Lithium battery thermal runaway detection device

Abstract

The invention discloses a lithium battery thermal runaway detection device, and relates to the field of battery thermal runaway detection. A gas flowing gap is formed between the battery body and the shell, a first shunting part is arranged in the shell, the first shunting part can move into or out of the gap, the gap is divided into a plurality of first channels in a first direction when the first shunting part moves into the gap, at least one detection device is arranged on one side of the shell, and the detection device is arranged on the other side of the shell. The first shunting piece is used for detecting thermal runaway data of the gap or the first channel and is connected with a first driving mechanism for driving the first shunting piece to move; according to the lithium battery thermal runaway detection device, through the arrangement of the first flow dividing piece, in the early stage of battery thermal runaway, escaped gas is restrained at the first channel where the first flow dividing piece belongs, the diffusible space of the gas is reduced, the gas concentration reduction degree is reduced, and the detection device can detect gas data information in the early stage of thermal runaway in time.

Description

Technical Field

[0001] The present invention relates to a lithium battery thermal runaway detection technology, and in particular to a lithium battery thermal runaway detection device. Background Art

[0002] When a battery experiences thermal runaway, temperature rise and gas escape will occur. In order to improve safety and avoid a series of problems caused by thermal runaway, an external detection device is usually set up to monitor the thermal runaway of the battery pack. The main means are to detect temperature, gas composition, etc. Although thermal runaway can be accurately judged by temperature monitoring, when thermal runaway occurs, gas escape usually occurs in the early stage, and temperature rise is shown later. At this time, it is generally in the middle stage of thermal runaway. Although the detection device can also monitor by detecting gas, due to the small amount of gas escape in the early stage, when thermal runaway occurs in the battery cell at a local position, the escaped gas diffuses in the space inside the battery pack or the space where the battery pack is located, which reduces the detectable gas concentration, affects the timely detection of the detection device, and has a certain hysteresis, making it difficult to perform timely and accurate detection in the early stage of thermal runaway. Summary of the invention

[0003] The purpose of the present invention is to provide a lithium battery thermal runaway detection device to solve the above-mentioned deficiencies in the prior art.

[0004] In order to achieve the above-mentioned purpose, the present invention provides the following technical solutions: a lithium battery thermal runaway detection device, comprising a battery body and a shell; a gap for gas flow is provided between the battery body and the shell, a first diverter is arranged in the shell, the first diverter can move into or out of the gap, and when the first diverter moves into the gap, the gap is divided into a plurality of first channels in a first direction, at least one detection device is provided on one side of the shell, for detecting thermal runaway data of the gap or the first channel, and the first diverter is connected to a first driving mechanism for driving its movement.

[0005] Furthermore, a second flow divider is arranged in the housing, and the second flow divider can move into or out of the gap, and when the second flow divider moves into the gap, the gap is divided into a plurality of second channels in the second direction.

[0006] Furthermore, the detection devices are respectively arranged on one side of each first channel and each second channel.

[0007] Furthermore, a detection device is respectively provided on one side of the first channel and the second channel.

[0008] Furthermore, the detection device is connected with each first channel and / or each second channel in sequence through an alternating connecting device.

[0009] Furthermore, the alternating connection device includes a box body, a cavity for accommodating the detection device is opened in the box body, and a diversion channel connecting the cavity and each first channel respectively is opened in the box body, and a switch component for closing or opening the diversion channel is arranged in the box body.

[0010] Furthermore, the cavity is circular, and the outlet of the guide channel is located on the peripheral side of the cavity. The switching component includes an arc-shaped door plate, which abuts against the peripheral side of the cavity and can rotate around the axis of the cavity. When the arc-shaped door plate moves to the outlet position of the guide channel, the guide channel is closed. The arc-shaped door plate is connected to a rotating part for driving its rotation.

[0011] Furthermore, the rotating part includes a rotating ring located in the cavity and rotatably connected to the inner wall of the box body, a tooth portion is provided on the inner side of the rotating ring, the tooth portion is meshed with a first gear, the first gear is rotatably connected to the box body, and one side of the first gear is fixedly connected to one end of the output shaft of the motor.

[0012] Furthermore, the second flow dividing member is connected to a second driving mechanism for driving the movement of the second flow dividing member.

[0013] A method for detecting thermal runaway of a lithium battery, applicable to the thermal runaway detection device of a lithium battery as described above, specifically comprises the following steps:

[0014] S101, moving the first flow dividing member to form a first channel, detecting each first channel, and obtaining detection data corresponding to each first channel;

[0015] S102, moving the second flow dividing member to form a second channel, detecting each second channel, and obtaining detection data corresponding to each second channel;

[0016] S103. Locate the thermal runaway area.

[0017] Compared with the prior art, the lithium battery thermal runaway detection device provided by the present invention has the following beneficial effects:

[0018] The lithium battery thermal runaway detection, through the provision of a first shunt member, can confine the escaping gas to the first channel to which it belongs in the early stage before the battery thermal runaway, thereby reducing the space in which the gas can diffuse and the degree of reduction in gas concentration, so that the detection device can timely detect the gas data information in the early stage of thermal runaway. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0020] Figure 1 A partial cross-sectional view of a detection device provided by an embodiment of the present invention installed on a housing;

[0021] Figure 2 The embodiment of the present invention provides Figure 1 Schematic diagram of the structure after the cavity in is opened;

[0022] Figure 3 The embodiment of the present invention provides Figure 2 The enlarged view of point A in the middle;

[0023] Figure 4 The embodiment of the present invention provides Figure 1 Schematic diagram of local longitudinal section structure;

[0024] Figure 5 A partial cross-sectional view of a housing provided by an embodiment of the present invention;

[0025] Figure 6 The embodiment of the present invention provides Figure 5 A schematic diagram of the connection state of the first driving member and the second driving member with the first flow dividing member and the second flow dividing member;

[0026] Figure 7 A schematic diagram of the driving state of the first driving member and the second driving member at the same time provided by an embodiment of the present invention;

[0027] Figure 8 A schematic diagram of a first driving member and a second driving member driving at the same time after a delay member is installed according to an embodiment of the present invention;

[0028] Fig. 9 A schematic diagram of the thermal runaway region positioning state provided in an embodiment of the present invention.

[0029] Description of reference numerals:

[0030] 1. Battery body; 2. Shell; 3. Gap; 4. First diverter; 41. First channel; 42. First partition; 43. First drive; 431. Threaded rod; 432. Threaded sleeve; 433. Push-pull rod; 5. Second diverter; 51. Second partition; 52. Second drive; 521. Bevel gear assembly; 522. Sliding cylinder; 523. Moving seat; 6. Detection device; 7. Alternating connection device; 71. Box body; 72. Cavity; 73. Guide channel; 74. Switch component; 741. Arc door panel; 742. Swivel; 743. Tooth; 744. First gear; 745. Motor; 8. Avoidance groove. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0032] For examples, see Figure 1 - Figure 8 A lithium battery thermal runaway detection device comprises a battery body 1 and a shell 2, wherein a gap 3 for gas flow is provided between the battery body 1 and the shell 2, a first diverter 4 is arranged in the shell 2, the first diverter 4 can move into or out of the gap 3, and when the first diverter 4 moves into the gap 3, the gap 3 is divided into a plurality of first channels 41 in a first direction, at least one detection device 6 is arranged on one side of the shell 2, for detecting thermal runaway data of the gap 3 or the first channel 41, and the first diverter 4 is connected to a first driving mechanism for driving the movement thereof.

[0033] In one embodiment of the present invention, the first flow divider 4 is composed of a plurality of first baffles 42 arranged in parallel, and the length direction of the first baffles 42 is perpendicular to the first direction. It should be understood that the first direction is the length direction or width direction of the housing 2. Here, the first direction is taken as Figure 1 The width direction of the housing 2 is shown as an example. After the first flow divider 4 moves to the gap 3, the gap 3 is divided into a plurality of parallel first channels 41;

[0034] It should be noted that after the first flow divider 4 moves to the gap 3, the first channel 41 is formed by one side of the battery body 1 and the inner side of the housing 2, and the outlet of the first channel 41 is connected to the detection device 6. The gas generated during thermal runaway will enter the detection device 6 along the first channel 41 for detection;

[0035] The formation of the first channel 41 separates the gap 3 between the battery body 1 and the shell 2. When the first channel 41 detects corresponding data, it means that the first channel 41 has a corresponding event. For example, if the gas component in the early stage of thermal runaway is detected, it means that the battery body 1 has a thermal runaway phenomenon at the first channel 41. At this time, the inhibitor can be transported into the first channel 41 to suppress it. Specifically, a fire extinguishing device (not shown in the figure) is connected to the shell 2. An example of a fire extinguishing device is provided, which includes a nozzle, a partition control valve and a pipeline. The pipeline is connected to an automatic fire extinguishing device, such as a perfluorohexanone fire extinguishing device, etc. The implementation method is a prior art and will not be described in detail here.

[0036] By setting the first shunt member 4, in the initial stage before the thermal runaway of the battery, the escaped gas is confined to the first channel 41 to which it belongs, reducing the space where it can diffuse and the degree of reduction in gas concentration, so that the detection device 6 can detect the data information of the gas in time. At the same time, the formation of the first channel 41 will also obtain the relative position of the battery where the thermal runaway occurs, which is conducive to positioning the inhibitor to a more accurate thermal runaway area when delivering it;

[0037] In one embodiment of the present invention, generally, each first channel 41 may be provided with a corresponding detection device 6, which is used to detect and obtain data information of each first channel 41, but generally, the volume of a battery pack formed by combining multiple battery bodies 1 is limited. When used in some energy storage solutions, the setting of multiple detection devices 6 will occupy more of their own space and overall space. Therefore, a method of using fewer detection devices 6 to detect multiple first channels 41 is designed, that is, one detection device 6 can correspond to multiple first channels 41;

[0038] Specifically, an alternating communication device 7 is provided on one side of the first channel 41, which is used to communicate with each first channel 41 in sequence. The alternating communication device 7 includes a box body 71, which is fixedly connected to one side of the housing 2. The box body 71 is provided with a cavity 72 for accommodating the detection device 6, and a guide channel 73 respectively connecting the cavity 72 and each first channel 41. The box body 71 is provided with a switch component 74 for closing or opening the guide channel 73;

[0039] In one embodiment of the present invention, a specific example of a switch component 74 is provided. The switch component 74 is a general plate-shaped valve, which is independently arranged in each diversion channel 73. The plate-shaped valve is moved into or out of the diversion channel 73 to achieve closure or opening. The plate-shaped valve is moved by a cylinder or an electric telescopic rod, and the above-mentioned method is a prior art, so it is not specifically described in this technical solution, and is not drawn in the drawings. Based on the technical field, it will not cause trouble to this technical solution. By controlling the diversion channel 73 to be opened or closed, different first channels 41 are connected to the detection device 6 for detection;

[0040] It should be understood that when using one detection device 6 to detect multiple first channels 41, the switch component 74 for switching different first channels 41 to connect with the detection device 6 has a certain switching frequency. Generally speaking, it connects each first channel 41 in sequence at a certain time interval.

[0041] In one embodiment of the present invention, another specific example of a switch component 74 is provided, which has the advantages of convenient switching and fewer structures compared with the above-mentioned plate-shaped valve method;

[0042] like Figure 2 and Figure 3 As shown, specifically:

[0043] The cavity 72 is circular, and the outlet of the guide channel 73 is located at the periphery of the cavity 72. The switch component 74 includes an arc-shaped door plate 741, which abuts against the periphery of the cavity 72 and can rotate around the axis of the cavity 72. When the arc-shaped door plate 741 moves to the outlet position of the guide channel 73, the guide channel 73 is closed. The arc-shaped door plate 741 is connected to a rotating member for driving the rotation thereof.

[0044] In one embodiment of the present invention, the rotating member includes a swivel 742 located in the cavity 72 and rotatably connected to the inner wall of the box body 71. A tooth portion 743 is provided on the inner side of the swivel 742. The tooth portion 743 is meshingly connected to a first gear 744. The first gear 744 is rotatably connected to the box body 71, and one side of the first gear 744 is fixedly connected to one end of the output shaft of the motor 745. The first gear 744 is driven to rotate by the motor 745 to drive the swivel 742 to rotate. One side of the swivel 742 is connected to the arc door panel 741, thereby driving the arc door panel 741 to rotate so that it can rotate to the outlet of each guide channel 73.

[0045] In one embodiment of the present invention, a specific example of a first driving member 43 is provided. The first driving member 43 includes a plurality of cylinders. The cylinder bodies of the cylinders are fixedly mounted on one side of the outer shell 2. The piston rods of the cylinders are connected to one end of the first partition 42. It should be understood that cylinders are provided at both ends of the same first partition 42, and the cylinders extend and retract synchronously, thereby driving the movement of the first partitions 42.

[0046] In one embodiment of the present invention, another specific example of the first driving member 43 is provided, which includes two threaded rods 431, the threaded rods 431 are located at both ends of the first partition 42 and are rotatably connected to the inner wall of the shell 2, and threaded sleeves 432 corresponding to the number of the first partitions 42 are threadedly connected to the threaded rods 431, and the side wall of the threaded sleeves 432 is rotatably connected to the push-pull rod 433, and the other end of the push-pull rod 433 is rotatably connected to one end of the first partition 42. It should be noted that when the threaded sleeve 432 moves to the end of the stroke away from the side corresponding to the first partition 42, the push-pull rod 433 is inclined, that is, it has a certain angle, so that the threaded sleeve 432 can push the first partition 42 to move when it approaches the first partition 42, and the two threaded rods 431 rotate synchronously, which can be connected by a synchronous belt drive, or stepper motors are respectively connected to one end of the two threaded rods 431, and the two threaded rods 431 are driven to rotate synchronously by the stepper motor;

[0047] In one embodiment of the present invention, a second flow divider 5 may be further provided. The second flow divider 5 can be moved into or out of the gap 3, and when the second flow divider 5 moves into the gap 3, the gap 3 is divided into a plurality of second channels in a second direction; wherein the second direction is perpendicular to the first direction, that is, the second direction is the length direction of the housing 2 at this time, and the second flow divider 5 is also composed of a plurality of second partitions 51 arranged in parallel; after the second flow divider 5 moves to the gap 3, the gap 3 is divided into a plurality of parallel second channels;

[0048] In one embodiment of the present invention, in the same configuration, a detection device 6 is also provided on one side of each second channel. One detection device 6 may be provided on one side of each second channel or one detection device 6 may be provided on one side of each second channel. The method is the same as the method of providing the detection device 6 at the first channel 41 described above, and will not be described in detail herein.

[0049] In one embodiment of the present invention, only one detection device 6 may be provided corresponding to each first channel 41 and the second channel. Specifically, the arrangement of each first channel 41 remains unchanged, that is, each flow guiding channel 73 is connected to the cavity 72, and each second channel needs to be connected to the cavity 72 through the extended flow guiding channel 73. That is to say, the box body 71 of the alternating communication device 7 also needs to extend a portion to the other side of the shell 2, so as to dock and communicate with the outlet of each second channel, which is not shown in the figure. At this time, the cavity 72 is used to detect the corresponding data of each first channel 41 and the second channel at the same time. It should be noted that only one detection device 6 is provided, which will increase the number of first channels 41 and second channels, resulting in a longer time interval for a cycle detection, affecting the timeliness of the detection. Therefore, this method is suitable for the case where the number of first channels 41 and second channels is small, or it is suitable for the case where the number of battery cells in the battery pack is small. It should be understood that the battery cell can be a battery pack composed of multiple batteries. When the number of first channels 41 and second channels required is large, a detection device 6 can be used to correspond to a small number of first channels 41 or second channels, so as to complete a cycle detection within a certain time interval.

[0050] By setting up the second channel to separate the gap 3 in the second direction, the detection device 6 can further locate the position of the thermal runaway. Specifically, taking the detection of escaping gas as an example, when the thermal runaway phenomenon is detected at a first channel 41, the first diverter 4 is moved out of the gap 3, and the second diverter 5 is moved into the gap 3 to form each second channel. By detecting the gas escape situation of the second channel, the second channel position where the thermal runaway position is located is obtained. By comparing the positions of the first channel 41 and the second channel, the relative position of the thermal runaway can be obtained, such as Fig. 9As shown, X represents the first channel 41 and Y represents the second channel. It shows an example of locating the thermal runaway position after detecting the first channel 41 and the second channel at one time during thermal runaway (the position shown by × in the figure). It should be noted that even if multiple thermal runaways occur, this method can still locate the thermal runaway position more accurately.

[0051] In one embodiment of the present invention, an example of a second driving member 52 is provided, which is arranged in the same manner as the first driving member 43, that is, driven by a plurality of cylinders, and will not be described in detail herein.

[0052] In one embodiment of the present invention, another second driving member 52 is provided, which is also driven by the threaded rod 431 to drive the second diverter member 5, which will not be described in detail here.

[0053] In one embodiment of the present invention, a method for linking the first driving member 43 and the second driving member 52 is also provided, such as Figure 5 and Figure 6 As shown, the threaded rod 431 of the first driving member 43 is connected to the threaded rod 431 of the second driving member 52 through a bevel gear assembly 521. Specifically, one end of the threaded rod 431 of the first driving member 43 and the second driving member 52 is fixedly connected to a bevel gear, and the bevel gears at the ends of two adjacent threaded rods 431 are meshed.

[0054] It should be noted that, only through the setting of the threaded sleeve 432 and the push-pull rod 433, when the first driving member 43 is linked with the second driving member 52, the first diverter member 4 or the second diverter member 5 is required to be initially located in the gap 3, and when detecting, the first diverter member 4 and the second diverter member 5 are alternately moved into or out of the gap 3, that is, before and after the detection by the detection device 6, the first diverter member 4 or the second diverter member 5 is always present in the gap 3, although the thickness of the first partition plate 42 and the second partition plate 51 can be set thin enough so as not to affect the normal use of the battery pack and the detection device 6, but for some gaps 3 with certain usage requirements (such as heat dissipation, input of inhibitors during thermal runaway, etc.), the first diverter member 4 is often required before and after the detection. and the second diverter member 5 are both moved out of the gap 3. For this purpose, on the basis of the above, a modified embodiment is further provided. Specifically, a delay component is installed on the threaded rod 431 of the first driving member 43 or the second driving member 52, which includes a sliding cylinder 522. The inner wall of the sliding cylinder 522 is threadedly connected to the surface of the threaded rod 431. The surface of the sliding sleeve is slidably connected with a moving seat 523. The moving seat 523 is rotatably connected to the end of the push-pull rod 433. In this way, the rotation of the threaded rod 431 will first push the sliding cylinder 522 to rotate. When one end of the sliding cylinder 522 abuts against the end of the moving seat 523, it will further push the moving seat 523 to move, thereby driving the corresponding first diverter member 4 or the second diverter member 5 to move. Figure 8The sliding cylinder 522 is exemplarily installed on the threaded rod 431 of the second driving member 52; it should be understood that, for the four threaded rods 431, one of the adjacent positions does not need to be installed with the bevel gear assembly 521 for transmission;

[0055] In addition, see Figure 7 , which represents the state that the first driving member 43 and the second driving member 52 drive the first diverter member 4 and the second diverter member 5 to move into or out of the gap 3 at the same time.

[0056] In one embodiment of the present invention, the first separator 42 and the second separator 51 are located at the gaps between the battery cells when they move out of the gap 3. The first separator 42 and the second separator 51 are both provided with avoidance grooves 8 for them to avoid each other when moving relative to each other.

[0057] In one embodiment of the present invention, a method for locating and detecting the thermal runaway position of a lithium battery is provided, which specifically comprises the following steps:

[0058] S101, moving the first flow dividing member 4 to form the first channels 41, detecting each first channel 41, and obtaining detection data corresponding to each first channel 41;

[0059] S102, moving the second flow dividing member 5 to form a second channel, detecting each second channel, and obtaining detection data corresponding to each second channel;

[0060] S103, locating the thermal runaway area;

[0061] It should be understood that when multiple thermal runaway locations occur, multiple locations can also be located;

[0062] It should be further explained that the setting of the detection device and the detection method in this solution can not only be directly applied to actual products, but can also be used for experiments and tests of battery packs.

[0063] The above only describes some exemplary embodiments of the present invention by way of illustration. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the present invention.

Claims

1. A lithium battery thermal runaway detection device, comprising a battery body and a housing, characterized in that: There is a gap for gas flow between the battery body and the shell, and a first diverter is arranged in the shell. The first diverter can move into or out of the gap, and when the first diverter moves into the gap, the gap is divided into a plurality of first channels in a first direction. At least one detection device is arranged on one side of the shell for detecting thermal runaway data of the gap or the first channel, and the first diverter is connected to a first driving mechanism for driving its movement.

2. A lithium battery thermal runaway detection device according to claim 1, characterized in that: A second flow divider is also arranged in the shell. The second flow divider can move into or out of the gap. When the second flow divider moves into the gap, it divides the gap into a plurality of second channels in the second direction.

3. A lithium battery thermal runaway detection device according to claim 1 or 2, characterized in that: The detection devices are respectively arranged on one side of each first channel and each second channel.

4. A lithium battery thermal runaway detection device according to claim 1 or 2, characterized in that: A detection device is respectively disposed on one side of the first channel and the second channel.

5. A lithium battery thermal runaway detection device according to claim 4, characterized in that: The detection device is connected with each first channel and / or each second channel in sequence through the alternating connecting device.

6. A lithium battery thermal runaway detection device according to claim 5, characterized in that: The alternating connection device includes a box body, a cavity for accommodating the detection device is opened in the box body, and a diversion channel connecting the cavity and each first channel respectively is opened in the box body, and a switch component for closing or opening the diversion channel is arranged in the box body.

7. A lithium battery thermal runaway detection device according to claim 6, characterized in that: The cavity is circular, and the outlet of the guide channel is located on the peripheral side of the cavity. The switching component includes an arc-shaped door plate, which abuts against the peripheral side of the cavity and can rotate around the axis of the cavity. When the arc-shaped door plate moves to the outlet position of the guide channel, the guide channel is closed. The arc-shaped door plate is connected to a rotating part for driving its rotation.

8. A lithium battery thermal runaway detection device according to claim 7, characterized in that: The rotating member includes a rotating ring located in the cavity and rotatably connected to the inner wall of the box body. A tooth portion is provided on the inner side of the rotating ring. The tooth portion is meshed with a first gear. The first gear is rotatably connected to the box body, and one side of the first gear is fixedly connected to one end of the output shaft of the motor.

9. A lithium battery thermal runaway detection device according to claim 2, characterized in that: The second flow dividing member is connected to a second driving mechanism for driving the movement of the second flow dividing member.

10. A method for detecting thermal runaway of a lithium battery, applicable to the device for detecting thermal runaway of a lithium battery as claimed in any one of claims 1 to 9, characterized in that: The specific steps include: S101, moving the first flow dividing member to form a first channel, detecting each first channel, and obtaining detection data corresponding to each first channel; S102, moving the second flow dividing member to form a second channel, detecting each second channel, and obtaining detection data corresponding to each second channel; S103. Locate the thermal runaway area.

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