Dam, my iphone 12 pro max is 90% still. Maybe you should lay off finger flicking your phone.

300+ cycles I'm down to 91 or 92% battery life after 1 year. One aspect of limiting to 80% is it makes it more likely you'll hit 0-10% remaining more often or significantly more often, which also wears it down more quickly. So probably yeah, F the 80%, charge to 100% so you actually use the battery capacity you paid for instead of becoming a professional battery babysitter for all these devices, nobody pays you anything for this second job.

I upgrade my phones ... rarely. I still have an iPhone Xs Max that I purchased at release time so many many years later I'm happy that the original battery still gets me through the day (I'm not hooked to my phone screen all day).

So if after 12 months they saved 4 to 7% of the capacity, that's big 5y later.

I'm not sure why the word "barely" is invoked. ~20% additional degradation after 4 years of use is still significant, considering a *dying battery* is a common reason for changing phones.

So the question is, did Apple release this without real testing? Or did they test it, and decide that the small improvement was still worth shortening time between charges by 20%?

Incidentally, my Moto G goes for 3 days between charges, so I'd bet reducing the power consumption of the phone would go a lot farther towards increasing battery life, than reducing how much you can charge it.

Allowing a lithium ion battery to fully drain, and recharging, also puts tremendous stress on it. The key to maximizing battery life is to stay in the sweet spot, not fully draining, and not fully charging. These statistics are a lot better than some random anecdotes: [1]https://batteryuniversity.com/... [batteryuniversity.com]

[1] https://batteryuniversity.com/article/bu-808-how-to-prolong-lithium-based-batteries

94% is pretty good actually.

...that this setting halves decay.

How is that marginal?

All Apple did here was follow the generic advice from the supposed experts in battery chemistry who keep reiterating that your lithium ion type batteries will last longer if you don't charge them over 80% of their capacity (vs 90% or worse yet, 100%).

The other half of that is that it's not good for them to drop below a 40% charge either. In a perfect world, they like to optimally stay between a 40% to 60% charge.

Obviously, that's not incredibly useful in the real world, though -- so what we wind up with are batteries designed big enough so some degradation of the original capacity isn't considered an issue, plus a realization that except for the real extremes (discharged to nearly empty or charged all the way up and kept at a full charge for a length of time), the extra degradation is relatively minimal.

With your typical phone batteries, they're cheap enough so most people are fine with the idea they'll keep charging up well enough to give you hours of usage at a time for at least 2 or 3 years. Then you just replace them. When you've scaled this up so far, you're talking about multi-thousand dollar battery packs in electric cars? You're also looking at a situation where they get managed more actively by more complex monitoring/charging software, probably get actively climate-controlled, etc. So they're designed to have a much longer lifespan. But the same general thing applies. Charge them daily to 80% instead of 90% and you might get another year of decent life/use out of them? But you're talking about, say, 12 years instead of 11, or 11 instead of 10. Most vehicles owners don't care because they won't even keep their vehicle that long before trading it in, or they bought a used one where they don't have a way to even know the charging history the previous owner stuck with. So the typical advice is just to use it whichever way meets your needs best.

Note: I have and like my iPhone XS. But...

Sounds like reported battery life, at least on an iPhone, is "buggy".

I fully realize that the charged capacity is arbitrary - it's a cutoff, based on voltage calculations. They arbitrarily say "this is 100%" or "this is 90%". The solution to this isn't to "charge to 80%", it's to provide 20% more battery to the phones and charge to 100%, then consider everything -above- that "over charging" (and represent it as such - eg. 120%). Likewise, if the battery decayed to 99% or 97% or what have you (as a percentage of the threshold considered "fully charged"), it should simply report it as that percentage instead of lying and saying it's still getting the same percentage of charge.

This would be a much appreciated functionality for those of us who understand how batteries work. It's not like storage or a bucket, which you can "fill up" physically.

Personally, I purchased a 'battery case' for my phone and haven't been happier. I'm no longer worried about having to charge with an external battery pack on a long day of travel, and I no longer need to worry about the external battery pack. I don't really look at battery capacity anymore, it's usually somewhere between 80%-100% when I wake up and if I notice it's getting low, I'll turn the case on and top off to about 80%. I was able to take a 4-day backpacking trip without any concern for battery life this way (and had the phone off for most of the trip, but still).

> I have four percent more battery at 28 more cycles

You are fucking idiot if you qualify this is as barely. That was just one year . Do you you not think the effect will compound? After five years that's going to be a difference of at least 20%!

"but I just buy a new phone every year" said the idiot who "cannot afford" to drive an EV and pollutes endlessly while needlessly generating e-waste.

They COULD try something radical like making changing the battery easier than re-manufacturing the phone. The phone doesn't actually need to be thin enough to chop onions.

In my case, I'm on the fourth battery of my Samsung S4, and I began using a battery limiter app during the second one.

The last two batteries had (and still has so far) a longer lifetime than did the first one that actually became bloated after two to three years and the second one, I'd say about 75 to 100%.

That's why a swappable battery was a requirement for my new phone purchase and I had only a few models to choose from nowadays. Not going to renew a phone just for the battery just like buying a new car b

I charge my phone every day, and typically give it a boost midway through the day. When traveling I might charge it 2-3 times a day. In one year my phone probably gets charged 400 times, so in three years (about average for me) that's well over 1000 charge cycles. I'm not sure how long most people keep their phones for, but it's probably at least 18 months, unless you're prone to dropping yours.

I don't see the value in testing for less than 370 cycles. 300 cycles is probably the bare minimum the bat

Sure fire way to kill your battery is to keep cycling it. Instead of fully charging and discharging, top up when you get the chance.

Instead of charging to 80%, if I end the day >70%, I just don't charge. It's easy enough to charge in the middle of the day if you need to, but with the large battery on my google phone (the 6 pro), and the sipping that OLED screens do nowdays, if I don't use it too much, I finish above 70% on the first day... meaning I often have around 35% at bedtime on the 2nd day. Charge less often.

I use a similar setting on my Samsung - it only charges to 85%. By the end of the day it's only down around 50 to 60%, so I have exactly zero "usability" problems. It Sounds like this feature could make my battery last a couple more years, which is excellent. I'm not sure why they think this is a "marginal" result.

There have been several studies on this subject about half a decade ago. Which have been confirmed several times, most recent being just a few weeks ago for LiFePo chemistry batteries.

The general idea is that lithium batteries have two main failure modes. Loss of lithium inventory and dendrite growth, as well as several minor ones. The main problem for charge potential loss is loss of inventory. Basically when you charge the battery from the factory for the first time, it loses about 10% of its capacity immediately because some of the lithium in the electrolyte gets stuck to the negative pole permanently. Remaining capacity is then marked as nominal on the battery, and it moves in. But as battery is charged, more and more lithium is permanently stuck to that pole, causing continuous permanent loss of maximum capacity as you charge.

However by far the most damaging part of the cycle is 80% to 100%. That is when highest amount of lithium inventory loss occurs, and increase is exponential. So as long as you charge up to around 75-80%, your battery will be able to retain it's lithium inventory for much longer than if you charge all the way to full every time. This is why most modern phones and laptops have an optional charge limiter that will not charge lithium battery beyond 80%.

Overall, if you want to read some of the best papers on the subject, search for "Zsoldos" on google scholar.

iPhone's 80% Charge Cap Barely Boosts Battery Life in the first year

It's entirely possible that there will be a bigger benefit at the end of the second or third year. Maybe the year-over-year dropoff will be along the lines of 6%, 12%, 18% instead of 6%, 18%, 36%. If your battery is good enough that an 80% charge gets you through the day, it seems there's no reason not to.

... you're acting like it's already dying, even when it's still good?

299 times 80% charge means 299 times you told the battery it was "OK to be limited". I'd rather have the actual capacity available.

Personally, I don't kill a battery in a single day. Does charging my iPhone every two days make it last longer? Or should I go three days, when it will actually be low?

(no, I'm not a phone addict)

From the data provided, this is a useful feature. If you're planning on replacing your phone after two years, it's not worth it, but if you want to keep it 4+ years, it's clearly a good idea. If you're worried about running out of power, get a spare external battery (they're cheap).

Like everyone is saying, the headline is wrong, since the actual data in the article makes it obvious what most of us already knew: being gentle(r) with lithium ion batteries than what the manufacturer sets the max/min charge levels to can extend their usable life significantly.

Case in point: back in 2018 I bought three Moto G5 Plus android phones for myself and my family. Two of the three phones are still going strong, one is long dead. The difference? Two of us routinely charged to only 80%(ish) and wer

I've had the 80% limit set on my iPhone 15 Pro Max since the day I got it. It's currently showing 140 charge cycles (I dual-wield phones and sometimes switch to an Android device for a week or two for dev stuff), and a max battery capacity of 100%.

This is *much* better than I experienced with my iPhone 13 Pro a few years back. So I can't complain at all. And the 80% limit on my Pro Max leaves me with more than enough battery to get through the day, and then some.

I hate iPhones but, 4-7% is NOT insignificant. it is a reduction of close to 50% to normal, if anything it is bloody fantastic.

> "I'm not sure suffering through an 80 percent battery limit for 12 months was ultimately worth it."

I am not a phone addict. I might use 20% charge at most on a typical day on my Samsung A52. Then it is placed on a charger when I get home. It charges to 80% and stops. For all the people like me, and I suspect there are tons, there is no "suffering", it is just a pure bonus to limit the charging. On the very rare occasion I might want to ensure I have FULL capacity (I think I did it once, ever), I ju