Is It Bad to Leave Your iPhone Charging Overnight in 2024?

You’ve probably heard that it’s not okay to leave your iPhone charging overnight. Surely you've heard the opposite as well – that it’s perfectly fine to do so. 

So where do we draw the thin line between myth and truth?

This article will demystify this topic – you’ll find out if it really is bad to leave your iPhone charging overnight. You’ll learn some cool stuff along the way, including practical tips to prolong your phone’s battery life.

So, without further ado, let’s jump right in.

Cell Phone Batteries – What Are They like in 2021?

A decade ago, there were mobile phones that could go on for a week without charging. Sure, you couldn’t check your Facebook or play anything more complicated than Snake and Tetris, but still. 

Those models had a NiMH cell phone battery. It was replaced by the Lithium-Ion batteries we use today, since the latter were quicker to charge.

Naturally, the iPhone is more than a flashlight that also happens to ring people, but still, the difference is obvious. Today you’ll be lucky if your smartphone manages to survive two days without charging it. 

So why should you care about NiMH batteries, since it’s 2021 and smartphones don’t use that mobile phone battery anymore?

The reason is that NiMH batteries are responsible for almost every myth about iPhone charging. The funny thing is, there has never been an iPhone with a NiMH battery. 

Today, some people continue to think they can overcharge their phones, thus destroying the battery. Not only that, but they believe using their phone while charging is also a bad thing. Last but not least, some believe that iPhone batteries have “memory". The memory effect means that if your phone is only partially discharged and you charge it, the battery will “remember” the smaller capacity it needs to reach 100%, thus shrinking the battery’s capacity. Which was true for most NiCD and NiMH batteries, but that’s not the case with Li-Ion batteries..” And yeah, there’s absolutely no reason on Earth why you should put your iPhone in the freezer. In fact, it’s dangerous for your phone.

Rest assured – these are just myths in 2021. These issues troubled the older type of mobile phone battery, but continue to mislead iPhone users even today. 

Nevertheless, there are some problems with the Li-Ion batteries as well, and now we’ll check them out. That’s how you’ll know if your iPhone charger damages your phone’s battery while you are asleep.

Why Is It Bad to Leave Your iPhone Charging Overnight?

So far, there are more than 1.5 billion iPhones with Li-Ion batteries worldwide. These batteries are better than NiMH, but they aren’t flawless. Here are some issues you may experience with your iPhone battery because of its nature.

Li-Ion Batteries Generate a Lot of Heat

This would be one of the notable problems you may face while charging your iPhone overnight. Li-Ion batteries are very practical, but lithium is a very reactive material. The heat it could generate can eventually lead to overheating, and the battery could catch fire. 

If this sounds unbelievable, let me remind you of the Samsung Galaxy Note 7 battery fiasco. Moreover, HP suffered a similar issue recently and had to recall around 78,000 batteries, which may cause “fire and burn damage.”

Now.

I know what you are thinking.

Since you are an iPhone user, this couldn’t happen to you. 

Apple does make durable phones, sure. Some may bend a bit, but the battery is safe.

Unfortunately, this isn’t quite true. Apple uses the same Li-Ion technology as other manufacturers. There have been several incidents with iPhones catching fire because of their batteries. 

So this is one of the reasons why charging your iPhone overnight is not a great idea. If you like to avoid all risks, even those with the tiniest of odds - then charging it during the day is your best bet.

The problem isn’t only with your traditional iPhone charger. The iPhone wireless charging technology heats the device even more. Just something to keep in mind when you’re charging your phone. 

This doesn’t mean you should sleep with a fire extinguisher next to your charger. 

This may sound dumb to most of you, but experts suggest using a plate or other non-burning material to place your iPhone while charging overnight. Especially if you use a standard Qi iPhone X wireless charger. It makes a lot of sense when you think about it.

According to Apple, you can use your iPhone at a temperature range of 0° and 35° C (32° to 95° F). A study from Battery University shows that some Li-Ion packs’ temperature may rise with up to 10° C (50° F) (the average is about 5° C (41° F)). That’s why you should keep this in mind while charging your iPhone overnight when you can’t monitor its temperature. 

You should be especially careful if you use an iPhone wireless charger since it generates more heat than the conventional one. 

In the fewest words possible – heat is bad for your iPhone’s battery. Period.

Charging Your iPhone Overnight Shortens Its Battery Life

Every mobile phone battery’s capacity diminishes after 500-1000 charge-discharge cycles. You complete a cycle when you use 100% of your battery. 

For example – you use 40% of your phone’s juice today, then you recharge it to 100%, and the next day you use another 60%. That’s one cycle. 

In theory, an iPhone’s battery could last up to 500 cycles before its capacity starts to fall. Not only that but your battery ages with time on its own. If you change your iPhone every year or two, you shouldn’t care that much. Still, if you intend to use your iPhone for a longer period than that, keep in mind the battery will inevitably lose its capacity in time.

So Why Is Charging Your iPhone Overnight a Bad Idea, in Terms of Cycles?

I know it’s great to wake up and have a 100% juice to carry you through the day. However, your cell phone battery needs only about two hours to recharge itself completely. 

So what happens in the hours between the time your phone reaches 100%, and the moment you unplug it from the iPhone charger?

See, your iPhone is constantly draining its battery due to several operations it performs even when you aren’t using it. That’s why your iPhone charger is constantly “trickle-charging” your battery, which slowly but surely depletes the number of cycles your battery has at full capacity.

Here’s what happens to your battery during the night:

The green chart represents the overnight charging of an iPhone.

You can check your battery’s capacity via the “Battery Health” tab on your iPhone. So overcharging it at night will inevitably diminish its capacity over time.

See the maximum capacity? The iPhone battery has 12% less capacity to store power, due to frequent overnight charges. And a 100% charged phone isn’t always the best thing.

How Much Juice Do You Actually Need? 

When you are charging your iPhone overnight, it’s a 100% ready to go through the day. But do you really need that 100% from your cell phone battery? 

Experts’ opinions on Li-Ion batteries are unanimous – you should keep your iPhone charged at 40%-80%. This is the optimal charge level of your iPhone (or any other smartphone for that matter) to prolong its battery life. 

Sometimes this 20 % could mean the difference between your iPhone lasting through the day or not.  Still, charging your iPhone overnight to 100% often will decrease its battery capacity faster. 

Thankfully, Apple knows about this issue. That’s why they announced their iOS 13, which will take care of this. Your iPhone charger will charge your iPhone to 80%. Then your iPhone will still be plugged in but not charging. 

Since your smartphone is after all, smart, it will start charging again sometime before your alarm, to reach 100% by the time you wake up. Thumbs up, Apple.  

Now that you know it’s not so good to keep your iPhone charged at 100% let’s have a look at the other extreme. 

Should You Completely Discharge Your iPhone?

Once again, a debatable topic. Some people believe it’s healthy to discharge your battery completely now and then. 

Still, now that you already know that a Li-Ion cell phone battery doesn’t have the “memory” of a NiMH one, there’s no need to discharge it. In fact, you shouldn’t let your battery reach 0%. Here’s why:

First of all – fully discharging a Li-Ion battery may damage it, thus reducing its capacity.

Here’s the deal:

If your cell phone battery reaches 0%, chemical reactions start to affect the electrodes in your battery. The safety circuit brakes and there’s a risk that you won’t be able to even recharge your battery.

Secondly – if you don’t recharge your phone as soon as possible, the battery may become incapable of holding a charge or its efficiency will decrease.

What to Do If Your iPhone Won’t Turn on Due to a Dead Battery?

Well, the obvious answer is to change the battery.

Since the iPhone comes with a built-in battery, you can’t replace it yourself. Let me rephrase that for our Russian readers – you shouldn’t change it by yourself. 

Once the battery dies, you have to go to a licensed store to get a replacement. 

The thing is, not only you’ll lose time taking your phone to the store to get the replacement – you should take the prices into account as well.

Because of Apple’s battery fiasco in 2017, the company lowered its replacement fees for a period. Nevertheless, prices went up again since the 1st of January, 2019. Today you can get a battery replacement for $69 for the iPhone X (which was the best selling smartphone in Q1 2018) and its siblings – XS, XS Max, and XR. If you own an older iPhone, its new battery will cost you $49.

Apparently, most iPhone users prefer to spend some cash instead of charging their iPhones correctly.

How Many People Are Charging Their iPhones Overnight?

Most of us don’t particularly care that much about our phones’ longevity. 

Unfortunately, there isn’t an official statistics about how many people use their phone’s battery charger at night. Still, we found a poll with more than 16,000 answers which sheds some light on the question.

Source of the poll: TheJournal.ie. Chart by the author.

So, that’s what most people do. It doesn’t come as a surprise since most smartphone users buy a new phone every 21 months. For that period, you probably wouldn’t notice any significant decrease in your smartphone’s battery capacity.

However, if you intend to use your phone for a longer period, you should consider unplugging the Apple iPhone charger at night. Besides, you don’t really need the phone in your bedroom.

How to Avoid Charging Your iPhone Overnight? Practical Tips

So if you are not charging your iPhone at night, how can you go a whole day without losing power?

The iPhone surely isn’t the phone with the best battery life out there. Still, you can extend it by charging it right. Here are several tips to keep your iPhone’s battery at maximum health for longer. 

If you want to keep your iPhone healthy, charge it right – that means not at night.

Tip #1 – Stop Charging Your iPhone Overnight

Most people have at least an hour between waking up and going to work. That’s why you could plug in the iPhone charger once you wake up. 

By the time you eat your breakfast, drink your coffee, and take a shower – your iPhone should reach a healthy 70%-80%, which is more than enough to get you through the workday.

Tip #2 – Have an iPhone Charger Everywhere

I know this may sound like an awful lot of trouble, but it actually isn’t. 

It’s easy to place a charger in the office and in your car so you could plug it in from time to time. If you have a lunch break, that would be a perfect time as well. Short but frequent charges work way better than a single long charge. Besides, you’ll have more time to do some old-school face-to-face socializing with your co-workers. 

Tip #3 – Use a Portable iPhone Charger (A.K.A. a Power Bank)

If you are usually on the move, a power bank could be a great solution. You can get a decent one for $15-$30. 

And since the iPhone 7 is the most popular smartphone in the US, you could get an iPhone 7 wireless charging case for as low as $18 on Amazon. 

There are thousands of devices out there that could charge your iPhone while on the go. Take advantage of them – your iPhone’s battery will thank you. 

Conclusion

Quite often, it’s like we are glued to our smartphones. No matter if it’s for browsing the Web, watching Youtube videos, playing games or making calls and texting. 

That’s why we barely have time to leave them for a while to recharge their batteries. So, once the day is over, we leave them plugged in on the nightstand, and that’s that. We start the next day at 100% juice, and we are good to go.

Unfortunately, by doing so, we are slowly killing their batteries, thus diminishing our phones’ lives. 

If you plan to use your iPhone for a year or two – you shouldn’t care how you charge the device. Still, if you’re emotionally attached to your phone or you don’t plan to change it soon, consider taking care of it the right way.

To summarize everything said so far – short, frequent recharges work better than fully charging your iPhone overnight. That way you can enjoy your iPhone for longer.

See you next time!