The battery of the mobile phone is not fully charged when I go out or the battery is 90% charged when I am going to sleep at night, do I need to continue to charge it? In fact, for the battery, under the normal state of the mobile phone, both of them are not very harmful.

It must be compared, that is, overcharging is harmful, because overcharging will cause your battery's lithium ions to form lithium crystals near the negative electrode, which may penetrate the positive and negative separators inside the battery and cause a short circuit. The result of the short circuit is serious-fire, explosion. But unfortunately, you basically have no chance of overcharging, unless there is a problem with your phone. The built-in power management system of the mobile phone monitors the voltage of the battery of the mobile phone (usually a single cell) to ensure that after the voltage reaches the full charging voltage condition, it stops sending the charging request, and then cuts off the charging process, so there is no harm.

What are the hazards of unsatisfactory charging? In fact, there is basically no. One of the advantages of lithium batteries is that there is basically no memory effect, and the calculation of the number of cycles is based on the full charge as the test condition, so it does not matter if the charge is not satisfied, and it is not much harmful. The number of cycles is now basically over 1200.

In fact, the most harmful thing is over-discharge, which means that your phone’s battery level is lower than 20%, especially lower than 10%. If you continue to play with your phone at this time, it will be because the lithium ion of the battery is in the process of detaching from the negative electrode. There is a risk of the negative carbon frame collapsing, causing it to not be able to insert the same amount of lithium ions next time, that is, the actual charging power becomes less and the battery becomes unusable.

Therefore, the best way to protect the battery of a mobile phone is to charge it when the battery is below 20%.