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. The more lithium ions are embedded, the higher the charging capacity. Likewise, when the battery is discharged (that is, the process in which 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 returned to the positive electrode, the higher the discharge capacity. What we usually call battery capacity refers to the discharge capacity. During the charging and discharging process of Li-ion, lithium ions are in a state of motion from positive electrode → negative electrode → positive electrode. Li-ion Batteries is like a rocking chair, the two ends of the rocking chair are the poles of the battery, and the lithium ion runs back and forth in the rocking chair like an athlete. So Li-ion Batteries are also called rocking chair batteries.
