A battery, comprising: a battery cell, the battery cell comprising a pressure relief mechanism, the pressure relief mechanism being disposed on a first wall of the battery cell, and the pressure relief mechanism being configured to be actuated when an internal pressure or temperature of the battery cell reaches a threshold, to relieve the internal pressure; a thermal management component being configured to accommodate a fluid to adjust the temperature of the battery cell, and a first surface of the thermal management component being attached to the first wall; and a support, the support being arranged opposite to the pressure relief mechanism, the support being configured to support the pressure relief mechanism when the pressure relief mechanism is actuated, so that the pressure relief mechanism is opened at a predetermined angle, therefore emissions from the battery cell can be discharged toward the thermal management component; wherein the thermal management component is provided with a pressure relief hole, the pressure relief hole is arranged opposite to the pressure relief mechanism, and the pressure relief hole is configured to discharge the emissions; the thermal management component comprises a first thermally conductive plate and a second thermally conductive plate, the first thermally conductive plate is located between the first wall and the second thermally conductive plate and is attached to the first wall; a first region of the second thermally conductive plate is recessed away from the first thermally conductive plate to form a groove, a flow channel is formed in the groove, the flow channel is configured to accommodate the fluid, the pressure relief hole is disposed on a second region of the thermal management component, and the second region is not a region corresponding to the flow channel; the support is disposed in the thermal management component, or, the support is disposed between the thermal management component and the battery cell; a structure of the support is a hollow structure, the support accommodates a fluid, the support is configured to be damaged by the emissions when the pressure relief mechanism is actuated, so that the fluid in the support is discharged, thereby reducing the temperature of the emissions from the battery cell. a battery cell, the battery cell comprising a pressure relief mechanism, the pressure relief mechanism being disposed on a first wall of the battery cell, and the pressure relief mechanism being configured to be actuated when an internal pressure or temperature of the battery cell reaches a threshold, to relieve the internal pressure; a thermal management component being configured to accommodate a fluid to adjust the temperature of the battery cell, and a first surface of the thermal management component being attached to the first wall; and a support, the support being arranged opposite to the pressure relief mechanism, the support being configured to support the pressure relief mechanism when the pressure relief mechanism is actuated, so that the pressure relief mechanism is opened at a predetermined angle, therefore emissions from the battery cell can be discharged toward the thermal management component; wherein the thermal management component is provided with a pressure relief hole, the pressure relief hole is arranged opposite to the pressure relief mechanism, and the pressure relief hole is configured to discharge the emissions; the thermal management component comprises a first thermally conductive plate and a second thermally conductive plate, the first thermally conductive plate is located between the first wall and the second thermally conductive plate and is attached to the first wall; a first region of the second thermally conductive plate is recessed away from the first thermally conductive plate to form a groove, a flow channel is formed in the groove, the flow channel is configured to accommodate the fluid, the pressure relief hole is disposed on a second region of the thermal management component, and the second region is not a region corresponding to the flow channel; the support is disposed in the thermal management component, or, the support is disposed between the thermal management component and the battery cell; a structure of the support is a hollow structure, the support accommodates a fluid, the support is configured to be damaged by the emissions when the pressure relief mechanism is actuated, so that the fluid in the support is discharged, thereby reducing the temperature of the emissions from the battery cell.