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white4s

macrumors 68000
Original poster
Nov 15, 2011
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New Jersey
The battery health dropped from 98% to 95% since I switched to 18W in April. So,anyone need a 18W Anker usb-c charger or cord lol.
 
My XR Is also at 95%. I got it on Day 1. Mainly use regular charger but I do have an 18W charger. Guess I shouldn’t use it for the XR unless I have to. Thanks for the tip.
 
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I started wearing Nike socks six months ago and my battery capacity has now dropped 5%. Anyone want my socks? They're not too worn.

Kidding aside-
Theres ZERO evidence (only suspicion) that the 18W charger did ANYTHING detrimental to the battery.

  1. The battery health app indicator is widely known to not be accurate
  2. The battery health is going to diminish over time regardless of what you do with the iPhone or how it's charged
  3. The iPhone charger is built into the iPhone, not the wall power adapter. The iPhone (Apple) decides how much current can safely be pushed into the battery, not the 18 watt wall adapter.
If you plugged the iPhone into a 5000 watt (for a ludicrous example) power supply, the iPhone would only take what it needs. Just like if you plug a 12V lightbulb into a tiny 12 Volt battery or a giant truck battery (or 100 of them) the lightbulb only takes what it needs.
 
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Zero evidence from major source but plenty of Anecdotal to support this, my x drop from 90-84 in less than a month when I use iPad charger, since then I switch to the 5w and it’s been stable at 84 for a month now. There are plenty advices here from folks claiming the higher wattage won’t deteriorate the battery, because of them I had to get my battery swapped by Apple twice last year costing me 100 bucks
 
Makes sense. Even though the iPhone can gladly accept higher wattage, a side effect is increased temperature in and around the battery and heat is a common denominator in any battery’s degradation, regardless of the battery’s chemistry.
 
Zero evidence from major source but plenty of Anecdotal to support this, my x drop from 90-84 in less than a month when I use iPad charger, since then I switch to the 5w and it’s been stable at 84 for a month now. There are plenty advices here from folks claiming the higher wattage won’t deteriorate the battery, because of them I had to get my battery swapped by Apple twice last year costing me 100 bucks

The 18W charger has a tendency to raise the temperatures which is the cause for deterioration and not using the charger itself.
If the iPhone is in a case that doesn’t allow proper heat dissipation then yes, your battery’s gonna lose its capacity faster. Other than that you’re not gonna see any noticeable loss is capacity from just using a fast charger.
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Fast charging reduces long term battery life. This is a well known fact since years now.

Most people tend to not account for the extra heat produced during charging at higher wattage which is the primary cause of battery deterioration. You can charge using the less powerful 5W charger and still lose more capacity if the surrounding temperatures are high enough.
 
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The battery health dropped from 98% to 95% since I switched to 18W in April. So,anyone need a 18W Anker usb-c charger or cord lol.

It dropped 2% in the 6 months since you got it in October 2018, then 3% in the 7 and a bit months since you switched your charger in April. Bear in mind the figures are rounded, it could easily have been 2.4% and 2.6% lost in those timescales respectively.

Go get a calculator, see that it's a whole lot of nothing, and keep on enjoying your phone.
 
The battery health dropped from 98% to 95% since I switched to 18W in April. So,anyone need a 18W Anker usb-c charger or cord lol.
I'll take your cord.

Maybe your battery life just declined from using your phone and charging it since April?
 
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Zero evidence from major source but plenty of Anecdotal to support this, my x drop from 90-84 in less than a month when I use iPad charger, since then I switch to the 5w and it’s been stable at 84 for a month now. There are plenty advices here from folks claiming the higher wattage won’t deteriorate the battery, because of them I had to get my battery swapped by Apple twice last year costing me 100 bucks
Similarly there are anecdotal discussions about people seeing noticeable battery health/capacity drops without the use of much more powerful power adapters.
 
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Fast charging reduces long term battery life. This is a well known fact since years now.
Wrong. Temperature reduced long term battery life (among other things like charging cycles).
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The battery health dropped from 98% to 95% since I switched to 18W in April. So,anyone need a 18W Anker usb-c charger or cord lol.
The only point I can see here is it was April and today is December.
That’s why the battery health dropped. Normal use (and charging).
 
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To back up akash.nu's statement, during the summer I can't use my 12 watt iPad charger to charge any of my iPhones. They get way too hot during charging with that charger (5.5 watts going in typical) versus using the little 5 watt charger (2.5-3 watts going in typical). But that's because the ambient temperature is usually over 105° mid day. But during the other seasons, temperature isn't an issue.
 
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To back up akash.nu's statement, during the summer I can't use my 12 watt iPad charger to charge any of my iPhones. They get way too hot during charging with that charger (5.5 watts going in typical) versus using the little 5 watt charger (2.5-3 watts going in typical). But that's because the ambient temperature is usually over 105° mid day. But during the other seasons, temperature isn't an issue.

Exactly why I hibernate my fast chargers through summertime.
 
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What? That’s nothing. 🤣

If anything I’d say that was fair if you were using a normal charger. Even decent.

Before I upgraded to my Pro Max, my iPhone 7 suffered way worse then that, it was in upper 80’s after less then a year with the standard brick and cable.

Lastly that number is a rough estimate, I find it can even bounce around. My iPhone 7 once went from 92% back up to 95% where it stayed for over a month.
 
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And just leaving a video link here for a little more explanation for those looking for more information on this.


 
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Unless you're charging your phone in direct sunlight, the phone will ask for the current it deems safe from the power brick. That and, the phone will shut itself off when it gets too hot.

I've been using 50w and 60w 2.4amp Anker chargers for the last 5+ years. My phones (6+, 6s+, 8+, Xs Max, 11 Pro Max) rarely lose more than a few % from their design capacity over the course of 2 years (when I get rid of them).

Now, most of my phone's battery percentages stays between 100-90% so it is rare for me to get into full speed charging (anything past 80% slows to a trickle charge) unless I go out for the day on vacation.

Use coconutBattery to observe your battery consistently over the course of your phone's life.

Yes, heat is bad. I usually don't use my phone when it is charging - I know playing some intensive games while charging sub 80% can get the phone pretty hot. I wouldn't do that for the longevity of my battery.

That said, I've used >=2.4amp chargers since my 6+ and have not seen a detriment from using them.

If I was going to keep my phone 5+ years, I'd use the 5w 1amp brick only and try the 40-80% optimal charge level. But within 2 years, I have not seen much of an effect of doing 90-100% and fast speed charging.


Heat kills. I can't count how many times I see people leaving their phones in the sun, in hot cars, getting them to the point where they'd boil an egg...

https://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
 
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Zero evidence from major source but plenty of Anecdotal to support this, my x drop from 90-84 in less than a month when I use iPad charger, since then I switch to the 5w and it’s been stable at 84 for a month now. There are plenty advices here from folks claiming the higher wattage won’t deteriorate the battery, because of them I had to get my battery swapped by Apple twice last year costing me 100 bucks

I don’t know what is causing that but it is not the power brick
 
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The Apple Genius claims that my iPhone X's battery issue (87%, but says it needs SERVICE) is use of non-apple approved charger. I generally use a 7.5w compatible Samsung wireless charger at night, and used to use a multi-port USB charger there. I don't know how much of its issue is this, or the fact that the phone is used too much anyway (multiple short periods during the day at work, etc).

The iPhone 6 I used for 2 years also needed a new battery at 2 years (and is still fine on the replacement battery 3 years later with current owner). So I tend to blame my usage pattern.

And I plan to replace around Christmas. Out of stock Thanksgiving weekend at Apple store where I wanted to replace battery.
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Forgot to mention that my sister's 2 year old SE needs a new battery too. Demonstrated unexpected shutdown. She has almost exclusively used a 5w iPhone charger that came with iPhone.
 
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