The invention relates to a battery redox flow system and a battery. The system comprises a connection pipeline, a liquid-cooling box, a liquid pump, a heat exchange device, a three-way device and a stop device, wherein a first port, a second port and a third port are arranged in the three-way device, the second port is connected with the liquid pump, the third port is connected with the liquid-cooling box, the liquid-cooling box is connected with a liquid inlet end of the heat exchange device by the liquid pump, a liquid outlet end of the heat exchange device is connected with the first port by a connection pipeline, the stop device is used for preventing a cooling liquid from flowing back, the stop device comprises a first stop piece, a second stop piece and a third stop piece, the firststop piece is arranged between the second port and the liquid pump, the second stop piece is arranged between the third port and the liquid-cooling box, and the third stop piece is arranged on the connection pipeline. By the system, the leaked cooling liquid can be recycled, the cooling liquid is prevented from being continuously leaked, the safety is improved, and energy is saved.