iPhone 12 Pro Does it really shorten a battery’s life leaving it plugged in overnight?

[Ledsteplin]

I'm an electrical engineer with some experience with lithium, nickel cadmium, nickel metal hydride cells.

With Li-Ion (or really Li-Polymer in your iPhone) with the latest versions of iOS it's totally safe. They learn your charging pattern (when you sleep) and charge up to 80% quickly and hold it there until just before you wake where it will charge the last 20%. That way the phone minimized the length of time the battery will spend above 80% which over years and years of use can really add up, a small change that will probably provide a considerable boost to cell life. Basically 5 or so hours each day less the cell spends at 100% x perhaps over 1000 days is a lot of wear saved.

Most of the damage done to cells is 80%. The closer you are to 0% or 100% the more you are causing chemical damage (like dendrite formation) to the cell. Of course number of cycles is a thing too. Ideally you'd keep a battery permanently charged at 50% at perfect operating temperature but that isn't realistic.

TLR if you are on the latest iOS just put it on charge when you go to sleep, the phone will take care of the rest and avoid running it down below 10% as much as possible.

I don't use battery optimization on my 12 Pro Max. I charge to 100% each charging with a fast charger. I've had it for 8 months, and the battery is still at 100% battery health. And I'm a heavy user.

 

[Isamilis]

A guy at a phone repair shop told me this. I have conversely read that this is a myth. What is the deal, and why?

It does. Not a myth. Manage your battery at 45-75%, you will be fine.

 

[jay968]

This is a common question. I've responded to several threads in the past, pointing out the following;

Most people who use cell phones and are as obsessed with them as people who frequent forums such as these will end up upgrading their phones far sooner than the battery will last, no matter how they charge them. I owned a 5c for 7 years and the only reason I got rid of it was because many of my apps would no longer update in it. I put that phone on a charger every single night for for the entire night since day one and never had any battery problems. I am still using (typing on it right now) a 2012 Macbook pro that I have used every day since the day I purchased it, the battery is almost always on charge, and the battery threshold (just checked it) is at 50%...pretty good for 9 years of heavy use and charging!

Don't worry about charging a battery overnight. Yes it is better to manage its charging, but it is honestly not going to make a fig of difference for hardly anybody.

 

[neutrino23]

Sometimes you see stories about the benefit or harm of different ways of charging batteries. Mostly that has to do with plain batteries connected to a steady source of power. This is not the case with the battery in an iPhone, iPad or MB. Apple knows really a lot about batteries and they put this to use in how the battery is charged and discharged. It is totally safe to leave the iPhone on the charger all night. The computer in the iPhone is changing the power applied to the battery depending on the state of charge to safely bring it to full charge.

 

[jr866gooner]

I’ve a shortcut that sends me a message when charging and hitting 82%

I might sometimes let it get to 88% or 90% but rarely more.

Only once in the last 6 months or so have I fallen asleep with the phone charging overnight. I typically charge the next morning where I can stop it before it gets too high.

 

[827538]

I don't use battery optimization on my 12 Pro Max. I charge to 100% each charging with a fast charger. I've had it for 8 months, and the battery is still at 100% battery health. And I'm a heavy user.

OK, but that doesn't change my advice or show anything is incorrect. Just that you haven't had your phone's battery health drop yet.

 

[1rottenapple]

May it shortens it to a minuscule amount but it doesn’t bother me and I’m not going yo put any effort to change it

 

[The-Real-Deal82]

I don’t think it does. I only ever charge my iPhone overnight and always have done. I use the optimise feature too.

My iPhone 12 is from launch day and still at 100%.

 

[BigDO]

It does. Not a myth. Manage your battery at 45-75%, you will be fine.

You’re advising people to use 30% of their battery? Really?

 

[maerz001]

You’re advising people to use 30% of their battery? Really?

That’s what real lovers do. Just put „him“ in your gf 30% so that the one after you still gets all the pleasure