They changed to lower quality batteries since iPhone 14 this feature is just to hide what they did. Trying to convince users to use 80% creating the illusion of a better battery.
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iOS 18 Actively Recommends Charging Limit Based on iPhone 15 Usage
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How much time does this take away from my being able to use my phone? We are talking about 20% less of a charge, right? Doesn't that subtract from the time I can actually use my phone?
I wonder what the long term effect on the battery health is, realistically from 80%-85%. I've seen a bunch of articles that say while charging to 80% is best for battery health, the real negative effect isn't seen until the battery is charged over 90% of its capacity.
I currently have mine set to charge to 80% but was probably going to move it up to 85% like you. Although my normal day of use I barely use 45% of the battery.
I have an iPhone 14 Pro and my battery is already shot. I’m down to 85% maximum capacity.
I am a light user and my XS is still at 87% on its original battery. Since I only tend to charge every other day or so it never learns enough to limit to 80% and just does 100% each charge.
Out of interest, how low in %battery does it tend to get before Peak Performance is limited anyway?
Out of interest, how low in %battery does it tend to get before Peak Performance is limited anyway?
Furthermore we have to keep in mind that these %-stats in the system aren’t matching the real battery capacity. 0% is thankfully not a real zero, otherwise it would hurt the battery while when the stats showing 100% the battery isn’t totally full, same here to prevent battery health.
for crying out lout, let all phones use this feature and spare the environment tons of lithium waste. stop the feature rationing, particularly with a minuscule one like this that all supported models of iphone are capable of.
if you are a heavy user and don't want the feature, leave it off, but i would guess most users don't fall into that camp, or have plenty of opportunites to top off at work, car, whatever.
i would rather have my battery last longer when *i* actually need it (i.e maintain 100% peak performance so when I do need to take that to 100% charge it is actually capable of a real 100% charge), not some ridiculous algorithm.
if you are a heavy user and don't want the feature, leave it off, but i would guess most users don't fall into that camp, or have plenty of opportunites to top off at work, car, whatever.
i would rather have my battery last longer when *i* actually need it (i.e maintain 100% peak performance so when I do need to take that to 100% charge it is actually capable of a real 100% charge), not some ridiculous algorithm.
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There should just be a Shortcut action for this and you could have all the flexibility you want.
Even on Apple's support document, it doesn't say what the benefit is. https://support.apple.com/en-us/108055
I understand why it makes sense to not fast charge the top end of the battery, but what are we saving by never charging above 80%?
I understand why it makes sense to not fast charge the top end of the battery, but what are we saving by never charging above 80%?
You're reducing the accumulation/creation of dendrites.
Dendrites are crystal-like formations in the cell that grow through the electrolyte, little by little, with each charge and discharge cycle. They cause short-circuit in a cell when they grow all the way through. This is the main way a li-ion cell dies.
Dendrites are formed primarily during deep charging and deep discharging. E.g., when you discharge the battery down to 0%, and when you charge the battery up to 100%. If you stay within the 20%-80% charge range all the time, a modern lithium ion cell can last probably 10x as many cycles compared to a battery that is cycled between 0% and 100%. But staying in that narrow range sacrifices 40% of the battery capacity, so it's pretty undesirable. Indeed, everything about battery design is balancing competing interests and picking 2 of 3 options.
Most battery controllers don't let you go to 0% anyway. When your phone is reporting 0%, it likely really means the battery has 1-3% left but for self-preservation it's not going to let the device turn on in that state. And most folks don't discharge their phone all the way daily anyway - it's a rare occurrence to be plugging in a totally dead phone. But most battery controllers let the battery charge to 100%. So dendrites slowly form.
By limiting the charging to 80%, you're greatly reducing/slowing the formation of dendrites.
But 80% is a bit aggressive in my opinion. Dendrite formation becomes a real problem at the extremes. 90-95% charge limit would be fine I think.
taking lithium ion past
in a nutshell, the higher you take a lithium ion battery voltage the quicker you begin to break down the materials that makeup the structure of the cell. you can find more detailed info on this online, but you can think of it like blowing a balloon to it's max and deflating over and over again weakening the structure of balloon.
Interesting - I've had this feature enabled and set to the 80% since I got my iPhone 15 Pro after the fiasco that was the 14 Pro battery (I was at 87% health after less than a year). So far my 15 Pro I've had since mid-December is still 100% health. I don't see any type of recommendation though. I wonder if it only makes recommendations if you don't have the feature turned on? I'd be curious to know if my usage patterns would merit maybe doing 85% or 90%, but it doesn't seem to have that type of awareness, at least not yet.
you cannot, but that would be really,really great if you could. that would open up the possibility of a lot of customization.
This is a great educational service that will help the future owners of electric cars. It is good to learn good habits with a phone where the battery is cheap compared to learning this on your car where the battery might cost $10K.
So many people charge to 100% because "I might need it" and then complain that the battery life is poor. It is best to learn the 80% rules on a phone.
Electric cars will be the only car you can buy in 11 years in many places and people need to learn how batteries work and to better manage charge. IKt is good that Apple eill educate consumers now so they will be smarter later.
Many places in the world have requirements in place for zero tailpipe emissions starting in the 2030s. This is not just a "California thing" but worldwide. China is the largest market for new cars and is leading this, Europe too. People will be better off after they learn that you do not need a 100% full battery. You are best off if the battery has only enough charge to last until you will be able to charge it again. Tesla has the best system for this, their computer knows where you are going (because you told it) and charges only enough to get the trip done, no more. If you let this system manage charging, your battery might last for decades. But if you are stupid and use the supercharger to get to 100% at every charging opportunity you might kill the battery in only a few years. Same with an iPhone. Let's hope makes this very clear so as to change user behavior.
Apple will be doing a good service if they educate people.
Yes, but you are rich and can afford to replace the battery or the entire phone. But what if living in Oklahoma where a "good job" pays $18 per hour or what if you were in China where the pay is even lower?
Most people in the world are not rich and postponing a repair that would cost them 10 or 40 hours of their labor is a very valuable thing.
For you and me, a few hundred dollars is not a big deal. But for 80% of the world, it is s big deal.
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I feel your pain, but as we, regular iPhone 15 users, have recently learnt, our phones do not have a minimal amount of RAM (8 GB) to handle the AI stuff. A pity…
A lot of us don’t use more than 80% on a typical day. No point in abusing the battery for capacity you won’t use. When I expect to do more, I can switch it to 100%.