Several common bad habits of using lithium-ion batteries?

1) The battery is afraid of heat and cold. Many people like to put their mobile phones in their private cars and let them be exposed to the sun, or put thick clothes on the mobile phones. These habits will damage the battery life of mobile phones. The migration rate of lithium in the electrolyte and the electrode sheet is closely related to temperature, and fluctuations in temperature will significantly affect the technical performance of lithium-ion batteries (Figure 8). The normal operating temperature of lithium ion batteries is -20℃～+55℃. When the temperature drops below -20°C, the electrolyte in the battery will freeze, the internal resistance of the battery will become infinite, and the battery will become unusable. When the temperature rises to more than +55°C, the electrolyte will have side reactions and a large amount of gas will occur, and the resin adhesive in the electrode sheet will also deteriorate, resulting in the gradual aging and degradation of the entire battery, and even failure in a short time. It should also be noted that the operating temperature of lithium-ion batteries used in our digital products is generally limited to 0°C to 40°C. The operating temperature of lithium-ion batteries in smart phones and digital cameras is preferably 5°C to 35°C. Too high or too low temperature will make the battery core unable to play its best state, the power will continue to decrease, the power supply time is not as long as usual, and it may not be able to charge at low temperature. (2) In the manuals of digital products that do not require deep charge and discharge, manufacturers will indicate the number of cycles of charge and discharge of lithium-ion batteries, which are generally several hundred times. However, many people misunderstand its meaning and think that no matter how much power is used, the battery life will be consumed once by plugging and unplugging the charger, and the battery must be used up every time before recharging. In fact, one cycle of lithium-ion battery charging refers to a complete charging and discharging process. If we use only 10% of the power to charge, there will be no adverse effects, but it will delay the life of the battery and prevent over-discharge from affecting the battery life. . It is worth noting that even if the number of cycles of charging and discharging reaches the value given by the manufacturer, it does not mean that the battery will be damaged. This value is only a means to test the battery status, and we don't need to worry about numbers. Some people have done experiments, changing the standard 4.2V charging voltage to 4.1V, and testing the same type of battery for cyclic charging and discharging. The final result is that the charging and discharging life can be increased by 60%, replaced by 3.9V for testing, and the number of cycles It can be added several times, so if you want to delay the service life, the correct way should be slow charging, not deep charging. (3) The price of lithium-ion battery is not low when you buy it. Do you need to buy a few pieces when you encounter a discount? This is obviously undesirable, because first, the lithium-ion battery will automatically discharge, and the self-discharge rate per month is about 2%. If it is left unused for a long time, the battery will be damaged due to over-discharge. If you have a lot of digital products, Don't forget to charge them once every few months and keep 40% of the charge (Figure 9). It is easy to be overlooked that lithium-ion batteries are a product that is prone to self-depletion. Over time, the capacity of the battery will show irreversible physical degradation over time, from the day you buy it. At the beginning, no matter whether it was used or not, there was loss, and some products even reached 10% a year! This also reminds us that we must look at the date of manufacture when buying batteries, and it is best not to buy old products. (4) Don’t use strange chargers. Duck-egg-shaped mobile phone travel chargers. Chargers of more than ten yuan are common. They are easy to use and charge faster than the mobile phone’s own charger. But these chargers do not have a rigorous circuit design (Figure 10) and treat all types of batteries equally. According to the normal charging process, the lithium-ion battery charger must first be charged with a constant current, and when it is almost fully charged, it will be converted to a constant voltage, the current will gradually decrease, and the battery will be fully charged after a period of time. Inferior chargers use a constant current method. After the lithium-ion battery is fully charged, it continues to try to charge. If the protection circuit in the battery fails, the lithium-ion battery may swell, leak, or even catch fire and explode. Battery safety is very important. We should choose chargers of big brands. Products that have been certified and authorized by the manufacturer or have an outstanding reputation are very reliable, and their workmanship or protection circuits are significantly different from ordinary products. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. 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