Analyze the charging and discharging principle of lithium batteries

The principle of charging and discharging lithium batteries The working principle of lithium batteries is the principle of charging and discharging. When the battery is charged, lithium ions are formed at the positive electrode of the battery, and the resulting lithium ions pass through the electrolyte to the negative electrode. Carbon is the negative electrode and has a layered structure with many micropores. Lithium ions reaching the negative electrode are inserted into the micropores of the carbon layer. The more lithium ions are inserted, the greater the charging capacity. Similarly, when the battery is discharged (the process we use the battery), the lithium ions embedded in the carbon of the negative electrode will come out and return to the positive electrode. The more lithium ions return to the positive electrode, the greater the discharge capacity. The battery capacity we usually call refers to the discharge capacity. It is not difficult to see that during the charging and discharging process of lithium batteries, lithium ions are in a state of movement from the positive electrode to the negative electrode and then to the positive electrode. Let us compare the lithium battery to a rocking chair. The two ends of the rocking chair are the two poles of the battery. Lithium ion, like an excellent athlete, moves back and forth on both ends of the rocking chair. Therefore, the experts gave the lithium battery their favorite name: rocking chair battery. Lithium battery charging control is divided into two stages during the charging and discharging process. The first stage is constant current charging. When the battery voltage is lower than 4.2v, the charger charges with constant current. The second stage is the constant voltage charging stage. When the battery voltage is 4.2V, due to the characteristics of lithium batteries, assuming that the line voltage is high, it will be damaged. The charger will be fixed at 4.2V and the charging current will gradually decrease. When the current decreases, the required value (Usually set the current 1/10), blocking the charging circuit, indicator, fully charged fully charged. Excessive charging and discharging of lithium batteries can cause permanent damage to the positive and negative electrodes. Excessive discharge leads to depressions in the negative carbon sheet structure, and the depressions will constitute a charging process that lithium ions cannot penetrate; excessive charging will cause lithium ions to be embedded in the carbon structure of the cathode, and some of them can no longer be released. 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. Previous: About the choice of lithium batteries and solid-state batteries