
If your iPhone is slow, try replacing the battery - EduardoBautista
https://www.reddit.com/r/iphone/comments/7inu45/psa_iphone_slow_try_replacing_your_battery/
======
lwansbrough
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.

~~~
jpalomaki
In the Reddit comments somebody claims this is actually a software fix for the
6s battery problem that was causing shutdowns when battery level fell below
certain level.

There's a free battery replacement program for the models affected [1].

My phone was one of the affected, but never got around to take it to repair
shop because I thought the few random shutdowns were the only problem.

[1]
[https://www.apple.com/support/iphone6s-unexpectedshutdown/](https://www.apple.com/support/iphone6s-unexpectedshutdown/)

~~~
ksec
The problem is, there are other people in the thread claiming their iPhone 6
or iPhone 7 were also performing poorly according to Geekbench. Surely iPhone
7 isn't / shouldn't be affected by this batch?

If this is true that apple throttle its performance due to battery Cycle, I
will pissed too. Apple should have noted to me within iPhone that i should get
a Battery replacement in the Apple Store, or I will be bringing my own Battery
Pack when I am out.

~~~
ksec
After 24 hours and putting lots of thoughts into it, I could not even argue
for Apple.

Out of the bulk load of Energy Usage, CPU is not even the primary area where
energy are used.

40%+ is the Display 20%+ are the Network Connection, WiFi or LTE. 10%+ are
RAM, NAND, etc.

I am guessing around 20% is the CPU and GPU. So they lower this and try to
save 10% more battery in response to lower battery cycle?

And they have an Financial interest to slow your phone. This makes me sick.

And I consider myself an Apple Fan.

------
shasheene
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)

~~~
m_ke
I used to think that was a joke, but since updating to ios 11 my 6s+ has been
completely unusable. A bunch of the apps are now unresponsive for 5-10 seconds
after they launch, the input lags and the standard ios animations are dropping
a ton of frames. Battery is also sometimes draining 20-40% in a span of 15
minutes.

~~~
jonplackett
I have a 6s plus and had the exact same thing. Phone was totally unusable. But
I did a full backup and reinstall and it’s gone back to normal speed. Feels
like a new phone. Give it a try.

~~~
grendelt
6s plus here too. So just backup, total reset, then restore? No battery
replacement?

If so, I’m in for a try.

~~~
sliverstorm
A common approach on Android. Nobody really seems to know exactly why, but
evidently crap accumulates, either from old apps or from sloppy in-place OS
upgrades. A full reset clears all the crap, and you start anew.

I prefer to skip even the backup step, instead relying on cloud sync for
contacts etc, and manually dumping a couple apps.

------
woopsie111
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
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
One word: Shareholders.

------
fma
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
Are you saying that Samsung phone batteries don't go bad over time?

~~~
bparsons
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
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.

------
qd6pwu4
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.

~~~
pixelcloud
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.

~~~
foldr
LiPo batteries generally supply from 4.2V to 3.7V from a fully charged state
to a fully discharged state. Modern CPUs run at under 2V. If the battery was
directly connected to the CPU, the CPU would fry.

[https://en.m.wikipedia.org/wiki/Buck_converter](https://en.m.wikipedia.org/wiki/Buck_converter)

That being said, it's conceiveable that a worn out battery might not be able
to supply enough power to run the CPU at higher clock speeds.

~~~
gargravarr
Not to nit-pick, but 3.7v is the nominal cell voltage. They can supply power
down to 3.3v safely. Fully discharged is around 3.0v.

~~~
foldr
Ah yes, thanks for the correction.

------
htsh
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
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
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.

------
waffl
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
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
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
Yeah the displays and touch panels are also sometimes inferior. That’s a real
shame about your phone sorry.

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

~~~
dannyw
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
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
Apple doesn’t officially document that, but see various support discussions:

[https://discussions.apple.com/thread/4468165](https://discussions.apple.com/thread/4468165)

------
givinguflac
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.

~~~
SkyPuncher
Reddit OP made an edit indicating he tested the old battery again and found
the same results.

------
terminalcommand
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
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.

~~~
gaadd33
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?

~~~
drawkbox
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-
drai...](http://bgr.com/2016/11/30/iphone-7-vs-iphone-6s-battery-drain/)

[2] [https://www.macrumors.com/2017/10/01/apple-looking-into-
ipho...](https://www.macrumors.com/2017/10/01/apple-looking-into-
iphone-8-battery-failures/)

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

~~~
ericabiz
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
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.

~~~
starky
>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
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
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
Again, I'm not versed on the chemistry behind this, but friends who got new
phones around the same time and plug them in to charge every chance they get
have had their batteries fail earlier than me. I guess my data is anecdotal,
but doing full cycles has allowed me to get 40+ hour standby with 10+ hour
screen over the last one and half years. Where my friends cant even get more
than 10 hour standby.

~~~
owenversteeg
As someone who builds battery systems (yes, I'm "that battery guy" that shows
up in HN battery threads) wtallis is correct: full discharges harm modern
batteries, although every battery protection circuit has a cut-off voltage set
to prevent discharging them too far (at which point your phone will turn off.)

The practical applications of those two facts, however, are much more nuanced.
Ultimately, the biggest killer of batteries is heat. Charging your phone and
using it battery-intensively (max brightness/lots of processing stuff) are the
biggest heat-causing things that come to mind. Another thing that can happen
is heat buildup: you might not be using it very intensively, but if you use it
for hours on end the heat can eventually build up and the phone will get
hotter over time.

It's entirely possible that your method of using your phone actually does
cause less stress on the battery. However, this is 100% dependent on what you
and your friends do with your phones, before and while they charge, as well as
the kind of phone, its charging circuitry and a million other factors.

At the end of the day, all I can say is "batteries are basically magic, use
less power, and don't let your phone get too hot." The only universal
recommendation that will guarantee better battery lifetime - with every
battery chemistry - is to draw less current from the battery (on a phone: turn
down your brightness, turn off things you're not using, etc etc.)

------
opensports
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
Thanks for this.

Would you know whether boot camp windows would also be affected by this?

~~~
opensports
From what I've read I'm fairly certain it is not affected.

------
ant6n
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
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.

------
SkyPuncher
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
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
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
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.

~~~
GordonS
> they just replace the battery

Is it even possible to replace an iPhone's battery though?

I would guess if Apple offered battery replacement as a service, at a
reasonable price (not very Apple-like, I know!), people would use it.

~~~
jakobegger
Apple offers iPhone battery replacement for around $80, third party repair
shops will do it for $30, and if you do it yourself you can order a kit
(battery+required tools) on Ali Express for under $10

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

------
b212
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).

~~~
lucaspiller
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.

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

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

------
revelation
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
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.

------
oger
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.

------
milankragujevic
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...

------
overcast
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!

------
askvictor
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.

------
alliao
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...

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

------
punnerud
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.

------
napsterbr
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).

------
joelthelion
I wonder if Android has something similar?

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

