A lithium-ion (Li-ion) battery functions based on the movement of lithium ions between the anode and the cathode as shown in Figure (a). The most common setup involves a graphite anode and a metal oxide cathode, with a lithium salt electrolyte in between. During discharge, lithium ions move from the graphite anode, through the electrolyte, and intercalate into the metal oxide cathode. At the same time, electrons released from the anode travel through the external circuit, providing power to devices, before rejoining the lithium ions at the cathode. The charging process reverses this movement, with lithium ions deintercalating from the cathode and returning to the anode . .