Can You Overcharge An iPhone? Dangers Of Charging Overnight

The iPhone is essentially a mini-computer with countless functions running in the background. As a result, the battery tends to drain very quickly. Naturally, you probably choose to charge your iPhone at night while you’re not using it. Although it’s a convenient option, are there any dangers to charging your iPhone overnight? And can you overcharge an iPhone?

You can’t overcharge an iPhone because it has an optimized battery that stops charging once it reaches 100%. If you’ve turned the battery optimization feature off, that’s OK but the constant charging will reduce the performance of the battery over time faster.

Many of us leave our phones plugged in on the nightstand so that we can start the next day at full juice, but, as you can see, that may not be the best option. Let’s take a closer look at the dangers of charging overnight and the ideal way to charge your iPhone.

What Happens if You Keep Your iPhone Charging After 100%?

Hand Charging battery on mobile smartphone

Many people worry that if they keep their iPhone charging after 100%, it’ll overcharge. In reality, it won’t. Modern smartphones have optimized batteries that stop taking in power once they reach capacity. 

However, if you leave your iPhone on the charger after it’s fully charged, it will inevitably start losing a little bit of power as it lies there — that’s just how batteries work. Once it loses a considerable amount of power, the charger will resume its duty and get the phone back to 100%.

When you let your phone stay on the charger for a lengthy period, this cycle of losing little bits of power and then recharging will carry on for hours. Leaving your iPhone on the charger for a long time doesn’t only consume unnecessary power from your outlet — increasing your utility bills in the process — but it also causes the phone to heat up.

Occasionally leaving your iPhone on the charger won’t cause any issues, but doing it every night may lead to premature deterioration of the battery’s performance due to the extra heat.

Is It OK to Charge Your iPhone Overnight?

As we just discussed, charging your iPhone overnight won’t overcharge the battery, but it could lead to other serious issues. Here are some of the dangers of charging your iPhone battery overnight:

Your iPhone Could Overheat

Overheating is perhaps one of the most significant problems you could face while charging your iPhone overnight. Lithium-ion (Li-ion) batteries, which are present in the iPhone (and almost all smartphones), contain lithium, which is very reactive. The heat it can generate could eventually lead to overheating, and your iPhone’s battery could catch fire as a result.

It might sound farfetched, but if you heard about the Samsung Galaxy Note 7 battery fiasco, you know that this isn’t fiction. HP also suffered a similar case recently and had to recall around 78,000 batteries that they feared might cause fire and burn damage.

So, is the world-famous iPhone really vulnerable? Apple certainly makes durable phones, but the battery still isn’t safe. Apple uses the same Li-ion technology that other manufacturers use. There have been numerous incidents of the iPhones catching fire because of their batteries.

That’s why charging your iPhone overnight isn’t such a great idea. If you don’t like taking risks, then charging your iPhone during the day is your best bet.

One more thing you need to keep in mind when charging your iPhone is the charger you use. The issue isn’t only with your regular cable iPhone charger. As it turns out, the iPhone’s wireless charging technology heats the phone even more.

All of this doesn’t mean you need to sleep with a fire extinguisher next to your nightstand. Experts suggest placing your iPhone on a plate or any other non-burning material if you charge your phone overnight, and they recommend using an official iPhone wireless charger (on Amazon).

Additionally, if you have to charge your iPhone overnight, a helpful safety tip would be to remove the phone’s case. Also, be sure not to place the phone under your pillow since it requires some “breathing room” to let the heat escape.

Apple recommends you use your iPhone within a temperature range of 0° to 35° C (32° to 95° F). Studies have revealed that some Li-ion batteries’ temperature may increase by up to 10° C (50° F) when overheated. So, keep that in mind while you charge your iPhone overnight.

You’re Shortening Its Battery Life

Every phone’s battery capacity declines after around 500-1,000 charge and discharge cycles. Basically, you complete a cycle when you use 100% of your battery. Let’s say you use 60% of your phone’s battery today, recharge it to 100%, and use another 40% the following day. That’s a cycle.

Theoretically, an iPhone’s battery can handle up to 500 cycles before its capacity starts to decline. Moreover, your battery grows old with time. This shouldn’t bother you that much if you change your iPhone every couple years.

But if your goal is to use your iPhone for a longer time than that, keep in mind that your battery will eventually lose its capacity and you will need to replace it.

At What Percentage Should You Charge Your iPhone?

According to experts’ opinions on Li-ion batteries, you should keep your iPhone battery at 80%. This is the optimal charge level for your iPhone or any other smartphone.

In truth, that remaining 20% is crucial for many users — it might be the difference between your iPhone lasting you through the day or not — but charging your iPhone overnight to 100% still isn’t advisable as it diminishes the battery capacity faster.

The good news is that Apple knows about this issue, and that’s why they made some significant changes with recent operating systems. Your iPhone can now charge to 80% and then stop charging despite still being plugged in.

Being that your smartphone is smart, after all, it will resume charging sometime before morning to reach 100% by the time you’re up. Kudos, Apple!

The iPhone doesn’t offer the best battery life out there but you can get the most out of the battery by charging it correctly. Here are some tips to keep your iPhone’s battery performing optimally and at maximum health for longer:

Charge Your iPhone Before or After Bed

If you have a period before bed when you’re free, use that time to charge your phone. You could charge it for an hour rather than use that time to browse the internet.

You could also charge your iPhone for an hour in the morning before you leave the house. And with the fast MagSafe wireless charger (on Amazon), your iPhone will reach the recommended 80% in no time.

Carry a Power Bank

Charging power bank

If you’re always on the move, consider getting a power bank, which you keep with you as a back-up. You can acquire a good, light-weight model for around $20. We recommend the Anker 313 Power Bank (on Amazon).

Keep Your iPhone Charger With You

It may sound obvious, but if you keep your charger with you, you won’t need to deal with a dead phone. You’ll be able to charge your phone in the car, office, or public places.

Short but frequent charges are better than one long charge. For example, you could charge the phone for a short period during lunch break and use that time to socialize instead!