How to correctly understand the overcharge phenomenon of lithium-ion batteries?

People often have a misunderstanding when charging: stick to the full state is the best. When the battery power rises from 100% to 99%, obsessive-compulsive disorder may kill you, but it is actually not recommended to charge your phone, especially after the phone is fully charged.

Lithium-ion batteries are not a panacea

Many older people always tell you when you get your first mobile phone that the new mobile phone must first complete all the discharge, then charge it for 12 hours, and then fully discharge it, repeating 3 times. In the beginning, you must be silly to do it honestly according to the words of the old generation, but in fact, smart phones that have used lithium-ion batteries no longer need such a laborious battery maintenance process.

Ni-MH batteries need to be charged and discharged many times. This battery has a strong memory. The charging and discharging process is also to make the Ni-MH battery reach the maximum charging limit. But now that mobile phones use lithium-ion batteries, there is no need to repeat such a complicated battery recall process. So will the lithium-ion battery always maintain the maximum charge limit?

The answer is definitely no. Although lithium-ion batteries are well-known for their uses, their power will lose an unpreventable upper limit during repeated battery cycles of charging and discharging. This is composed of one point and one point. In addition to normal charging, overcharging is the first evil.

How to understand the phenomenon of overcharging

Overcharge is actually easy to understand, that is, the phone continues to charge the phone battery when the battery is fully charged. At this time, let's call the phone overcharge. When the battery is fully charged, continuous charging will cause the structure of the negative electrode material to change, resulting in a loss of module capacity. However, the separation of oxygen and electrolyte will trigger a violent chemical reaction, and the worst result is an explosion.

They work very hard to prevent overcharging

In fact, most mobile phones now have IC protection. The charger itself also monitors voltage and current. Drip charging is commonly used in mobile devices to protect the battery and the user.

When charging using the USb interface, it is assumed that line loss is not considered. The USb charging port will negotiate with the mobile phone for charging and match the appropriate current to ensure that the mobile phone will not lose most of the current due to high current input. When the battery power is low, such as about 10%.

In addition to the overcharge protection of the mobile phone battery, there is another way to prevent overcharge by relying on the charging socket. It is necessary to supply power to the socket first to prevent overcharging in order to supply a stable voltage. The weaker the voltage, the current will be affected. Especially when the voltage at night in our country is unstable, it is very important to be able to ensure the stability of the output voltage of the USb interface. Generally speaking, the voltage of the USb charging port is 5V. Some USb charging ports that can intelligently distribute current will slightly reduce the voltage of the charging port when the mobile phone battery is close to being fully charged, thereby reducing the input current and alleviating the pressure on the battery.

These methods have a good effect on inhibiting the overcharging of the mobile phone, but the bottom is still because we have not unplugged the power, the mobile phone charging state, let the mobile phone continue to repeat the discharge and charging process, resulting in reducing the upper limit of the capacity.

Overcharging is not a trivial matter

The average lifespan of mobile phone users is really not a trivial matter. The battery life of the mobile phone directly affects the moment you use the mobile phone. Assuming that the mobile phone is charged arbitrarily, the battery will die when you trust it for less than a year.

If you can see that the current battery is a bit swollen, it may be an overcharge error. To be more serious, overcharging can even directly affect your safety. Those counterfeit machine batteries can guarantee that there will be no fireworks. If you want to prevent overcharging fundamentally, it seems that you still need to control it from time to time.

In the future, JUNLEE Energy, which has been committed to battery research and development, is a challenge and an opportunity. The R&D team of engineers will provide the world with more economical new energy batteries, and will improve lithium-ion battery technology to reduce the total cost.

JUNLEE Group is an integrated full power energy factory that specializes in Uninterruptible Power Supply (UPS), Lead-Acid Battery, Battery pack, EV battery, Energy Storage Battery, Energy storage power station, Power pack Gel battery, PV Inverter and Solar system.

Production capacity reach 200000 KVaH per month. Products apply to Electric vehicles,electric mobility, solar & wind energy storage system, UPS, backup power, telecommunication, medical equipment and lighting.

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