What is claimed is:1. A battery, comprising:a battery cell with an electrode terminal;a fire prevention pipeline configured to accommodate a fire prevention medium; anda fastener configured to fasten the fire prevention pipeline, wherein the fastener is connected to the electrode terminal and comprises:an accommodating hole that runs through the fastener; anda second convex portion comprising:a fixed portion connected to a wall of the accommodating hole; anda protruding portion connected to the fixed portion, a gap being present between the protruding portion and the wall of the accommodating hole, and the protruding portion protruding from a surface of the fastener facing the battery cell and elastically abutting against the battery cell.2. The battery according to claim 1, wherein the fastener further comprises an accommodating portion, the accommodating portion is configured to accommodate the electrode terminal, and the accommodating portion abuts against the electrode terminal to limit displacement of the fastener.3. The battery according to claim 2, wherein the accommodating portion has an opening, and at least part of the electrode terminal is exposed through the opening.4. The battery according to claim 2, wherein the accommodating portion is a through hole that runs through the fastener.5. The battery according to claim 2, wherein the fastener further comprises a first convex portion, the first convex portion is around the periphery of the accommodating portion, and the first convex portion protrudes in a direction away from the battery cell.6. The battery according to claim 1, wherein the second convex portion is configured to accommodate an assembly deviation between the fastener and the battery cell.7. The battery according to claim 1, wherein the second convex portion is elastic.8. The battery according to claim 1, wherein the protruding portion bends with respect to the fixed portion in a direction away from the battery cell when the protruding portion is subject to a force in the direction away from the battery cell.9. The battery according to claim 1, wherein the battery includes a plurality of second convex portions, and the plurality of second convex portions are arranged in positions that enable the fastener to receive a balanced force when the fastener abuts against the battery cell.10. The battery according to claim 1, wherein the battery cell further comprises a pressure relief mechanism, and the pressure relief mechanism is configured to be actuated to release the internal pressure when an internal pressure or a temperature of the battery cell reaches a threshold;the fire prevention pipeline is configured to discharge the fire prevention medium toward the battery cell when the pressure relief mechanism is actuated; andthe fastener is provided with a first weak zone, and the first weak zone is configured to allow the fire prevention medium to flow through the first weak zone to the battery cell when the pressure relief mechanism is actuated.11. The battery according to claim 10, wherein the first weak zone is a through hole; orthe first weak zone is configured to form a through hole when the pressure relief mechanism is actuated.12. The battery according to claim 10, wherein the fastener further comprises a buckle, the buckle is configured to fasten the fire prevention pipeline to the fastener, and the buckle is provided on two sides of the first weak zone along a central axis of the fire prevention pipeline.13. The battery according to claim 12, wherein the fastener further comprises a first depression, configured to accommodate at least part of the fire prevention pipeline, and the first weak zone and the buckle are both provided in the first depression.14. The battery according to claim 10, wherein the battery further comprises a separation part, configured for installing a busbar, the busbar is connected to the electrode terminal, and the fastener is located between the separation part and the battery cell to limit displacement of the fastener.15. The battery according to claim 14, wherein the separation part comprises a second weak zone, configured to allow emissions of the battery cell to pass through the second weak zone and destroy the fire prevention pipeline when the pressure relief mechanism is actuated.16. An electric apparatus, comprising the battery according to claim 1, wherein the battery is configured to supply electrical energy.17. A method for manufacturing batteries, comprising:installing a battery cell, wherein the battery cell has an electrode terminal;installing a fastener and connecting the fastener to the electrode terminal, wherein the fastener comprises:an accommodating hole that runs through the fastener; anda second convex portion comprising:a fixed portion connected to a wall of the accommodating hole; anda protruding portion connected to the fixed portion, a gap being present between the protruding portion and the wall of the accommodating hole, and the protruding portion protruding from a surface of the fastener facing the battery cell and elastically abutting against the battery cell; andinstalling a fire prevention pipeline and fastening the fire prevention pipeline to the fastener, wherein the fire prevention pipeline is configured to accommodate a fire prevention medium.18. A device for manufacturing batteries, comprising:a battery cell installation apparatus, configured to install a battery cell, wherein the battery cell has an electrode terminal;a fastener installation apparatus, configured to install a fastener and connect the fastener to the electrode terminal, wherein the fastener comprises:an accommodating hole that runs through the fastener; anda second convex portion comprising:a fixed portion connected to a wall of the accommodating hole; anda protruding portion connected to the fixed portion, a gap being present between the protruding portion and the wall of the accommodating hole, and the protruding portion protruding from a surface of the fastener facing the battery cell and elastically abutting against the battery cell; anda fire prevention pipeline installation apparatus, configured to install a fire prevention pipeline to the fastener, wherein the fire prevention pipeline is configured to accommodate a fire prevention medium.19. The battery according to claim 1, wherein the fastener further comprises:a main body; andtwo connecting portions located on opposite sides of the main body in a first direction;wherein a size of each of the two connecting portions in a second direction perpendicular to the first direction is smaller than a size of the main body in the second direction.