Method and system for safely acquiring open-circuit voltage of lead-acid storage battery on line

The invention discloses a method and a system for safely acquiring open-circuit voltage of a lead-acid storage battery on line. The method comprises the following steps: connecting a management moduleto a connecting bus of a lead-acid storage battery pack and a charger in series; defining whether the lead-acid storage battery pack is fully charged or not, and if so, disconnecting a charging loopwith the charger by the management module; standing for a period of time at a standard temperature; respectively testing and recording the open-circuit voltage of each lead-acid storage battery by utilizing a battery monitoring module; and after the open-circuit voltage of each lead-acid storage battery is measured and recorded, the management module closing a charging loop of the charger, so thatonline open-circuit voltage acquisition is realized on the premise of ensuring the system safety, the safety of the lead-acid storage batteries is improved, and the safety of the station direct-current power supply system is e