During the charging process, some lithium ions in lithium iron phosphate are removed and transferred to the negative electrode through the electrolyte, which is embedded in the negative electrode carbon material; At the same time, electrons are released from the positive electrode and reach the negative electrode from the external circuit, maintaining the balance of chemical reactions. During the discharge process, lithium ions detach from the negative electrode and reach the positive electrode through the electrolyte. At the same time, the negative electrode releases electrons, which reach the positive electrode from the external circuit and provide energy to the outside world.