The present disclosure provides a quick charging method and a quick charging system. A second controller sends a quick-charging request to a first controller. The first controller feeds back a quick-charging permission command. The second controller sends a notification request for obtaining a voltage value of a cell. The first controller obtains the voltage value by a cell connector, and sends the voltage value to the second controller. The second controller finds a current regulation instruction matching a threshold section that the voltage value falls within from a threshold section table, and send a current regulation instruction to a regulation circuit. The regulation circuit adjusts a current and outputs a power supply signal of which the current is regulated.