The reason for the decrease of lithium-ion battery capacity and the introduction of repair methods

There are two common methods for repairing lithium-ion battery capacity decline: freezing method and overcharge and overdischarge method. 1. In the freezing method, the old cell phone lithium-ion battery that automatically shuts down is tightly wrapped with plastic wrap, and the package is as compliant as possible. There are three layers inside and outside to ensure that the battery is in a vacuum state. Then, wrap three layers of newspaper outside the plastic wrap to completely seal the lithium-ion battery. Put it into the freezer layer of the refrigerator. After 48 hours, take out the batteries, and remove the six layers of paper film wrapped one by one. The lithium-ion battery does not cause surface expansion or deformation due to freezing. After cooling for a period of time, then charge. 2. The overcharge method completely discharges the lithium-ion battery that is close to being scrapped, and then recharges the battery to activate it. The specific method is: deep discharge of the mobile phone is to achieve a deeper recharge by depleting the internal electric energy, which requires some unconventional methods. Use a specific device to connect the mobile phone to a small low-voltage light bulb, and the power inside the battery will be transferred to the small light bulb until all is discharged. The mobile phone slowly runs out of power through a lower voltage. Under normal circumstances, if the mobile phone is connected to the rated voltage of less than 3.6 volts, it will automatically shut down. After the battery is discharged, the recharged mobile phone battery can be used for a longer time. The above methods, whether effective or not, can only be a temporary stopgap measure. As long as the capacity of the lithium-ion battery drops, it is difficult to restore to the original state, so if all methods are ineffective, buy a new one. The battery is more reliable. Professor Rachid Yazami of NTU said that his invention can restore the old lithium-ion battery to 95% of its capacity within 10 hours, and can repeat the recovery operation on the same battery every few years, which will greatly improve electronic equipment. And the service life of lithium-ion batteries used in electric vehicles, at the same time, it can greatly reduce the waste of lithium-ion batteries and make lithium-ion batteries more environmentally friendly. After the invention was published, industry giants including Apple, Samsung and Panasonic have expressed strong interest in this invention. The invention adds a third electrode between the existing two electrodes in each lithium ion battery. The third electrode discharges the remaining lithium ions from one electrode to the other, thereby removing the influence on the battery performance and preventing the battery from storing more The impurity content of electronics has been successfully tested on a prototype smartphone. However, for battery manufacturers, this may not be a good thing, and it is likely to deliberately delay the large-scale adoption of this technology. Reasons for the decrease in the capacity of lithium-ion batteries 1. The battery core is aging and decayed. 2. The self-discharge rate is different, resulting in unbalanced battery cells in series, which will eventually reduce the capacity of the lithium-ion battery and become less durable. 3. In the process of battery use and charging and discharging, vulcanization phenomenon will affect the battery capacity. The vulcanization performance of the battery is: the battery itself is low in voltage, it will be full after charging, and it will be gone after discharging. The softening of the battery is manifested as: the liquid inside the battery is turbid and black. The capacity of the battery decreases, and the lead powder falls off after a long period of time. 4. Improper charging in summer and winter. The battery charging voltage is inversely proportional to the ambient temperature, so the summer temperature is high, and the overcharge of the lithium-ion battery causes the battery to lose water, which causes the battery to swell and deform. In winter, the driving mileage decreases due to undercharging. 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 post: What are the common failure performances and failure mechanisms of lithium-ion batteries?