In-Depth iPhone Battery Experiment Pits Slow Charging Against Fast Charging

[MacRumors]

HTX Studio this week shared the results from a six-month battery test that compared how fast charging and slow charging can affect battery life over time.

Using six iPhone 12 models, the channel set up a system to drain the batteries from five percent and charge them to 100 percent over and over again. Three were fast charged, and three were slow charged.

Another set of iPhones underwent the same test, but with charging initiated at 30 percent and stopped at 80 percent, so the iPhones were always in that range.

Prior to the experiment, the capacity for each phone was tested, and after 500 cycles, the capacity was tested again. The results suggest there is minimal additional battery drain from fast charging, but keeping an iPhone between 30 and 80 percent charge could be minimally beneficial.

HTX Studio concluded that the best way to charge an iPhone is "however you like," without overthinking it and trading mental energy for a tiny bit of battery life. The same video also includes Android tests, and is well worth watching in full for those curious about the effects of fast charging.

Article Link: In-Depth iPhone Battery Experiment Pits Slow Charging Against Fast Charging

 

[cateye]

Telling people to not “overthink” battery life and charging, and backing it up with data, is going to absolutely rock the world of a great number of posters in the iPhone forum. Thoughts and prayers.

 

[dustin_]

wow, just like every other battery test. replace your battery if/when it falls under 80%. otherwise, use your phone as you see fit, folks.

 

[max2]

A lot at least half already knew this. Still a good test.

 

[LowKeyed]

I've always been a fan of the idea that your phone (or any device) should work for you, not the other way around. If it is easy for you to manage your battery, great. But don't work so hard for it. You are unlikely to significantly change the usable life of a modern battery and compared to the effort some people put into it, it is not a smart trade.

I've always felt the same way about OSes. You shouldn't have to work so hard to keep your OS organized, secure, updated, etc., again, you got a computer/device to improve your life, not complicate it.

 

[0423MAC]

It just doesn’t make sense to limit yourself to stay within a range now to possibly save a few percentage points later.

 

[ValerieDurden]

It just doesn’t make sense to limit yourself to stay within a range now to possibly save a few percentages later.

The 80% crowd isn’t going to like that lol.

 

[el-John-o]

This comes up a lot and every test is more or less the same.

Marginal benefits if you make some pretty significant compromises every day for forever.

If you only charge to 80%, your capacity will hold slightly longer. Capacity that... you're not using.

If you fast charge every day for years all the way to 100%; you'll still have 80% capacity at the end of several years. Capacity that you would've been artificially limiting yourself to the entire time.

Feels very "cover the couch in plastic" to me. Sure I guess it improves it somewhat; but is it worth not getting to actually use the "thing"?

And ultimately, battery replacements from Apple are both reasonably priced and available for a very long time, with third party options virtually indefinitely.

I keep my phones for a really long time so, in theory, I'm the one this information most benefits. The only thing I actually do is make sure to use a slow charger on my nightstand. When I plug it in at night, it's going to be plugged in for the next several hours so there's no benefit to fast charging. Beyond that, it gets hit with a fast charger if I ever need to charge in the middle of the day. Always to 100%. And after 3-4 years the battery capacity starts to get noticeably poorer. A hundred bucks (give or take) at the Apple Store (free with AppleCare+) and I walk away with a brand new battery. And most people will have replaced their phone long before then.

 

[el-John-o]

It just doesn’t make sense to limit yourself to stay within a range now to possibly save a few percentage points later.

For sure.

If you limit yourself to 80% then after 4 or 5 years you can avoid a battery that only... has 80% of it's capacity left?

What exactly have you accomplished?

Let's imagine a phone owned for 6 years. One person limits it to 80% and has 80% capacity for 6 years. The other person doesn't limit it at all and ends up with 80% capacity and maybe a smidge under for a year or two?

...I really don't get it. Like genuinely. How is the first scenario not the obviously, clearly, no brainer, no question worse scenario? How is a capacity life of 100, 96, 92, 88, 82, 80 better than a capacity lifetime by year of 80, 80, 80, 80, 80, 80?

 

[0423MAC]

The 80% crowd isn’t going to like that lol.

I mean think about how silly it is.

you effectively cut your battery life in half on day one to stay above the 80% threshold after your phone is already a few years old and will likely want to replace anyway.

 

[Tonewheel]

So, is that kid in Junior High, or...?

 

[Ender17]

would like to see a test with Qi charging as a variable since anecdotally I seem to have above average battery health with my phones after 1 year of use and never use it but still pretty cool test

 

[kalafalas]

This comes up a lot and every test is more or less the same.

Marginal benefits if you make some pretty significant compromises every day for forever.

If you only charge to 80%, your capacity will hold slightly longer. Capacity that... you're not using.

If you fast charge every day for years all the way to 100%; you'll still have 80% capacity at the end of several years. Capacity that you would've been artificially limiting yourself to the entire time.

Feels very "cover the couch in plastic" to me. Sure I guess it improves it somewhat; but is it worth not getting to actually use the "thing"?

And ultimately, battery replacements from Apple are both reasonably priced and available for a very long time, with third party options virtually indefinitely.

I keep my phones for a really long time so, in theory, I'm the one this information most benefits. The only thing I actually do is make sure to use a slow charger on my nightstand. When I plug it in at night, it's going to be plugged in for the next several hours so there's no benefit to fast charging. Beyond that, it gets hit with a fast charger if I ever need to charge in the middle of the day. Always to 100%. And after 3-4 years the battery capacity starts to get noticeably poorer. A hundred bucks (give or take) at the Apple Store (free with AppleCare+) and I walk away with a brand new battery. And most people will have replaced their phone long before then.

The couch analogy is absolutely perfect, I’m going to start using that.

It’s not even really useful to slow charge overnight. The fast charger stops charging a lot sooner, so you get the same amount of heat just spread over more time. So it really truly doesn’t matter!

 

[Aichon]

Data point for anyone curious: my 4+ year old iPhone 13 Mini—without the 80% limit (it's old enough to not support it) and charged nearly exclusively via MagSafe every night—is still at 83% of its maximum capacity. So, yeah, I tend to be in the "don't overthink it" crowd.

 

[lerschiboi]

I guess I’m one of the few people who only has 2-3 h of screen time per day, which still feels too much.

So I’m fine with limiting my charging to 90% and and potentially having a slightly better battery in a couple of years when I sell the phone.

But I see how this behavior doesn’t make much sense for must people who use their phone more…

 

[jwdsail]

HTX Studio this week shared the results from a six-month battery test that compared how fast charging and slow charging can affect battery life over time.

Using six iPhone 12 models, the channel set up a system to drain the batteries from five percent and charge them to 100 percent over and over again. Three were fast charged, and three were slow charged.

Another set of iPhones underwent the same test, but with charging initiated at 30 percent and stopped at 80 percent, so the iPhones were always in that range.

Prior to the experiment, the capacity for each phone was tested, and after 500 cycles, the capacity was tested again. The results suggest there is minimal additional battery drain from fast charging, but keeping an iPhone between 30 and 80 percent charge could be minimally beneficial.

HTX Studio concluded that the best way to charge an iPhone is "however you like," without overthinking it and trading mental energy for a tiny bit of battery life. The same video also includes Android tests, and is well worth watching in full for those curious about the effects of fast charging.

Article Link: In-Depth iPhone Battery Experiment Pits Slow Charging Against Fast Charging

Good to see some actual testing of some of these charing methods and how they may (or may not) affect battery life.

I'd love to see a similar test pitting the 80%/90% charge and charging to 100%.. but, leaving the phone in low power mode (I can get still two days of battery life on my year old 16 Pro doing that) (half the charge cycles, all the power)

 

[Ct applefan]

It just doesn’t make sense to limit yourself to stay within a range now to possibly save a few percentage points later.

Not worth the effort. I just MagSafe my phone every night to 100%. iPhone 15PM. Battery life is a 88%. I’ll replace the battery when it hits 80%

 

[CharlesShaw]

If you use your iPad or MacBook on a desk eight hours a day, is it better to leave it plugged in all day at 100%, limit it to 80%, or unplug it and let it drain and recharge it every day?

 

[VisionProRocks]

Wish I could limit my macbook to 80% as it's docked 24/7. I don't limit my devices that are mobile for the already discussed reasons.

 

[klasma]

keeping an iPhone between 30 and 80 percent charge could be minimally beneficial.

More than minimally, I would say. The 5-100% iPhone lost 12% capacity, while the 30-80% iPhone lost only 8% capacity. This means the 5-100% iPhone lost battery capacity 50% faster,

 

[sleeptodream]

For sure.

If you limit yourself to 80% then after 4 or 5 years you can avoid a battery that only... has 80% of it's capacity left?

What exactly have you accomplished?

Let's imagine a phone owned for 6 years. One person limits it to 80% and has 80% capacity for 6 years. The other person doesn't limit it at all and ends up with 80% capacity and maybe a smidge under for a year or two?

...I really don't get it. Like genuinely. How is the first scenario not the obviously, clearly, no brainer, no question worse scenario? How is a capacity life of 100, 96, 92, 88, 82, 80 better than a capacity lifetime by year of 80, 80, 80, 80, 80, 80?

Doesn’t peak voltage also go down as a battery degrades? Isn’t that why Apple reduces performance when the battery falls below a certain percent health?

That’s what I’m concerned with myself, not the battery life hit, I get plenty of battery life either way

 

[Artemiz]

If you use your iPad or MacBook on a desk eight hours a day, is it better to leave it plugged in all day at 100%, limit it to 80%, or unplug it and let it drain and recharge it every day?

Charging to 100% isn’t the issue. It’s how long the device stays at 100% that affects the battery health.

Best practice is to keep the MacBook plugged in but limit to 70 or 80% while running it on battery every few days.

 

[max2]

Charging to 100% isn’t the issue. It’s how long the device stays at 100% that affects the battery health.

Best practice is to keep the MacBook plugged in but limit to 70 or 80% while running it on battery every few days.

Good point and your right.

 

[Artemiz]

Wish I could limit my macbook to 80% as it's docked 24/7. I don't limit my devices that are mobile for the already discussed reasons.

You can limit MacBook using AlDente.

 

[840quadra]

Nice, but I am going to follow industry / manufacturer suggestions. I still am rocking a 13 pro with over 80% battery as my work phone, and have turned in my last devices on personal side with 99 - 100% battery health since the 14 pro on.