It is better not to charge the cold smartphone under freezing immediately

In winter, devices such as iPhones and tablets are often exposed to cold environments.Sometimes you carry your iPhone when skiing, or you may put a new tablet outside the entrance.The reason is that there is something important to let me know about devices that are exposed to the cold.That is, when the device equipped with a lithium -ion battery is cold below freezing, do not charge it.

What happens if you charge a lithium -ion battery under freezing?

In this case, there are two major problems.The first problem is that charging a cold lithium -ion battery under freezing reduces the capacity of the entire battery.Any battery decreases with the maximum capacity over time.This is a phenomenon called chemical aging.However, when charging under freezing point, the capacity will decrease at that point, and it will look like a much older battery than it actually.I don't like the device where the battery runs out immediately, even though it's a new one.The second problem is even more serious, which can be dangerous for users.When charged under freezing, the battery becomes like a timed bomb.In other words, the battery can literally explode.It does not necessarily explode immediately, and it does not always explode, but it will be a fate that will break down somewhere in the future.This information is a very detailed article posted by user Metacollin to the Electrical Engineering Forum.It is a post that explains in detail, including the lithium -ion battery mechanism, so if you want to know the details, please read the post.But here, I will explain it very easily to organize my head.

Reasons why the lithium -ion battery should be cold under freezing

The lithium -ion battery has two pides, an anode and a cathode, and plays a role like a lithium -ion sponge.When the battery is used, the lithium moves from the anode to the cathode.If most of the lithium exit the anche and accumulate in the cathode, the battery will be "discharged" and the device will turn off.While charging, the lithium moves from the cathode to the anode.If most of the lithium returned to the anche, the device would have been charged.Do you know so far?By the way, if the battery is charged under freezing, the cathode does not "absorb" lithium, and the lithium covers the cathode.This lithium aggregate gives a great stress on the cathode, and when the cathode expands naturally during charging, the lithium coated with the cathode enters inside.As a result, it leads to an unexpected failure of the battery.On the contrary, in the process, the cathode and the anche may come into contact, and in the worst case, it may ignite or explode.

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