What is the overcharge phenomenon of lithium battery?

Analysis of Lithium Battery Overcharge Phenomenon Lithium battery charging methods: fast charge, slow charge, trickle charge, constant current charge, etc. Overcharge means that the voltage during charging is higher than the charge cut-off voltage, generally 4.2V for lithium batteries. The voltage level determines whether the battery is overcharged, and has nothing to do with the charging time. Generally, due to the battery management chip in the charger or mobile phone, the highest output voltage to the positive and negative ends of the battery is 4.2V. Even if it exceeds, there is a protection board built into the lithium battery. This means that the voltage to the cell will never exceed 4.2V. No matter how long it is charged, it will not overcharge. Overcharging is actually easy to understand, that is, the mobile phone continues to charge the mobile phone lithium battery when the battery is full. At this time, we say that the mobile phone is overcharging. Continuing to charge the battery when the battery is full will cause changes in the structure of the positive electrode material, resulting in a loss of capacity, and the decomposition of oxygen and electrolyte will cause a violent chemical reaction, and the worst result will naturally be an explosion. In fact, most mobile phones now have IC protection. The charger itself will also monitor the voltage and current. In order to protect the safety of storage batteries and users, trickle charging is often used on mobile devices. When using the USB port for charging, if the loss on the wire is not calculated, the USB charging port will negotiate with the mobile phone to charge and match the appropriate current. In this way, it can be guaranteed that the mobile phone will not lose most of the current due to the high current input. The battery power is low, such as about 10%. At this time, the efficiency of charging the lithium battery is the highest, and the current reaches the highest state. With the increase of capacity, the current required by the mobile phone will gradually decrease. When the last 10% to 20% of the remaining battery reaches full power, the mobile phone will even request a small pulse current for charging, so as to achieve the purpose of protecting the battery. The charging method is also called trickle charging, which is the current mainstream mobile phone charging method to reduce the loss of the upper limit of the electric capacity and extend the battery life. For ordinary mobile phone users, overcharging is really not a trivial matter. The lifespan of the mobile phone’s lithium battery directly affects the time you use the mobile phone. If you let the mobile phone overcharge wantonly, I believe that the battery will be needed in less than a year. Died prematurely. Disclaimer: Some pictures and contents of articles published on this site are from the Internet. If there is any infringement, please contact to delete.