Analyze the basic concepts of mobile phone lithium batteries

Analyze the basic concept of mobile phone lithium battery Today's mobile phones are basically equipped with lithium batteries, so the following lithium battery charging is common sense. Ni-MH batteries are different, not here. 1. The nominal voltage of the lithium battery is 3.7v (3.6v), and the charging cut-off voltage is 4.2v (4.1v, according to the different design of the battery brand). (Lithium battery manual reads: lithium ion secondary battery) 2.Lithium battery requirements (GB/T182872000 specification): the first constant current charging, that is, the necessary current, and the battery voltage and the charging process gradually increase, when the battery voltage 4.2V, reaching 4.1V), constant voltage charging, instead of voltage, the fullness of the battery that must be charged with current and constant current will continue to gradually decrease according to the charging process. When it decreases to 0.01 degrees Celsius, the charging is stopped. (C is a way of displaying the nominal capacity of the battery to the current. For example, the battery has a capacity of 1000mAh, and 1C is a charging current of 1000mA. Note that mA is not mAh, and 0.01C is 10mA.) Of course, the general term is 0.01c5a, I Simplified. 3. Why 0.01c is considered the end of charging: This is the rule of the national standard GB/t18287-2000, and it was also discussed. In the past, we generally ended with 20mA, which is also the regulation of the Ministry of Posts and Telecommunications Industry Standard YD/t998-1999, that is, no matter how large the battery capacity is, the stop current is 20mA. The national standard stipulation of 0.01C helps to charge more abundantly, which is beneficial for the manufacturer to pass the judgment. In addition, the national standard stipulates that the charging time should not exceed 8 hours, that is, even if it does not reach 0.01°C, the charging will end after 8 hours. (A high-quality battery should reach 0.01C within 8 hours; a poor-quality battery is meaningless) 4. How to distinguish whether the battery is 4.1v or 4.2v: The customer cannot distinguish, this should be based on the battery manufacturer's product manual. Some brands of batteries are 4.1V and 4.2V in general, such as Au0026TB (Toshiba), domestic manufacturers are 4.2V, but there are exceptions, such as Tianjin Lishen is 4.1V (but now also 4.2V). 5. What happens if you charge the 4.1v battery to 4.2v? It will increase the battery capacity and make it feel very easy to use. Suppose it drops from 500 to 300. For the same reason, overcharging the 4.2v battery will also shorten the battery life. Lithium batteries are very fragile. 6.Because of the battery protection board, can we rest assured: No, because the protection board of the cut-off parameter is 4.35v (fortunately, poor 4.4 to 4.5v), the protection board is the assumption of tangse, assuming that every time it is overcharged, the battery is fast Will rot. 7. How much charging current is appropriate: In theory, the smaller the battery, the more advantageous it is. But you can't wait three days to recharge the battery. The national standard for low-battery charging is 0.2C (regulated charging standard). For example, a battery with a capacity higher than 1000mAh is 200mA, so we can estimate that the battery can be fully charged in more than 5 hours. (Capacity mAhu003dcurrent mA×hourh) 8. How much charging current can the lithium battery withstand: The manufacturer can be very high, but the national standard is 1C elevation angle multiplier, also take the battery as an example, it can be fully charged in more than 1 hour. Can the battery withstand such a large charging current? The current lithium battery is a trivial matter. There is no national standard for the charger, but it implements the industry standard YD/T9981999/2 of the Ministry of Posts and Telecommunications, which stipulates that the charger current should not be greater than 1C. 9. What is the rule of life: Simply put, the capacity of the battery drops to 70% after N times of 1C charging and 1C discharge, and N at this time is the lifespan. This is not to say that you can use it 300 times, but you cannot use it 301 times. The national standard service life shall not be less than 300 times. The conditions we usually use are not as harsh as those used for testing, so the life span will be longer. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: How about the acceptance test of lithium battery UPS and UPS battery?