements in the UI. Definately nothing as described by iPhone 6 owners which makes me think this is specific to certain devices.
- lucaspiller 9y ago
  Both my wife and I have three year old 5Ss, but our experience with iOS 11 has been completely different. For me it works just as well as 10, maybe even slightly better. For her it has turned her phone into a complete dog, even opening a contact in Messages takes seconds. Recently her battery has started to show signs that it is wearing out, such as jumping instantly from 5% to 30% when plugging it in to charge, so it looks like this behaviour is a software 'feature' on all iPhones.
- graeme 9y ago
  I have a five month old SE, works great. None of the issues which plague my friend's 6s. Can't comment on long run performance. I can say I've never heard it mentioned in these threads. I'd google SE battery throttling specifically though.
htsh 9y ago
One tangential weird experience: My iPhone 6s plus battery went obviously bad, as in reduced battery life and really big jumps down from 100 -> 70 and then from 40 -> 10 from minimal use. After months of dealing with the bad battery, hooking it up to my mac & running Coconut battery showed it was 46% good. So I took it to the store for an official replacement (I decided I would pay for it). The genius ran a diagnostic which showed the battery as fine (green, he called it) and almost immediately started to tell me why it may be something else in the phone and started pointing me towards buying another phone instead of getting the battery replaced. But for some reason their diag tool is worse than coconut battery or just wrong? If my battery were 60-70% good and they had lowered thresholds that's one thing, but my battery was long gone and they told me it's fine. And of course I insisted and the phone is fine now with a new battery. I know there's probably a decent explanation for it but it certainly felt like they really wanted me to buy a new phone, and that their diag tool perhaps isn't the most truthful right now when it comes to battery health.
- epicide 9y ago
  The 6S's had a bad batch or two. You might want to check if your serial number falls into that range: https://www.apple.com/support/iphone6s-unexpectedshutdown/ https://www.apple.com/support/iphone6s-unexpectedshutdown/
  - htsh 9y ago
    Yup, I did and mine was fine. I mean I used the hell out of the phone since it came out and I knew the battery was bad just based on the cycle count and my heavy usage. I believe the tech checked as well right when I brought it in. What was weird was they told me the battery was fine and something else was wrong. And the phone has been fine since the replacement. And I think coconut is pretty reliable. We ran it on a couple of coworker phones before bringing my phone in, and mine was by far the lowest. Everyone was up in the 80s and mine was in the 40s. It ran multiple times with the same result. The apple tech told me green means it's in the 80s.
- gargravarr 9y ago
  Very nice tie-in to the planned-obsolescence theme others are throwing around - Apple would much rather push you towards buying a new phone (and because of their advertising, their target market would probably accept their reasoning) while a simpler option exists that won't make them nearly as much money.
waffl 9y ago
I replaced an aging battery on my 6S Plus a few months ago myself and installed iOS 11 at the same time (figured it was a good opportunity to do both together). Immediately I noticed my phone was basically unusable, incredibly slow, everything was crashing or locking up completely, I couldn’t believe it. I thought iOS 11 was the culprit, and even did a complete reinstall without restoring any backups to no avail. Finally, I noticed a slight dark spot on the LCD - the brand new battery I had bought was already bulging and in bad shape. I sprung for a better quality battery from ifixit and immediately the phone was running like brand new again. I thought the cheap battery had been supplying an unstable current, but perhaps there is indeed an issue with the software itself. One key thing I realized - ANY battery work done outside of Apple’s official repair means they will never work on your phone again. So if you care about having Apple do any kind of work on your phone (even if totally unrelated to battery), you will have to get it replaced by them.
- Synaesthesia 9y ago
  It’s very hard to get quality batteries outside of Apple which kind of sucks for iPhone repair. Yeah the 3rd party ones usually suck.
  - waffl 9y ago
    Actually I feel almost any component in general sadly. I had to replace the front camera assembly as well and after trying almost four different parts from multiple vendors and none match the quality of the original. Another thing I learned is that Apple would replace the entire display and front assembly (front camera, earpiece, speaker, brightness sensor, proximity sensor) for only ~ $150. However, due to the third party battery they couldn’t work on it anymore.
    - Synaesthesia 9y ago
      Yeah the displays and touch panels are also sometimes inferior. That’s a real shame about your phone sorry.
  - jakobegger 9y ago
ComputerGuru 9y ago
I bought an 8+ over an 8 hopping typing would be more accurate and faster on the larger screen (it’s not) thinking I would return it in the “no questions asked” period if not, but stayed for the incredible battery life. Before this, I had forgotten what it was like to be able to use your phone all day even after forgetting to plug it in the night before. Apple can make batteries that have awesome run times - they just choose not to so the phone can be x% slimmer. Bummer.
ComputerGuru 9y ago
So what’s the rationale for poor performance even when plugged in?
johnflan 9y ago
If that were true, wouldn't plugging in the phone alleviate the problem (while plugged in)
- gargravarr 9y ago
  See other comments. iOS appears to ignore the charger state and scale frequency based purely on the battery capacity.
overcast 9y ago
Damn my 6S is doing exactly this, loaded up CPU DasherX and it's showing it at 1200mhz instead of 1848mhz the 6S is supposed to be at. Just setup a service through Apple at the local BestBuy in an hour. Thanks!
fma 9y ago
I found a more permanent solution. Instead of replacing it with a new battery, I replaced it with a Samsung S8. There are some things I miss about the iPhone, and maybe I'll consider it again in the future..but after 3 iterations of iPhones I got off the hype train when "it just works" became "it just doesn't work". I also had issues with backups and lost data... My wife got the iPhone X (yes...I know, $1000) and she's encountered a few bugs/crashes. I make fun of her for it. I find the usability of my Samsung not as good as iPhone when iPhone was at the peak, but I'm ok with it beacuse I'm not buying a device that touts itself as 'it just works'...plus I got it for 1/3rd the price after massive discounts.
- jonny_eh 9y ago
  Are you saying that Samsung phone batteries don't go bad over time?
  - bparsons 9y ago
    I think the issue here is CPU performance being tied to battery degradation as a method of planned obsolescence, rather than a complaint about iPhone battery life.
    - Retric 9y ago
      It's not really planned obsolescence, they made the trade off of CPU speed instead of battery life when the battery gets old. This is more reasonable than you might think as deep discharges use up batterie life faster. The other option is for the phone to not keep it's charge for nearly as long which would likely be more annoying. In either case it's a ~40$ repair to replace a phones battery and IMO a good idea at ~2-3 years old on all phones. Assuming you keep your phone for 4-5 years.
  - fma 9y ago
    I'm saying I've invested a lot of money in a platform that touts itself as the best and user friendly. My recent personal experiences has shown that it is not. Hence, I refuse to pay the luxury tax on an item that does not provide me a good experience. Their tagline is "it just does". Sorry, no, it doesn't. I saved ~$500 when purchasing the flagship phone of another platform, so even if the experience is poor, I have an extra $500 in the bank. Also - the Samsung S8 gives you very fine control on throttling the CPU to save power.
opensports 9y ago
The title should be "If your iPhone or MacBook is slow, try replacing the battery." My MacBook Pro became so slow that I spent days trying to figure out why, only to discover it was my bad battery.
- ak39 9y ago
  Thanks for this. Would you know whether boot camp windows would also be affected by this?
  - opensports 9y ago
    From what I've read I'm fairly certain it is not affected.
oger 9y ago
Had massive issues with my 6s during the last weeks. Upgrading to 11.2 significantly improved the laggy behaviour issue. However the Geekbench 4 results are interesting. Benchmark numbers for my iPhone 6S: Compute: 5551 / Multi-Core: 1732 / Single Core: 1045 versus "normal" 6S Benchmark numbers (taken from the app): Compute 10143 / Multi-Core: 3994 / Single Core: 2376. In summary my iPhone 6s is SIGNIFICANTLY (~2x) underperforming in this benchmark to where a "normal" 6s should be. How trustworthy are the benchmark figures in the app? Any other ideas? For the time being this seems to justify the suspicions.
SkyPuncher 9y ago
I wonder if any consumer protection laws will come into place. Particularly, those in the EU. While I see any argument for Apple doing this (helps keep the battery life high), this is not a disclosed feature. It's intentionally limiting the product's capabilities from what's marketed. People expect batteries to become worse with time - there is no getting around the fact that the chemical reaction becomes worse with use. A CPU, though, that should never see significant scaleback unless it's faulty.
- jakobegger 9y ago
  CPU running at max speed requires a lot of power. Degraded batteries have a higher internal resistance, which lowers the amount of power they can provide. So when the CPU draws a lot of power, the voltage on the battery drops. If the voltage drops to low, the battery protection circuit will shut it off. What people here don’t seem to understand is that capacity, battery health, and max power output are related. Old batteries just can’t provide the current that the phone needs. Battery replacements are cheap, and when your battery is degraded you should just swap it. Consumer protection laws won’t help you here. Apple is not pretending to sell a phone that doesn’t need service; on the contrary, they even strongly advertise their “protection plan” that would cover degraded batteries.
  - GordonS 9y ago
    I think the biggest issue here is that your phone will do this silently. I think a better solution would be to notify the user and ask them if they want to go into the reduced power mode. I have an S7, and when the battery level gets really low it does exactly that (although it can actually take it even further if you want, switching off the radio, making the display monochrome etc).
    - jakobegger 9y ago
      Low power mode is something different, and iOS has that too. The problem here isn't that iOS isn't just trying to conserve power to last a bit longer. At some point the battery physically can't deliver the current required to run the CPU at max speed. At that point, the phone battery settings screen says something like "Battery Service Required". For some reason a lot of people get annoyed when their phone needs service. It's understandable, but I really don't see what Apple should do about it. When a car's battery needs to be replaced, people don't go complaining how their car is suffering from planned obsolescence, they just replace the battery.
alliao 9y ago
I used the AnTuTu benchmark app as I am cheap... and I found out my IO have scored lowly. Turns out having only a few hundred megabytes hinders the performance a great deal. After wiping 3GB of photos and videos the phone's gone back to it's snappy self. Though I'm still on iOS 10.3 or so...
punnerud 9y ago
It works! Replaced my battery now after this post and my score went from 810 to 1455, with a huge noticeable performance improvement and lower app loading time.

digi_owl 9y ago

Makes a guy lament the loss of removable batteries because marketing is all about thin phones...

moonka 9y ago

Very interesting train of thought. Kind of an expensive thing to try if it fails though.

ericabiz 9y ago
Shouldn’t be very expensive. I run a chain of independent repair shops — most iPhone batteries are $49-$59 to replace and take about 20 minutes. Apple Store charges $79 for most iPhones.
- w-ll 9y ago
  A friend of mine went to a repair shop to fix their battery, it was half the cost of Apples repair. But the issues that ensues were whenever they went to speaker phone massive amounts of static seamed to be sent to the mic. If you where on the other end of the call it would be very annoying. To the point we joked about being 'Brain Hacked' Mobile phones have vastly changed in the last few years from once you could replace a battery very easily, to today where it seams you needing $100k equipment to do it properly. My current phone is the 6 SE which up till the last few months has been able to give me a solid 48hrs on a charge, but I've been diligent with making sure I get a full battery cycle. Coupled with no touch ID and only face ID on iphones im a little lost. The pixel doesn't seam like its for me. Maybe I will go back to Motorola, at least they have new expansion slots which remind me of my Compaq Windows CE phone with a PCIe slot. I don't know what im going to do when it starts to crap out. I'm gonna give an official battery replacement a try before I buy something new. But still I feel we have peaked and are tracing back down in mobile phone quality.
  - jonknee 9y ago
    > I don't know what im going to do when it starts to crap out. I'm gonna give an official battery replacement a try before I buy something new. You could just buy another SE, they haven't gone anywhere...
    - w-ll 9y ago
      Yea I could. I hear rumors of a new CE coming out. I feel like I can deal for another 6 months and pray we get an 8 SE. But still official repair vs buying new is a big difference in price.
  - starky 9y ago
    >but I've been diligent with making sure I get a full battery cycle Do you mean that you ensure that the battery fully discharges down to zero every time? Because if so, that is one of the worst things an average consumer can do to a Li-ion or Li-poly cell over the long term life of their device.
    - w-ll 9y ago
      Im not an EE but i've always heard that full battery cycles are best to preserve its life. If not going from 100% to 0% and then charging fully to 100% is the best behavior please inform me.
      - wtallis 9y ago
        Fully discharging a battery was only necessary with nickel-cadmium cells that suffered from a severe memory effect. Nickel metal hydride cells didn't, but could be affected reversibly by a minor drop in voltage from repeated partial discharges. Most rechargeable battery technologies in use today are significantly harmed or completely destroyed by a complete discharge. Devices using lithium ion cells all turn themselves off long before the cell is completely empty, as a protective measure.
        w-ll 9y ago
- matt_wulfeck 9y ago
  How do you know when it’s time to replace the battery?
  - randcraw 9y ago
    The free app "Battery Life" will report the percentage loss of your battery and advise how soon yours needs replacement. It reported that my 5S has lost 39% of its life and should be replaced immediately. The phone works fine, but loses all its charge in 48 hours, even if it isn't used. BTW, Linpack (free app) reports the same speed score when connected to the battery charger vs not, so obviously iOS isn't throttling due to its weak battery.

revelation 9y ago

How do they even detect that? Monitoring voltage drop on current spikes to determine internal resistance? I had a phone with a faulty battery and it would simply turn off on a large current spike (think camera with flash taking a picture) presumably since the voltage crashed.

rz2k 9y ago
The device could track the battery's capacity pretty reliably by measuring inputs during charging and outputs during use. The necessary data is even available to third party apps on both iOS and MacOS (Battery Life, and Battery Health are two examples) It sounds like the idea is that the OS is throttling the performance to extend the battery life of a battery in poor condition, more than it sounds like it is limiting current draw to avoid "brownouts". I can see why this is a good idea and a bad idea, in that many people simply want a full day of being reachable on the phone more than they want smartphone features, but others who are considering replacement would like to know that a $100 fix would make their phone less frustrating.
starky 9y ago
It is pretty simple to figure out the capacity by monitoring cell voltage and discharge current over time. Monitoring the impedance would be an additional bit of data that would correlate to the health of the materials in the cell, but is neither the easiest, nor the most accurate way of monitoring cell health.
jmiller099 9y ago
Here's some info from a jailbroken ipad (redacted some unique identifiers): iPad:~/ root# ioreg -l -w0 | grep Capacity | | | | | "Capacity" = 960 | | "BootCapacityEstimate" = 87 | | "BatteryData" = {"CycleCount"=232,"MaxCapacity"=10639,"FullAvailableCapacity"=11085,"StateOfCharge"=98, "MfgData"=<redacted cuz it looks like a unique id>, "DesignCapacity"=11560,"QmaxCell0"=11678,"Flags"=1,"ManufactureDate"="6205","ChemID"=4384,"BatterySerialNumber"="redacted","Voltage"=4155} | | "CurrentCapacity" = 10500 | | "BootBBCapacity" = 10364 | | "AppleRawCurrentCapacity" = 10242 | | "AbsoluteCapacity" = 11272 | | "AppleRawMaxCapacity" = 10489 | | "MaxCapacity" = 10500 | | "DesignCapacity" = 11560 I hypothesize that the MaxCapacity will drift lower over time. They have all the info they need in their registry.

shasheene 9y ago

There's a decades-long meme that Apple purposefully slows down older hardware to push people to buy completely new hardware. Interesting that this effect may be a byproduct of automatic scaling the CPU frequency based on remaining battery capacity, rather than the newer OS versions being purposefully poorly optimized (like most people assume)

wtallis 9y ago
> There's a decades-long meme that Apple purposefully slows down older hardware to push people to buy completely new hardware. I seem to recall the first several years—maybe even the first decade—of OS X being marked by each new release being faster on the same hardware, though dropping support for the oldest hardware. It was definitely true for the first few releases of OX X, because 10.0 was notoriously sluggish. I also don't recall any slowdowns with my 2006 iMac across the several upgrades it received before Apple made 64-bit firmware a hard requirement. If there's any truth to the meme you cite, it probably stems from the mobile side of things, where iOS started out fairly efficient but the hardware was very underpowered. (And in that case, I'd like to point out that the iPhone is only 10.5 years old.)
- Washuu 9y ago
  Entirely the mobile side of things due to upgrading iOS. I was forced to upgrade from iOS 10 to 11 on my iPhone 6 to be allowed to use two factor authentication for my work place. Instantly it become a sluggish mess.
- alanfalcon 9y ago
  At that point Apple sold the OS upgrades, though, and now they only make money on the hardware (well, and services etc., but not on OS sales). So it makes sense that things have changes as their incentives have realigned, in addition to the factors you cite.
  - lparry 9y ago
    Apple has never sold updates for iPhones. What you’re misremembering is them selling updates for iPod touches back at iOS 2 because of some perceived accounting issue, and the cost was pretty token, something like $5-10 IIRC correctly. Hardly a cash cow that would have had them making more optimisations then they do today

givinguflac 9y ago

This is certainly a solid correlation, but I’d want to see the same device with the old battery again (or even better another device of the same model) to prove that is the cause. Disconnecting the battery resets things that aren’t reset by other methods.

dannyw 9y ago
iOS 10.2.1 “fixed” the sudden shutdown issues by dynamically scaling clock speed based on battery wear, and capacity. It would be good to verify the former in a controlled environment. The latter is easily verified by Geekbenching your iPhone every 10% it drops.
SkyPuncher 9y ago
Reddit OP made an edit indicating he tested the old battery again and found the same results.

qd6pwu4 9y ago

Last week, I replaced the battery for my iPhone6s, because the old battery has almost died. After that, it becomes much faster than before. The old battery often shuts down even though there is 50% left. My phone is on the recall list but I can never book a slot for replacing the battery in any Apple store here in Hangzhou, China. They are always full. Very disappointed with Apple's service. Then I bought a third-party battery on Taobao for less than 20$ and replaced it by myself. When my phone turns on again, I feel it's so fast and smooth. Then I realized iphone drops cpu frequency when battery dies. The new battery is 2200mAh, 550mAh larger than original. Now my phone can last a whole day under normal use.

limeblack 9y ago
Do Apple Stores work differently in China? In the United States I have been able to call about a week out and get devices serviced in the past.
- qd6pwu4 9y ago
  I went to the Apple store, they will only replace battery for me after I book a slot on the Internet. But I can never successfully do that.
  - limeblack 9y ago
    So you don't have internet or their website doesn't work? Maybe there are no times available?
    - qd6pwu4 9y ago
      Their website always says no times available.
pixelcloud 9y ago
I wonder if Android does the same thing. My understanding if batteries is that @ 100% charge they are going to sit around a certain voltage. They will never stay at the maximum voltage under use though. Is it possible that the OS needs to drop the CPU freq due to the voltage requirements (which maybe a 70% healthy battery could NEVER hit), and ultimately stressing/draining the battery quicker at higher frequencies.

lwansbrough 9y ago

I bought my iPhone 2 years ago (iPhone 6, new) -- it's since been plagued by slowdowns that are incomprehensible to me as a software developer. How can something go from completely responsive to absolutely useless in 2 years with virtually no major changes to the OS? Scaling the CPU down with battery capacity seems like a great way to hand-wave away planned obsolescence accusations. I was curious about the results my phone would receive, so I bought the Geekbench app mentioned in the reddit post. Indeed, my phone scores max out at half of what it claims the iPhone 6 should benchmark at. I'm pissed.

EduardoBautista 9y ago
On the other hand, people would complain about the horrible battery life. In any case, the solution is rather simple: just replace the battery.
- modeless 9y ago
  If the battery is so small that it can't last 2 years of normal wear without becoming "horrible", the design is bad. Papering over the bad design by making the phone run at less than 60% of rated speed, on purpose, is even worse. Battery wear is expected, but it is not reasonable to expect that the CPU will be affected too, and this has never been disclosed AFAIK. Also, replacing a non-user-replaceable battery is not a "simple" solution.
  - threeseed 9y ago
    (1) All batteries degrade. Really not sure why you think Apple would be any different. (2) Replacing the battery is simple. You take it to a phone shop or to Apple and in about an hour it is done. Most people aren't self servicing electronics or pretty much anything these days.
    - modeless 9y ago
      > not sure why you think Apple would be any different. I don't and my comment doesn't suggest that. What I suggest is that phones with non-user-replaceable batteries should be designed with capacity large enough so that life is still acceptable after two years of normal wear without throttling the CPU. As for how "simple" replacing the battery is, I don't consider a $79 repair that requires an appointment and driving to an Apple Store and wasting an hour of my day "simple".

abakker 9y ago

So, does this not show up when the phone is plugged in? If the iPhone is plugged in, does it still throttle the CPU?

clishem 9y ago
My grandmothers iPad 3 has become completely unusable because of throtteling, whether is is plugged in or not.
dannyw 9y ago
iOS does not adjust battery-related throttling (whether low battery, low power mode, or battery wear) based on if it is charging. Same as recent macs. So yes.
- abakker 9y ago
  Thanks - that is really interesting. So Apple designed the system in a way that definitely hides deteriorating performance due to throttling from the end user? Can you point to any documentation that validates this?
  - dannyw 9y ago
    Apple doesn’t officially document that, but see various support discussions: https://discussions.apple.com/thread/4468165 https://discussions.apple.com/thread/4468165
- gaadd33 9y ago
  Why do recent macs throttle based on battery? I don't think my iMac has a battery to replace?

woopsie111 9y ago

Can you imagine the number of devices that get needlessly replaced because of this? Talk about taking planned obsolescence to the next level. Battery wear is as certain as death and taxes in a mobile device, and this feature converts obvious battery wear into ambiguous device wear. I would not be surprised if this were class action lawsuit material.

isoprophlex 9y ago
I did some googling and the level of public outrage at this seems to be very low! Given the shit storm after they dropped the headphone jack I expected more of a reaction to this news... Maybe news outlets haven't picked it up yet?
- arvinsim 9y ago
  One word: Shareholders.

terminalcommand 9y ago

After a while my iPhone 5 battery started swelling. It swell so much that the screen popped out. I took it to an Apple Store, paid the fee and got a refurbished new one. With iOS 10 it's really responsive. The only complaint I could make is about storage. In the age of spotify and bloated applications, living with 16G of storage is not pleasant.

drawkbox 9y ago
I have lots of devices for testing apps/games and four 5/5s generation iPhones/iPods. All of them did the same lithuim-ion/swelling with the battery within 2-3 months where the screen pops out and you can see inside on the edges. This is heavily common and prevalent with that generation I found out. iPhones/iPods both had it happen. It was a little bit twilight zone like before I looked into how common it is, bought them at different times. If you aren't constantly using a device turn it off because LiB batteries they use only last about 2 years / 400 charges and overcharging ends up swelling.
- terminalcommand 9y ago
  Thanks for the notice, I didn't know about it. Unfortunately iPhone 5 is my primary phone so I use it daily. I was always charging the phone with a 2A charger back then, now I switched to 1A. I thought maybe slow charging will help preserve the battery. Anyways 2 years is a reasonable time for me considering the age of my phone, after 2 years I'll probably switch to a new phone.
- gaadd33 9y ago
  400 charges would be a little bit more than 1 year for most people. Do you have any links that show most cell phone batteries only last that long?
  - deleted 9y ago
    [deleted]
  - drawkbox 9y ago
    There are lots of articles on it but here is one from 6S/7 regarding 300-400 cycles [1]. You can look for Apple battery swelling and nearly every gen since 5 has some issues with it, it seems related to overcharging. Even iPhone 8 is having issues with swelling. [2] [1] http://bgr.com/2016/11/30/iphone-7-vs-iphone-6s-battery-drain/ http://bgr.com/2016/11/30/iphone-7-vs-iphone-6s-battery-drai... [2] https://www.macrumors.com/2017/10/01/apple-looking-into-iphone-8-battery-failures/ https://www.macrumors.com/2017/10/01/apple-looking-into-ipho...

olalonde 9y ago

Just replaced the battery on an old MacBook Air and it feels 10x faster (even when it's connected to the power adapter).

joelthelion 9y ago

I wonder if Android has something similar?

askvictor 9y ago

Curious if this is the case on iPads too (can't see any reason why it wouldn't). I have a lot of iPad 2's at work, and they definitely get slower with age. OS upgrades are a bit problem; after iOS 6 (I think) performance decreased very noticeably (and I have the luxury of being able to compare side by side with other units). But recently the unit I've been using with ios6 has started to slow considerably. I figured that it's an ageing flash memory issue, but this is another contender.

milankragujevic 9y ago

I'd actually be comfortable claiming that everyone's slow iPhones are actually faulty. Because mine (5S) was really slow and not even a clean reinstall would help, and I went to the support service for my carrier and they sent it for service and after a few days sent back a new iPhone because the old one was broken. The new one was much faster even thought it was the same model, and had the same OS version. So, people, get it checked out, it might be faulty, for example the NAND flash memory might wear out or the base firmware might've been corrupted, or hey, the battery might be bad...

napsterbr 9y ago

Let me share one experience that was neither a battery problem nor a faulty iPhone. After my iPhone 6 (ios 10) got stolen, I've bought a brand new iPhone 6s (ios 11) on the official apple store. It was totally unusable, all problems people shared I've had as well. It would take several seconds for an app to open, the phone would freeze for one minute, volume controls on the lock screen wouldn't work, my Bluetooth range was literally less than 10cm, sometimes when I called the phone would mute my voice. I've tried resetting the phone twice. No luck. Then I've downgraded to iOS 10 and all problems went away; performance was similar to my previous phone. So, no battery problem, no buggy phone, just a very very buggy operating system (or an OS that purposefully slows down on older devices).

ant6n 9y ago

Knowing the issues with fixed in batteries these day, I purchased myself an LG G3, one of the few good smartphones with a replaceable battery. The idea is that once it goes bad, it'll be a simple switch. The problem nowadays is that it's almost impossible to get an original battery. On Amazon, everything is a fake. In stores, the battery does not exist anymore or is super expensive. It seems LG doesn't care, maybe they speculate people will just buy new phones. In a way, my approach to have replaceable batteries failed.

jjawssd 9y ago
ZeroLemon batteries have worked well for me for the last 3 years. I now use a gigantic 10,000 mAh battery with included custom back plate for my phone.

b212 9y ago

Does it affect only 6(S)? I'm thinking about getting SE as I have small hands and it looks like a perfect fit but I think it's kind of pointless to get a new iPhone with so serious, known and most likely impossible to fix, bug? SE is expensive to me as it is, I don't want to replace battery every year or so (I'm a heavy user).

dade_ 9y ago
I have an SE, nearly 2 years old and I didn’t notice any difference in performance with iOS 11, only improvements in the UI. Definately nothing as described by iPhone 6 owners which makes me think this is specific to certain devices.
lucaspiller 9y ago
Both my wife and I have three year old 5Ss, but our experience with iOS 11 has been completely different. For me it works just as well as 10, maybe even slightly better. For her it has turned her phone into a complete dog, even opening a contact in Messages takes seconds. Recently her battery has started to show signs that it is wearing out, such as jumping instantly from 5% to 30% when plugging it in to charge, so it looks like this behaviour is a software 'feature' on all iPhones.
graeme 9y ago
I have a five month old SE, works great. None of the issues which plague my friend's 6s. Can't comment on long run performance. I can say I've never heard it mentioned in these threads. I'd google SE battery throttling specifically though.

htsh 9y ago

One tangential weird experience: My iPhone 6s plus battery went obviously bad, as in reduced battery life and really big jumps down from 100 -> 70 and then from 40 -> 10 from minimal use. After months of dealing with the bad battery, hooking it up to my mac & running Coconut battery showed it was 46% good. So I took it to the store for an official replacement (I decided I would pay for it). The genius ran a diagnostic which showed the battery as fine (green, he called it) and almost immediately started to tell me why it may be something else in the phone and started pointing me towards buying another phone instead of getting the battery replaced. But for some reason their diag tool is worse than coconut battery or just wrong? If my battery were 60-70% good and they had lowered thresholds that's one thing, but my battery was long gone and they told me it's fine. And of course I insisted and the phone is fine now with a new battery. I know there's probably a decent explanation for it but it certainly felt like they really wanted me to buy a new phone, and that their diag tool perhaps isn't the most truthful right now when it comes to battery health.

epicide 9y ago
The 6S's had a bad batch or two. You might want to check if your serial number falls into that range: https://www.apple.com/support/iphone6s-unexpectedshutdown/ https://www.apple.com/support/iphone6s-unexpectedshutdown/
- htsh 9y ago
  Yup, I did and mine was fine. I mean I used the hell out of the phone since it came out and I knew the battery was bad just based on the cycle count and my heavy usage. I believe the tech checked as well right when I brought it in. What was weird was they told me the battery was fine and something else was wrong. And the phone has been fine since the replacement. And I think coconut is pretty reliable. We ran it on a couple of coworker phones before bringing my phone in, and mine was by far the lowest. Everyone was up in the 80s and mine was in the 40s. It ran multiple times with the same result. The apple tech told me green means it's in the 80s.
gargravarr 9y ago
Very nice tie-in to the planned-obsolescence theme others are throwing around - Apple would much rather push you towards buying a new phone (and because of their advertising, their target market would probably accept their reasoning) while a simpler option exists that won't make them nearly as much money.

waffl 9y ago

I replaced an aging battery on my 6S Plus a few months ago myself and installed iOS 11 at the same time (figured it was a good opportunity to do both together). Immediately I noticed my phone was basically unusable, incredibly slow, everything was crashing or locking up completely, I couldn’t believe it. I thought iOS 11 was the culprit, and even did a complete reinstall without restoring any backups to no avail. Finally, I noticed a slight dark spot on the LCD - the brand new battery I had bought was already bulging and in bad shape. I sprung for a better quality battery from ifixit and immediately the phone was running like brand new again. I thought the cheap battery had been supplying an unstable current, but perhaps there is indeed an issue with the software itself. One key thing I realized - ANY battery work done outside of Apple’s official repair means they will never work on your phone again. So if you care about having Apple do any kind of work on your phone (even if totally unrelated to battery), you will have to get it replaced by them.

Synaesthesia 9y ago
It’s very hard to get quality batteries outside of Apple which kind of sucks for iPhone repair. Yeah the 3rd party ones usually suck.
- waffl 9y ago
  Actually I feel almost any component in general sadly. I had to replace the front camera assembly as well and after trying almost four different parts from multiple vendors and none match the quality of the original. Another thing I learned is that Apple would replace the entire display and front assembly (front camera, earpiece, speaker, brightness sensor, proximity sensor) for only ~ $150. However, due to the third party battery they couldn’t work on it anymore.
  - Synaesthesia 9y ago
    Yeah the displays and touch panels are also sometimes inferior. That’s a real shame about your phone sorry.
- jakobegger 9y ago

ComputerGuru 9y ago

I bought an 8+ over an 8 hopping typing would be more accurate and faster on the larger screen (it’s not) thinking I would return it in the “no questions asked” period if not, but stayed for the incredible battery life. Before this, I had forgotten what it was like to be able to use your phone all day even after forgetting to plug it in the night before. Apple can make batteries that have awesome run times - they just choose not to so the phone can be x% slimmer. Bummer.

ComputerGuru 9y ago

So what’s the rationale for poor performance even when plugged in?

johnflan 9y ago

If that were true, wouldn't plugging in the phone alleviate the problem (while plugged in)

gargravarr 9y ago
See other comments. iOS appears to ignore the charger state and scale frequency based purely on the battery capacity.

overcast 9y ago

Damn my 6S is doing exactly this, loaded up CPU DasherX and it's showing it at 1200mhz instead of 1848mhz the 6S is supposed to be at. Just setup a service through Apple at the local BestBuy in an hour. Thanks!

fma 9y ago

I found a more permanent solution. Instead of replacing it with a new battery, I replaced it with a Samsung S8. There are some things I miss about the iPhone, and maybe I'll consider it again in the future..but after 3 iterations of iPhones I got off the hype train when "it just works" became "it just doesn't work". I also had issues with backups and lost data... My wife got the iPhone X (yes...I know, $1000) and she's encountered a few bugs/crashes. I make fun of her for it. I find the usability of my Samsung not as good as iPhone when iPhone was at the peak, but I'm ok with it beacuse I'm not buying a device that touts itself as 'it just works'...plus I got it for 1/3rd the price after massive discounts.

jonny_eh 9y ago
Are you saying that Samsung phone batteries don't go bad over time?
- bparsons 9y ago
  I think the issue here is CPU performance being tied to battery degradation as a method of planned obsolescence, rather than a complaint about iPhone battery life.
  - Retric 9y ago
    It's not really planned obsolescence, they made the trade off of CPU speed instead of battery life when the battery gets old. This is more reasonable than you might think as deep discharges use up batterie life faster. The other option is for the phone to not keep it's charge for nearly as long which would likely be more annoying. In either case it's a ~40$ repair to replace a phones battery and IMO a good idea at ~2-3 years old on all phones. Assuming you keep your phone for 4-5 years.
- fma 9y ago
  I'm saying I've invested a lot of money in a platform that touts itself as the best and user friendly. My recent personal experiences has shown that it is not. Hence, I refuse to pay the luxury tax on an item that does not provide me a good experience. Their tagline is "it just does". Sorry, no, it doesn't. I saved ~$500 when purchasing the flagship phone of another platform, so even if the experience is poor, I have an extra $500 in the bank. Also - the Samsung S8 gives you very fine control on throttling the CPU to save power.

opensports 9y ago

The title should be "If your iPhone or MacBook is slow, try replacing the battery." My MacBook Pro became so slow that I spent days trying to figure out why, only to discover it was my bad battery.

ak39 9y ago
Thanks for this. Would you know whether boot camp windows would also be affected by this?
- opensports 9y ago
  From what I've read I'm fairly certain it is not affected.

oger 9y ago

Had massive issues with my 6s during the last weeks. Upgrading to 11.2 significantly improved the laggy behaviour issue. However the Geekbench 4 results are interesting. Benchmark numbers for my iPhone 6S: Compute: 5551 / Multi-Core: 1732 / Single Core: 1045 versus "normal" 6S Benchmark numbers (taken from the app): Compute 10143 / Multi-Core: 3994 / Single Core: 2376. In summary my iPhone 6s is SIGNIFICANTLY (~2x) underperforming in this benchmark to where a "normal" 6s should be. How trustworthy are the benchmark figures in the app? Any other ideas? For the time being this seems to justify the suspicions.

SkyPuncher 9y ago

I wonder if any consumer protection laws will come into place. Particularly, those in the EU. While I see any argument for Apple doing this (helps keep the battery life high), this is not a disclosed feature. It's intentionally limiting the product's capabilities from what's marketed. People expect batteries to become worse with time - there is no getting around the fact that the chemical reaction becomes worse with use. A CPU, though, that should never see significant scaleback unless it's faulty.

jakobegger 9y ago
CPU running at max speed requires a lot of power. Degraded batteries have a higher internal resistance, which lowers the amount of power they can provide. So when the CPU draws a lot of power, the voltage on the battery drops. If the voltage drops to low, the battery protection circuit will shut it off. What people here don’t seem to understand is that capacity, battery health, and max power output are related. Old batteries just can’t provide the current that the phone needs. Battery replacements are cheap, and when your battery is degraded you should just swap it. Consumer protection laws won’t help you here. Apple is not pretending to sell a phone that doesn’t need service; on the contrary, they even strongly advertise their “protection plan” that would cover degraded batteries.
- GordonS 9y ago
  I think the biggest issue here is that your phone will do this silently. I think a better solution would be to notify the user and ask them if they want to go into the reduced power mode. I have an S7, and when the battery level gets really low it does exactly that (although it can actually take it even further if you want, switching off the radio, making the display monochrome etc).
  - jakobegger 9y ago
    Low power mode is something different, and iOS has that too. The problem here isn't that iOS isn't just trying to conserve power to last a bit longer. At some point the battery physically can't deliver the current required to run the CPU at max speed. At that point, the phone battery settings screen says something like "Battery Service Required". For some reason a lot of people get annoyed when their phone needs service. It's understandable, but I really don't see what Apple should do about it. When a car's battery needs to be replaced, people don't go complaining how their car is suffering from planned obsolescence, they just replace the battery.

alliao 9y ago

I used the AnTuTu benchmark app as I am cheap... and I found out my IO have scored lowly. Turns out having only a few hundred megabytes hinders the performance a great deal. After wiping 3GB of photos and videos the phone's gone back to it's snappy self. Though I'm still on iOS 10.3 or so...

punnerud 9y ago

It works! Replaced my battery now after this post and my score went from 810 to 1455, with a huge noticeable performance improvement and lower app loading time.