Is it harmful to leave your smartphone charging at night?

Many people leave their smartphone plugged in overnight. However, this can harm the battery - at least in some cases.

is it harmful to leave your smartphone to charge at night

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To begin with, it should be said that modern smartphones are insured against overcharge or deep discharge. The whole process of charging the device is answered by the controller, which will automatically stop supplying current when the battery is fully charged and will not allow it to be completely discharged by turning off the smartphone with 1-4% of the remaining charge. Therefore, modern smartphones are less whimsical in the charging process and are able to “forgive” users a lot of mistakes.

Charging your smartphone at night: is it harmful or not?

Nevertheless, it is still not worth approaching the charging procedure carelessly. And first of all, this applies to the night charging so beloved by many. Yes, leaving your smartphone on charge overnight, and getting a fully charged gadget in the morning is very convenient. But this is still harmful to the smartphone’s battery, although not as harmful as it used to be.

The thing is that everyone, including a modern battery, has a certain resource. This is not some kind of timeline, but the so-called number of charge-discharge cycles. On average, the battery is designed for 500-550 such cycles, after which the degradation process begins to appear – the battery gradually loses its ability to hold a charge. For example, if your smartphone battery has a capacity of 4000 mAh, then over time you can only charge it up to 3400 mAh, then up to 3000 mAh, and so on.

If you leave your smartphone plugged in overnight, most often it will fully charge after a couple of hours. From this point on, the battery automatically stops charging. However, when the battery level drops slightly, the smartphone will recharge to 100 percent again, and its life will drop slightly. Each night, this “little bit” will greatly speed up the process of battery degradation, and the battery life of your smartphone will decrease.

On the Internet, you can find tips to keep the battery charge of your smartphone between 50 and 80 percent. And this can really help to slightly extend its service life up to 1000-1500 cycles against the standard 500. However, it should be understood that in this case the smartphone will have to be charged much more often. Therefore, the real gain in time will not be 3 times, but much more modest.

How to properly charge a smartphone battery?

It is best to charge your smartphone in the evenings. While you are sitting in front of the TV in the evening and watching a movie or football, your mobile phone may well be charging. As soon as the battery status indicator starts to show between 70 and 90 percent, disconnect the charger from the mains.

Most modern smars? ...
Most modern smartphones have batteries with a capacity of about 5000 mAh, and 80% of the charge is enough for them to last a day.

True, all the advantages of a large battery are lost with rational charging.

In theory, the smartphone can be turned off overnight to conserve battery power and charge it less frequently. Moreover, you will hardly need it at night. If you also use your mobile phone as an alarm clock, then it is best to switch it to “Airplane mode”, in which the power consumption of the device will be noticeably reduced. However, here you don’t need to invent anything on your own. Many smartphone manufacturers have provided night modes, which are precisely designed to minimize power consumption when you are sleeping and not using your phone.

Is fast charging harmful?

A rare modern smartphone does not support fast charging technology, but what is it? The standard smartphone power adapter has an output power of up to 10W. It consists of a voltage of 5V and a current strength of up to 2A. Anything above these indicators can already be called fast charging.

The fast charging process takes place in several stages. In the first of them, the smartphone is charged with high currents – the charging speed is maximum. After reaching the level of charge determined by the developer of the technology (usually 70-80 percent), it begins to recharge with low currents – the charging speed slows down. This reduction in amperage is exactly what is needed to prevent overheating and damage to the battery.


Moreover, some high power fast charging technologies use two-cell batteries with independent charging to reduce the charging power per cell while maintaining high charging rates. For example, 120W fast chargers work exactly according to this principle.

In other words, manufacturers have done everything to ensure that fast charging does not lead to increased battery wear, and, in our opinion, its use is quite safe. Although, if you do not trust these conclusions, then you can easily turn off the fast charging of any smartphone yourself.