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johannnn

macrumors 68020
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Nov 20, 2009
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Heat seems to degrade batteries.
I assume that the MagSafe heats up the phone quite a bit, since wireless tech is not very efficient and like 30% of the electricity becomes heat.
But I also assume that the phone gets warmer from wired 20W compared to wired 5W.
Has anyone seen a review or YouTube video on this?
Like is charging with a 20W wired charger every night bad for the battery.

edit: I’ve used my 11 on 5W Qi charger every night, and the battery health is only 93% now. I plan to buy the 12 but I’ll probably own it for 2-3 years. So I’d like to know the best way to keep the battery healthy.
 
I’ve been using a 40w charger for 4 years with serval iPhones.
7Plus, XSMax, 11ProMax. My current battery health is 93% on the 11 Pro Max that I’ve had since launch day 2019.
I’ll use it with a 12 PM if I decide to get one.

The XS Max had 99% battery health after a year. Using the same charger.
 
Yes, wether or not it’ll actually make a noticeable difference over time depends on a lot of factors. It’s always best to use the lowest wattage necessary.
 
If you're only going to keep the phone for three years, you can charge it as fast and long as you want. The battery will be able to take the abuse for that amount of time.

But if you were planning on trying to keep the phone for 5 years or longer, using the original battery, then yes, it would prolong its life to baby it will a little charger and not charge it fully very often
 
20W will wear out your battery faster . But if you have apple care or upgrade every year who cares
 
I always charge mine overnight so I’m using my old 5w brick, since it’ll strain the battery less and cause less heat. Since it’s on there 6-8 hours, I have zero need for fast charging.
For traveling and for my car charger, I’ll get a 18-20w charger since I’m more likely to need a faster charge in those situations.
Otherwise, if you’re worried about battery health, a lower wattage, wired charger will always be best. Anything wireless or “fast charging” will create substantially more heat, and thus, more damage.
 
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Heat seems to degrade batteries.
I assume that the MagSafe heats up the phone quite a bit, since wireless tech is not very efficient and like 30% of the electricity becomes heat.
But I also assume that the phone gets warmer from wired 20W compared to wired 5W.
Has anyone seen a review or YouTube video on this?
Like is charging with a 20W wired charger every night bad for the battery.

edit: I’ve used my 11 on 5W Qi charger every night, and the battery health is only 93% now. I plan to buy the 12 but I’ll probably own it for 2-3 years. So I’d like to know the best way to keep the battery healthy.
I’ve charged my 11 with a 7.5W Qi every night over a year and mine is still at 100%. My wife’s XR is at above 95% and it’s been charged daily for 2 years with 7.5W Qi charger as well. So it’s not the Qi charging, it’s the usage.
 
I have not seen any impact within a 2 year usage timeframe - and I've monitored battery capacity for years on these devices. Like others have said, unless you are planning on keeping your phone for 5 years, I'm not seeing any advantage to slow charging at 5w.

With the 11 Pro Max - the 5w brick that came with the old iPhones got REALLY hot - so much so I was not comfortable using it. For the 11 Pro or 12 Pro - maybe... but ... again... even if worst case scenario $79 over 3 years isn't enough for me to freak out about.

TLDR: I don't see an advantage within a ~3 year ownership.
 
I have not seen any impact within a 2 year usage timeframe - and I've monitored battery capacity for years on these devices. Like others have said, unless you are planning on keeping your phone for 5 years, I'm not seeing any advantage to slow charging at 5w.

With the 11 Pro Max - the 5w brick that came with the old iPhones got REALLY hot - so much so I was not comfortable using it. For the 11 Pro or 12 Pro - maybe... but ... again... even if worst case scenario $79 over 3 years isn't enough for me to freak out about.

TLDR: I don't see an advantage within a ~3 year ownership.
A lot of the battery babysitting on the forum comes from members who flip phones after a year, and want to keep the health in the 90s for better resale value (or so they hope). I don’t think the average person gets all consumed with the battery charging. Lol
 
A lot of the battery babysitting on the forum comes from members who flip phones after a year, and want to keep the health in the 90s for better resale value (or so they hope). I don’t think the average person gets all consumed with the battery charging. Lol
As one of those people (who upgrades every year but goes nuts on battery) - you speak the truth! :)
 
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A lot of the battery babysitting on the forum comes from members who flip phones after a year, and want to keep the health in the 90s for better resale value (or so they hope). I don’t think the average person gets all consumed with the battery charging. Lol
Personally, it's the opposite for me. Normalyl I flip phones every year so I don't care about the battery. It can't degrade noticeably in just a year. However, now I plan on keeping the 12 for 2-3 years. And I prefer the battery not being shi tty the 3rd year.
 
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I just don't see the point of fast charging at night. Even with the old slow charger it's going to be full in the morning anyway. So why risk even a small bit of faster degradation of the battery, if you don't have any benefit from it.
 
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I’ve been using a 40w charger for 4 years with serval iPhones.
7Plus, XSMax, 11ProMax. My current battery health is 93% on the 11 Pro Max that I’ve had since launch day 2019.
I’ll use it with a 12 PM if I decide to get one.

The XS Max had 99% battery health after a year. Using the same charger.
Mine is horrible. XS Max 87% fast charting in the last year. Went from 96% to 87%. Oh well. I’m definitely taking better care of my battery on my 12 Pro.
 
I've used Qi for my last two iphones and battery health has stayed in the >90% range. Pretty heavy use with near-flat by the end of everyday so I'm not too concerned. Also, if you upgrade yearly, no big deal..
 
i charge at night with a 5w charger and i have never seen the battery health drop under 100% , so i think it might be wise to use the slowest possible charger because of heat etc.
 
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I‘m pretty sure it is, especially if you’re only going to charge overnight, and don’t need to charge quickly.

Having said that: Do you actually care? At the end of it all, you may have a battery that lasts you 3 months longer on a 3 year old phone. If you want to replace it, then just pay Apple to replace the battery.
 
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Personally, it's the opposite for me. Normalyl I flip phones every year so I don't care about the battery. It can't degrade noticeably in just a year. However, now I plan on keeping the 12 for 2-3 years. And I prefer the battery not being shi tty the 3rd year.
It'll probably be noticeably worse by the 3rd year no matter what you do. Just plan to pay to have the battery replaced after 2 or so years.
 
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My iPhone 12 Pro charges from 20 percent to full in around 2 hours using the 5w charger overnight. I never need quick charging as I always charge overnight. though I have the 20w usb-c on the side in case.
 
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