How to correctly understand the overcharge problem of lithium batteries?

Everyone usually has a misunderstanding when charging: it is better to insist on a fully charged condition. Perhaps for obsessive-compulsive disorder, when the battery power jumps from 100% to 99%, it will kill him, but in fact, it is not recommended by energy storage battery manufacturers to keep the mobile phone in a charged state. The battery of the mobile phone can't stand the tossing because it continues to charge after the device is fully charged. Lithium batteries are not omnipotent. Many older generations always tell you when you get a mobile phone that the new mobile phone must be fully discharged, then charged for 12 hours, and then fully discharged. This needs to be repeated 3 times. If you are a bit silly at first, you must do it honestly according to the words of the older generation, but in fact, smart phones that already use lithium batteries no longer need such a laborious battery maintenance process. It is the nickel-metal hydride battery that needs to be repeatedly discharged and charged. This kind of battery has a strong memory. The repeated charging and discharging process is also to allow the nickel-metal hydride battery to achieve a larger charging limit. But today's mobile phones all use lithium batteries, there is no need to repeat such a messy battery memory process. So, will lithium batteries always adhere to a higher power limit? The answer is definitely no. Although lithium batteries are known for their long-term use, the unavoidable upper limit of their power consumption will be lost during the repeated charging and discharging process of the battery. This loss is built up over time, and the factors that constitute the loss are in addition to normal charging. It is the culprit of the great evil. How to understand the phenomenon of overcharging Overcharging is a good idea, that is, the mobile phone continues to charge the mobile phone battery when the battery is full. At this time, the energy storage battery manufacturer claims that the mobile phone is overcharging. When the battery is full, continuous charging will cause the material structure to change, resulting in a loss of capacity, and the decomposition of oxygen and electrolyte will cause a violent chemical reaction. The worse result is naturally an explosion. Usually knowledge also tells us that the better way to keep the battery is at room temperature and in a boring place, whether it is a nickel-hydrogen battery or a lithium battery is the same. When overcharge occurs, there is no doubt that a lot of heat energy converted by the current will be emitted, and then the lithium battery is reacting with the electrolyte, which consumes the large capacity of the lithium battery. When the heat accumulates to a certain degree, it will catch fire and burst. Events are likely to happen. Faced with such a low-security job, natural mobile phone manufacturers and charger manufacturers will not sit idly by. When users have security problems, they are the ones who are going to lose their luck. Therefore, there are a lot of carefulness when charging mobile phones, especially the current mainstream mobile phones and chargers that use USB ports for charging. Overcharging is not a trivial matter. Energy storage battery manufacturers tell you that overcharging is really not a trivial matter for ordinary mobile phone users. The battery life of the mobile phone directly affects the moment you use this mobile phone. Overcharge, I believe that the battery will die in less than a year. If you can see that the reverse side of the battery is now slightly arched, it may be the fault of overcharging. Going bigger, overcharging and even directly affecting your safety, the defective batteries of those counterfeit phones may not be allowed to set off fireworks or something. If you want to prevent overcharging fundamentally, it seems that you still have to control your hands all the time. In order to prevent overcharging, they are really hard work. Most mobile phones now have IC protection. The charger itself also monitors the voltage and current. In order to maintain the safety of batteries and users, energy storage battery manufacturers usually choose trickle charging on mobile devices. When using the USB port for charging, if the wire loss is not calculated, the USB charging port will negotiate with the mobile phone to charge and match the appropriate current. This way, it can ensure that the mobile phone will not lose most of the current due to high current input. The battery power is low, such as around 10 percent. At this moment, the power to charge the battery is higher, and the current has reached a higher level. With the increase of power capacity, the current requested by the mobile phone will gradually decrease. When the remaining 10% to 20% reaches full charge, or even when the phone is at the right time, it is requested to charge with a small pulse current, and then reach the intention of maintaining the battery. This charging method is also called trickle charging. It is the current charging plan for mainstream mobile phones to reduce the loss of the upper limit of the electric capacity and extend the battery life. In addition to providing overcharge maintenance for mobile phone batteries, there is another way for energy storage battery manufacturers to rely on charging sockets to prevent overcharge. To prevent overcharging, the socket must first supply a stable voltage. The greater the voltage fluctuation, the current will also be affected. Especially in China, the voltage fluctuates frequently at night. It is very important to ensure the stability of the output voltage of the USB port. Generally speaking, the voltage of the USB charging port is 5V. Some USB charging ports that can intelligently distribute current will slightly lower the voltage of the charging port when the mobile phone battery is close to the full charge condition to reduce the input current to reduce the battery pressure. These methods have a good inhibitory effect on mobile phone overcharging, but in the final analysis, it is still because we did not unplug the power when the mobile phone was fully charged, so that the mobile phone continued to repeat the process of discharging and charging, resulting in a reduction in the upper limit of the capacity. . Disclaimer: The articles published on this site are all from the Internet and do not represent the views of this site. If there is any infringement, please contact to delete WeChat: Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact delete A: Development Status of Domestic Lithium Battery Management System (BMS)