A short circuit protection device for lithium battery pack

Abstract

The utility model relates to the field of lithium battery pack short circuit protection, specifically is a kind of lithium battery pack short circuit fast protection device, including shell, the inner wall of shell is fixedly connected with first baffle, the inner wall of shell is slidably inserted with second baffle, the side of second baffle is provided with cutting mechanism;The utility model can drive transmission rod reciprocating swing while transmission plate rotates, transmission rod is movably connected between transmission plate and sliding seat by first connecting rod and second connecting rod, transmission rod reciprocating swing can push sliding seat along slide rail reciprocating sliding, cutting knife is fixedly connected with reciprocating sliding seat by connecting plate, cutting knife and anti-damage plate adhere to lithium battery pack main body's connecting line can be cut off, and reciprocating cutting action is carried out under the cooperation of transmission plate and transmission rod, to cut off connecting line quickly can interrupt current path, avoid heat to continue to accumulate and cause battery thermal runaway, reduce fire, explosion risk.

Description

Technical Field

[0001] This utility model relates to the field of short-circuit protection for lithium battery packs, specifically a fast short-circuit protection device for lithium battery packs. Background Technology

[0002] A lithium battery pack is a battery system composed of multiple lithium battery cells connected in series and parallel. It is widely used in modern energy storage and power systems. The working principle of a lithium battery pack is based on the process of lithium ions being inserted and extracted between the positive and negative electrodes. During charging, lithium ions are extracted from the positive electrode and inserted into the negative electrode through the electrolyte, leaving the negative electrode in a lithium-rich state. During discharging, the opposite occurs: lithium ions are extracted from the negative electrode and return to the positive electrode through the electrolyte, while electrons form a current through the external circuit to power the load.

[0003] Short circuits in lithium-ion battery packs are a critical safety issue, potentially caused by external or internal factors, and can lead to serious consequences such as thermal runaway, fire, or even explosion. However, most traditional short-circuit protection devices for lithium-ion battery packs cannot quickly disconnect the battery connection wires. The instantaneous short-circuit current can reach tens or even hundreds of times the rated current, generating a large amount of heat. If the connection wires cannot be quickly disconnected, the continuous accumulation of heat will cause the battery temperature to rise sharply, potentially triggering reactions such as separator melting and electrolyte vaporization, which in turn can trigger battery thermal runaway. Furthermore, the continuous short-circuit current can severely damage the internal structure of the battery, such as electrode material shedding and electrolyte decomposition, leading to a decrease in battery capacity, an increase in internal resistance, or even complete failure. Utility Model Content

[0004] To overcome the shortcomings of existing technologies, most traditional short-circuit fast protection devices for lithium battery packs cannot quickly disconnect the lithium battery connection wires. The instantaneous current during a short circuit can reach tens or even hundreds of times the rated current, generating a large amount of heat. If the connection wires cannot be quickly disconnected, the continuous accumulation of heat will lead to problems such as a sharp rise in battery temperature. This utility model proposes a short-circuit fast protection device for lithium battery packs.

[0005] The technical solution adopted by this utility model to solve its technical problem is: a short-circuit fast protection device for lithium battery pack, including a shell, a first partition plate fixedly connected to the inner wall of the shell, a top cover fixedly connected to the top of the shell, a second partition plate slidably inserted into the inner wall of the shell, and a cutting mechanism provided on one side of the second partition plate.

[0006] The cutting mechanism includes a slide rail, one side of which is fixedly connected to one side of a second partition. A sliding seat is slidably connected to the surface of the slide rail. A connecting plate is fixedly connected to one side of the sliding seat. A cutter is fixedly connected to one side of the connecting plate. A support plate is fixedly connected to one side of the second partition. A damage prevention plate is fixedly connected to one side of the support plate.

[0007] Preferably, a wire-passing groove is provided on one side of the second partition, an isolation block is inserted into the inner wall of the wire-passing groove, and a first wire-passing hole is provided on one side of the isolation block.

[0008] Preferably, a motor is fixedly installed on one side of the second partition, a transmission plate is fixedly connected to the output end of the motor, a first connecting rod is fixedly connected to one side of the transmission plate, and a transmission rod is rotatably connected to the surface of the first connecting rod.

[0009] Preferably, a second connecting rod is fixedly connected to one side of the sliding seat, and the other end of the transmission rod is rotatably connected to the surface of the second connecting rod.

[0010] Preferably, an explosion-proof plate is inserted into the inner wall of the outer casing, and a lithium battery pack body is inserted into the inner wall of the explosion-proof plate. A second wire hole is provided on one side of the explosion-proof plate, and the inner wall of the second wire hole is connected to the inner wall of the first wire hole.

[0011] Preferably, a liquid storage box is fixedly connected to the inner wall of the outer shell, a water pump is fixedly installed on one side of the liquid storage box, the output end of the water pump is fixedly connected to a liquid supply pipe, and a return pipe is fixedly connected to one side of the liquid storage box.

[0012] Preferably, the explosion-proof plate has a flow channel in its inner cavity, and there are multiple flow channels. An inlet pipe and an outlet pipe are fixedly connected to one side of the explosion-proof plate. The inner walls of the inlet pipe and the outlet pipe are connected to the inner walls of the flow channels. One end of the inlet pipe is fixedly connected to one end of the supply pipe, and one end of the outlet pipe is fixedly connected to one end of the return pipe.

[0013] The advantages of this utility model are:

[0014] This invention utilizes a motor to drive a transmission plate to rotate. Simultaneously, the rotation of the transmission plate causes a transmission rod to reciprocate. The transmission rod is movably connected between the transmission plate and the sliding seat via a first and second connecting rod. The reciprocating motion of the transmission rod pushes the sliding seat to slide along a slide rail. A cutter is fixedly connected to the reciprocating sliding seat via a connecting plate. When the cutter contacts the anti-damage plate, it cuts the connecting wires of the lithium battery pack. The reciprocating cutting action, performed in conjunction with the transmission plate and transmission rod, minimizes the error rate of single-cutting operations, thus quickly cutting off the connecting wires and interrupting the current path. This prevents the continuous accumulation of heat from causing battery thermal runaway, reducing the risk of fire and explosion. It solves the problem that most traditional lithium battery pack short-circuit fast protection devices cannot quickly cut off the lithium battery connecting wires. Short-circuit currents can reach tens or even hundreds of times the rated current, generating a large amount of heat. If the connecting wires cannot be cut off quickly, the continuous accumulation of heat can lead to a rapid rise in battery temperature. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a three-dimensional schematic diagram of the overall device of this utility model;

[0017] Figure 2 This is a three-dimensional schematic diagram of the internal structure of the outer shell of this utility model;

[0018] Figure 3 This is a three-dimensional schematic diagram of the cutting mechanism of this utility model;

[0019] Figure 4 This is a schematic diagram showing the connection between the explosion-proof plate and the liquid storage box of this utility model.

[0020] In the diagram: 1. Outer shell; 2. First partition; 3. Top cover; 4. Second partition; 5. Cutting mechanism; 501. Slide rail; 502. Sliding seat; 503. Connecting plate; 504. Cutter; 505. Support plate; 506. Damage protection plate; 6. Wire channel; 7. Isolation block; 8. First wire hole; 9. Motor; 10. Transmission plate; 11. First connecting rod; 12. Transmission rod; 13. Second connecting rod; 14. Explosion-proof plate; 15. Lithium battery pack body; 16. Second wire hole; 17. Liquid storage box; 18. Water pump; 19. Liquid supply pipe; 20. Liquid return pipe; 21. Flow channel; 22. Liquid inlet pipe; 23. Liquid outlet pipe. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0022] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0023] This application discloses a fast short-circuit protection device for lithium battery packs. (Refer to...) Figures 1 to 3A short-circuit fast protection device for a lithium battery pack includes a housing 1, a first partition 2 fixedly connected to the inner wall of the housing 1, a top cover 3 fixedly connected to the top of the housing 1, an explosion-proof plate 14 inserted into the inner wall of the housing 1, a lithium battery pack body 15 inserted into the inner wall of the explosion-proof plate 14, a second wire hole 16 opened on one side of the explosion-proof plate 14, a second partition 4 slidably inserted into the inner wall of the housing 1, and a cutting mechanism 5 provided on one side of the second partition 4.

[0024] The cutting mechanism 5 includes a slide rail 501, one side of which is fixedly connected to one side of the second partition 4. A sliding seat 502 is slidably connected to the surface of the slide rail 501. A connecting plate 503 is fixedly connected to one side of the sliding seat 502. A cutter 504 is fixedly connected to one side of the connecting plate 503. A support plate 505 is fixedly connected to one side of the second partition 4. A damage prevention plate 506 is fixedly connected to one side of the support plate 505. A motor 9 is fixedly installed on one side of the second partition 4. A transmission plate 10 is fixedly connected to the output end of the motor 9. A first connecting rod 11 is fixedly connected to one side, and a transmission rod 12 is rotatably connected to the surface of the first connecting rod 11. A second connecting rod 13 is fixedly connected to one side of the sliding seat 502, and the other end of the transmission rod 12 is rotatably connected to the surface of the second connecting rod 13. In this lithium battery pack short-circuit fast protection device, the outer shell 1 and the top cover 3 play the main role of installation and protection. The first partition 2 can separate the inner cavity of the outer shell 1 to ensure reasonable installation between structures. The second partition 4 mainly supports the cutting mechanism 5. The second partition 4 is detachable and can be fixedly connected to the outer shell 1 by bolts. The outer shell 1 can be equipped with a Hall current sensor (not shown in the figure) to monitor the current in real time. When the current rise rate exceeds the threshold, the signal is received by the control system (such as PLC) and the signal is processed to activate the motor 9. The operation of the motor 9 can drive the transmission plate 10 to rotate. While the transmission plate 10 rotates, it can drive the transmission rod 12 to swing back and forth. The transmission rod 12 is movably connected between the transmission plate 10 and the sliding seat 502 through the first connecting rod 11 and the second connecting rod 13. While the lever 12 swings back and forth, it can push the sliding seat 502 to slide back and forth along the slide rail 501. The cutter 504 is fixedly connected to the reciprocating sliding seat 502 through the connecting plate 503. When the cutter 504 is in contact with the anti-damage plate 506, it can cut the connecting wire of the lithium battery pack body 15. With the cooperation of the transmission plate 10 and the transmission lever 12, the reciprocating cutting action is performed to minimize the error rate of single cutting. In this way, the connection wire can be quickly cut off to interrupt the current path, avoid the continuous accumulation of heat and cause battery thermal runaway, and reduce the risk of fire and explosion.

[0025] In addition, the explosion-proof plate 14 can be made of metal composite material to increase the robustness of the outer shell 1 and minimize the occurrence of short circuits in the lithium battery pack body 15.

[0026] Reference Figure 3A wire-passing groove 6 is provided on one side of the second partition 4. An insulating block 7 is inserted into the inner wall of the wire-passing groove 6. A first wire-passing hole 8 is provided on one side of the insulating block 7. The inner wall of the second wire-passing hole 16 is connected to the inner wall of the first wire-passing hole 8. Through the insulating block 7, the wire-passing groove 6 facilitates the connection of the connecting wires on the lithium battery pack body 15. The insulating block 7 can be made of rubber to seal the wire-passing groove 6, so as to avoid excessive contact between the lithium battery pack body 15 and air when it catches fire. The connecting wires of the lithium battery pack body 15 can be connected to the external power supply equipment through the second wire-passing hole 16 and the first wire-passing hole 8.

[0027] Reference Figure 2 and Figure 4 A liquid storage box 17 is fixedly connected to the inner wall of the outer shell 1. A water pump 18 is fixedly installed on one side of the liquid storage box 17. The output end of the water pump 18 is fixedly connected to a liquid supply pipe 19. A return pipe 20 is fixedly connected to one side of the liquid storage box 17. A flow channel 21 is opened in the inner cavity of the explosion-proof plate 14. There are multiple flow channels 21. An inlet pipe 22 and an outlet pipe 23 are fixedly connected to one side of the explosion-proof plate 14. The inner walls of the inlet pipe 22 and the outlet pipe 23 are connected to the inner wall of the flow channel 21. One end of the inlet pipe 22 is connected to the liquid supply pipe 19. One end of the outlet pipe 23 is fixedly connected to the other end of the return pipe 20. The storage box 17 can store coolant for cooling. When the lithium battery pack body 15 is short-circuited, the coolant can be drawn by the water pump 18. The coolant enters the inner cavity flow channel 21 of the explosion-proof plate 14 through the supply pipe 19 and the inlet pipe 22. The coolant circulates through the outlet pipe 23 and the return pipe 20 to cool the explosion-proof plate 14, thereby further improving the protection effect on the lithium battery pack body 15.

[0028] Working principle: The outer shell 1 and top cover 3 serve as the main installation and protection components. The first partition 2 divides the inner cavity of the outer shell 1, ensuring proper installation between structures. The second partition 4 provides main support for the cutting mechanism 5. The second partition 4 is detachable and can be fixed to the outer shell 1 with bolts. The outer shell 1 can be equipped with existing technology Hall current sensors to monitor the current in real time. When the current rise rate exceeds a threshold, the existing technology control system receives and processes the signal to activate the motor 9. At the same time, the water pump 18 draws coolant. The operation of the motor 9 drives the transmission plate 10 to rotate. The rotation of the transmission plate 10 drives the transmission rod 12 to swing back and forth. The transmission rod 12 is movably connected to the transmission plate 10 and the sliding seat 502 through the first connecting rod 11 and the second connecting rod 13. During this process, the transmission rod 12 swings back and forth, pushing the sliding seat 502 to slide back and forth along the slide rail 501. The cutter 504 is fixedly connected to the reciprocating sliding seat 502 through the connecting plate 503. When the cutter 504 is in contact with the anti-damage plate 506, it can cut the connecting wire of the lithium battery pack body 15. With the cooperation of the transmission plate 10 and the transmission rod 12, the reciprocating cutting action is performed to minimize the error rate of single cutting. The coolant enters the inner cavity flow channel 21 of the explosion-proof plate 14 through the supply pipe 19 and the inlet pipe 22. The coolant circulates through the outlet pipe 23 and the return pipe 20 to cool the explosion-proof plate 14, further improving the protection effect on the lithium battery pack body 15. The quick cutting of the connecting wire can interrupt the current path, avoid the continuous accumulation of heat and cause battery thermal runaway, and reduce the risk of fire and explosion.

[0029] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A short-circuit fast protection device for a lithium battery pack, comprising a housing (1), characterized in that: The inner wall of the outer shell (1) is fixedly connected to a first partition (2), the top of the outer shell (1) is fixedly connected to a top cover (3), the inner wall of the outer shell (1) is slidably inserted with a second partition (4), and a cutting mechanism (5) is provided on one side of the second partition (4). The cutting mechanism (5) includes a slide rail (501), one side of which is fixedly connected to one side of the second partition (4). A sliding seat (502) is slidably connected to the surface of the slide rail (501). A connecting plate (503) is fixedly connected to one side of the sliding seat (502). A cutter (504) is fixedly connected to one side of the connecting plate (503). A support plate (505) is fixedly connected to one side of the second partition (4). A damage prevention plate (506) is fixedly connected to one side of the support plate (505).

2. The lithium battery pack short-circuit fast protection device according to claim 1, characterized in that: The second partition (4) has a wire groove (6) on one side, and an isolation block (7) is inserted into the inner wall of the wire groove (6). The isolation block (7) has a first wire hole (8) on one side.

3. The lithium battery pack short-circuit fast protection device according to claim 1, characterized in that: A motor (9) is fixedly installed on one side of the second partition (4). A transmission plate (10) is fixedly connected to the output end of the motor (9). A first connecting rod (11) is fixedly connected to one side of the transmission plate (10). A transmission rod (12) is rotatably connected to the surface of the first connecting rod (11).

4. A lithium battery pack short-circuit fast protection device according to claim 3, characterized in that: A second connecting rod (13) is fixedly connected to one side of the sliding seat (502), and the other end of the transmission rod (12) is rotatably connected to the surface of the second connecting rod (13).

5. A lithium battery pack short-circuit fast protection device according to claim 1, characterized in that: An explosion-proof plate (14) is inserted into the inner wall of the outer shell (1), and a lithium battery pack body (15) is inserted into the inner wall of the explosion-proof plate (14). A second wire hole (16) is opened on one side of the explosion-proof plate (14), and the inner wall of the second wire hole (16) is connected to the inner wall of the first wire hole (8).

6. A lithium battery pack short-circuit fast protection device according to claim 1, characterized in that: A liquid storage box (17) is fixedly connected to the inner wall of the outer shell (1). A water pump (18) is fixedly installed on one side of the liquid storage box (17). The output end of the water pump (18) is fixedly connected to a liquid supply pipe (19). A return pipe (20) is fixedly connected to one side of the liquid storage box (17).

7. A lithium battery pack short-circuit fast protection device according to claim 5, characterized in that: The explosion-proof plate (14) has a flow channel (21) in its inner cavity. There are multiple flow channels (21). An inlet pipe (22) and an outlet pipe (23) are fixedly connected to one side of the explosion-proof plate (14). The inner walls of the inlet pipe (22) and the outlet pipe (23) are connected to the inner wall of the flow channel (21). One end of the inlet pipe (22) is fixedly connected to one end of the supply pipe (19), and one end of the outlet pipe (23) is fixedly connected to one end of the return pipe (20).

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