Yes, solar panels can discharge a battery under certain conditions, especially at night. If there is no blocking diode or if the panel is damaged, electricity can flow back. In a DC-coupled Solar + Storage system, where a battery is installed in front of the inverter along with the PV, power can flow either directly to the grid through the inverter or to the battery where it can be stored and later discharged to the grid. How does a grid-tied solar system work? When. Insufficient Storage Capacity: Limited battery capacity can lead to energy overflow, causing your solar battery to discharge excess energy back to the grid. If the system is not tied to the grid, excess energy production would generally cause the charge controller to cease. A battery energy storage system (BESS) is an electrochemical device that charges (or collects energy) from the grid or a power plant and then discharges that energy at a later time to provide electricity or other grid services when needed. Several battery chemistries are available or under.