Rocking chair battery Sony Corporation of Japan invented a lithium battery that uses a carbon material as a negative electrode and a lithium-containing compound as a positive electrode. In the process of charging and discharging, no metal lithium exists, only lithium ions, which is a lithium ion battery. When the battery is charged, lithium ions are generated on the positive electrode of the battery, and the generated lithium ions move to the negative electrode through the electrolyte. The carbon as the negative electrode has a layered structure, and it has many micropores. The lithium ions reaching the negative electrode are embedded in the micropores of the carbon layer, and the more lithium ions are embedded, the higher the charging capacity. Similarly, when the battery is discharged (ie, the process we use the battery), the lithium ions embedded in the carbon layer of the negative electrode come out and move back to the positive electrode. The more lithium ions return to the positive electrode, the higher the discharge capacity. What we usually call battery capacity refers to the discharge capacity. During the charge and discharge process of Li-ion, lithium ions are in a state of motion from positive electrode to negative electrode to positive electrode. Li-ionBatteries are like a rocking chair. The ends of the rocking chair are the two poles of the battery, and the lithium ion runs back and forth like a sportsman in the rocking chair. So Li-ionBatteries are also called rocking chair batteries.