Battery module and battery pack
By alternately aligning the battery cell sets in the battery module and clamping the insulation pads and buffer pads, the spatial deviation and thermal runaway caused by cell size tolerance and expansion are solved, and the safety and life of the battery module are improved.
Patent Information
- Application Number
- CN202421726204.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-19
- Publication Date
- 2025-05-30
- Estimated Expiration
- 2034-07-19
AI Technical Summary
During assembly and use, existing battery modules have deviations in space due to cell size tolerance and expansion, which affects safety and life, and also has the risk of thermal runaway.
A battery module is designed in which the battery cell rows are alternately arranged in a first direction, a first thermal insulation pad is clamped to prevent thermal runaway, and a buffer pad is clamped between each adjacent battery cell to absorb dimensional tolerances and expansion.
Effectively prevents the spread of heat out of control, absorbs the dimensional tolerance and expansion dimension of the battery cell in the first direction, and improves the safety and service life of the battery module.
Smart Images
Figure CN222927614U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, in particular to a battery module and a battery pack. Background Art
[0002] In the related art, multiple battery cells are arranged in a square matrix along two directions to form a battery module, and then the battery module is installed in a battery box to form a battery pack.
[0003] During actual assembly, due to the dimensional tolerance of the actual thickness dimension of the battery cells, after multiple battery cells form a battery module, there is a deviation between the actual size of the battery module and the designed size. Furthermore, there is a deviation between the actual occupied space of the battery module installed in the battery box and the designed occupied space. In addition, when the battery cells are charged and discharged, the battery cells will expand. The way that the battery cells are arranged in sequence in contact with each other easily squeezes the battery cells, thereby affecting the use safety and service life of the battery cells. How to offset the dimensional tolerance of the battery cells and the increased thickness caused by the expansion of the battery cells is an urgent problem to be solved by those skilled in the art.
[0004] On the other hand, the battery cells continuously charged and discharged in a high-temperature environment are at risk of thermal runaway. How to effectively prevent the spread of thermal runaway of the battery cells is also an urgent problem to be solved by those skilled in the art.
[0005] Therefore, it is urgent to propose a battery module and a battery pack to solve the above technical problems. Summary of the Utility Model
[0006] The first object of the utility model is to provide a battery module, the design of which can not only prevent the spread of thermal runaway but also absorb the dimensional tolerance and expansion size of the battery cells in the first direction.
[0007] To achieve this purpose, the utility model adopts the following technical solutions:
[0008] The battery module includes a battery cell row, the battery cell row includes multiple first battery cell groups and multiple second battery cell groups, the multiple first battery cell groups and the multiple second battery cell groups are alternately arranged along the first direction, a first heat insulation pad is clamped between each adjacent first battery cell group and second battery cell group, both the first battery cell group and the second battery cell group include at least two battery cells arranged along the first direction, and a buffer pad is clamped between each adjacent two battery cells in the first battery cell group and the second battery cell group.
[0009] Optionally, the compression rate of the first heat insulation pad is less than that of the buffer pad.
[0010] Optionally, the compression rate of the buffer pad is greater than or equal to 40%.
[0011] Optionally, the buffer pad is a flame retardant.
[0012] Optionally, the number of the first battery cell groups is three, each first battery cell group includes three battery cells, the number of the second battery cell groups is two, each second battery cell group includes two battery cells, and at both ends of the battery cell row in the first direction are the first battery cell groups.
[0013] Optionally, a hollowed-out portion is provided on the surface of the buffer pad.
[0014] Optionally, the distance between any two opposite inner walls of the hollowed-out portion is greater than the distance between any inner wall of the hollowed-out portion and the corresponding side wall of the buffer pad.
[0015] Optionally, the distance between any inner wall of the hollowed-out portion and the corresponding side wall of the buffer pad is 15 mm - 25 mm.
[0016] Optionally, the number of the battery cell rows is at least two, at least two battery cell rows are arranged in the second direction, and a second heat insulation pad is clamped between every two adjacent battery cell rows, and the second direction is perpendicular to the first direction.
[0017] The second object of the present utility model is to provide a battery pack, which has a good ability to resist the spread of thermal runaway and can also absorb the dimensional tolerance and expansion size of the battery cells in the first direction.
[0018] To achieve this object, the present utility model adopts the following technical solutions:
[0019] The battery pack includes a battery box and the above-mentioned battery module, and the battery module is arranged in the battery box.
[0020] The beneficial effects of the present utility model:
[0021] In the battery module provided by the present utility model, a plurality of first battery cell groups and a plurality of second battery cell groups are arranged alternately in the first direction, and both the first battery cell groups and the second battery cell groups include at least two battery cells arranged in the first direction. A first heat insulation pad is clamped between every two adjacent first battery cell groups and second battery cell groups, and in both the first battery cell groups and the second battery cell groups, a buffer pad is clamped between every two adjacent battery cells. When one or several battery cells undergo thermal runaway, the first heat insulation pad can block the spread of heat. When there is a dimensional tolerance of the battery cells in the first direction and when the battery cells expand, the buffer pad is compressed to absorb the dimensional tolerance of the battery cells and the expansion amount of the battery cells. It can be seen that the design of this battery module can not only block the spread of thermal runaway but also absorb the dimensional tolerance and expansion size of the battery cells in the first direction.
[0022] The battery pack provided by the present utility model adopts the above-mentioned battery module, has a good ability to resist the spread of thermal runaway, and can also absorb the dimensional tolerance and expansion size of the battery cells in the first direction. Description of the Drawings
[0023] Figure 1It is a schematic structural diagram of a battery cell row provided in the first embodiment of the present utility model;
[0024] Figure 2 It is a schematic structural diagram of a buffer pad provided in the first embodiment of the present utility model;
[0025] Figure 3 It is a schematic structural diagram of a first heat insulation pad provided in the first embodiment of the present utility model;
[0026] Figure 4 It is a schematic structural diagram of a battery module (without showing the buffer pad) provided in the first embodiment of the present utility model;
[0027] Figure 5 It is a schematic structural diagram of a battery module (without showing the buffer pad) provided in the comparative example;
[0028] Figure 6 It is a schematic structural diagram of a buffer pad provided in the second embodiment of the present utility model.
[0029] In the figure:
[0030] 100, battery cell row; 110, first battery cell group; 120, second battery cell group; 130, battery cell; 140, third battery cell group; 210, first heat insulation pad; 220, second heat insulation pad; 300, buffer pad; 310, hollow part; 400, heating film. Detailed implementation manners
[0031] The following further elaborates on the present utility model in conjunction with the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present utility model, rather than limiting the present utility model. Additionally, it should be noted that for the sake of description, only the parts related to the present utility model rather than all the structures are shown in the drawings.
[0032] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0033] In the present utility model, unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "beneath" and "underneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is lower than that of the second feature.
[0034] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "right", etc. are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.
[0035] Embodiment 1
[0036] This embodiment provides a battery module, and the design of this battery module can not only prevent the spread of thermal runaway but also absorb the dimensional tolerance and expansion dimension of the battery cells in the first direction.
[0037] Specifically, as Figure 1 shown, the battery module includes a battery cell row 100, and the battery cell row 100 includes a plurality of first battery cell groups 110 and a plurality of second battery cell groups 120. The plurality of first battery cell groups 110 and the plurality of second battery cell groups 120 are arranged alternately along the first direction ( Figure 1 the x direction in
[0038] Based on the above design, multiple first battery cell groups 110 and multiple second battery cell groups 120 are arranged alternately along the first direction. Both the first battery cell groups 110 and the second battery cell groups 120 include at least two battery cells 130 arranged along the first direction. A first heat insulation pad 210 is provided between every two adjacent first battery cell groups 110 and second battery cell groups 120. And between every two adjacent battery cells 130 in the first battery cell groups 110 and the second battery cell groups 120, a buffer pad 300 is provided. When one or several battery cells 130 experience thermal runaway, the first heat insulation pad 210 can block the spread of heat. When there are dimensional tolerances in the first direction of the battery cells 130 and when the battery cells 130 expand, the buffer pad 300 is compressed to absorb the dimensional tolerances of the battery cells 130 and the expansion amount of the battery cells 130. It can be seen that the design of this battery module can not only block the spread of thermal runaway but also absorb the dimensional tolerances and expansion dimensions of the battery cells 130 in the first direction.
[0039] Further, as Figure 1 shown, the number of the first battery cell groups 110 is three, and each first battery cell group 110 includes three battery cells 130. The number of the second battery cell groups 120 is two, and each second battery cell group 120 includes two battery cells 130. At both ends of the battery cell row 100 in the first direction are the first battery cell groups 110. That is to say, in this embodiment, the battery cell row 100 includes thirteen battery cells 130. Among the thirteen battery cells 130, every three battery cells 130 form a first battery cell group 110, and every two battery cells 130 form a second battery cell group 120. Thus, three first battery cell groups 110 and two second battery cell groups 120 are formed. The three first battery cell groups 110 and the two second battery cell groups 120 are alternately arranged in sequence along the first direction, and the two first battery cell groups 110 are respectively arranged at the head end and the tail end of the battery cell row 100. This structural design can maximize the ability of the battery cell row 100 to resist the spread of thermal runaway, thereby improving the safety of the battery module.
[0040] In other implementation schemes, the number of the first battery cell groups 110 can also be two, four, five, six, eight, etc., and the number of the second battery cell groups 120 can also be three, four, five, six, seven, etc. Moreover, the number of the first battery cell groups 110 and the second battery cell groups 120 can be the same or different.
[0041] In other implementation schemes, the number of the battery cells 130 in the first battery cell groups 110 can also be two, four, five, six, eight, etc., and the number of the battery cells 130 in the second battery cell groups 120 can also be three, four, five, six, seven, etc. And the number of the battery cells 130 in the first battery cell groups 110 and the number of the battery cells 130 in the second battery cell groups 120 can be the same or different.
[0042] Optionally, the compression ratio of the buffer pad 300 is greater than or equal to 40%. Exemplarily, the compression ratio of the buffer pad 300 can be 40%, 50%, or 60%, etc., so that the buffer pad 300 has sufficient ability to absorb the dimensional tolerance of the battery cell 130 and the expansion amount of the battery cell 130. In this embodiment, when the compression amount of the buffer pad 300 reaches the maximum, its thickness is 1 mm.
[0043] Optionally, the buffer pad 300 is a flame retardant component, so that while the buffer pad 300 can absorb the dimensional tolerance of the battery cell 130 and the expansion amount of the battery cell 130, it also has a certain flame retardant and heat insulation effect, which can further improve the ability of the battery module to resist the spread of thermal runaway.
[0044] Furthermore, the buffer pad 300 can be a high compression amount flame retardant silica gel or a flame retardant foam, etc.
[0045] Optionally, the compression ratio of the first heat insulation pad 210 is less than that of the buffer pad 300, so that the overall battery cell row 100 has a certain structural strength and can also avoid the problem that the excessive expansion of the battery cell 130 causes the deformation amount of the battery cell row 100 in the first direction to be too large.
[0046] Optionally, the first heat insulation pad 210 can be a silica gel pad made of a nano-micro pore heat insulation material or an aerogel.
[0047] Optionally, the two surfaces of the buffer pad 300 are respectively bonded to the two battery cells 130, so as to avoid the problem that the buffer pad 300 is displaced due to factors such as vibration.
[0048] Optionally, one surface of the first heat insulation pad 210 is bonded to the battery cell 130 in the corresponding first battery cell group 110, and the other surface of the first heat insulation pad 210 is bonded to the battery cell 130 in the corresponding second battery cell group 120, so as to avoid the problem that the first heat insulation pad 210 is displaced due to factors such as vibration.
[0049] In this embodiment, as Figure 2 shown, the buffer pad 300 is a complete sheet-like structure, so that the buffer pad 300 can fully absorb the dimensional tolerance of the battery cell 130 and the expansion amount of the battery cell 130. The distance between the two side walls of the buffer pad 300 and the two side walls of the battery cell 130 is a, and a is less than or equal to 5 mm. For example, a can be 5 mm, 4 mm, or 2 mm, etc. The distance between the bottom of the buffer pad 300 and the bottom of the battery cell 130 is b, and b is less than or equal to 5 mm. For example, b can be 5 mm, 4 mm, or 2 mm, etc. The distance between the top of the buffer pad 300 and the top of the battery cell 130 is c, and c is less than or equal to 15 mm. For example, c can be 15 mm, 10 mm, or 8 mm, etc., so that the buffer pad 300 is approximately located at the center position of the battery cell 130 and can also avoid the welding area between the top of the battery cell 130 and other components.
[0050] In this embodiment, as Figure 3 shown, the first heat insulation pad 210 is a complete sheet structure to improve the ability of the first heat insulation pad 210 to prevent the spread of thermal runaway. The distance between the two side walls of the first heat insulation pad 210 and the two side walls of the battery cell 130 is d, and d is less than or equal to 4 mm. For example, d can be 4 mm, 3 mm, or 2 mm, etc. The distance between the bottom of the first heat insulation pad 210 and the bottom of the battery cell 130 is e, and e is less than or equal to 5 mm. For example, e can be 5 mm, 4 mm, or 2 mm, etc. The distance between the top of the first heat insulation pad 210 and the top of the battery cell 130 is f, and f is less than or equal to 15 mm. For example, f can be 15 mm, 10 mm, or 8 mm, etc. This makes the first heat insulation pad 210 roughly located at the center of the battery cell 130 and can also avoid the welding area between the top of the battery cell 130 and other components.
[0051] Optionally, as Figure 4 shown, the number of the battery cell rows 100 is at least two, and at least two battery cell rows 100 are arranged along the second direction ( Figure 4 the y direction in
[0052] ). The second direction is in the same plane as the first direction and perpendicular to each other. A second heat insulation pad 220 is provided between every two adjacent battery cell rows 100 to further improve the ability of the battery module to resist the spread of thermal runaway. Optionally, the number of the battery cell rows 100 can be two, three, four, or five, etc., depending on the actual application.
[0053] The following takes several groups of specific test data as examples to illustrate the ability of the battery module provided in this embodiment to resist the spread of thermal runaway:
[0053] The first example
[0054] The first example adopts the battery module structure provided in this embodiment. For easy understanding, the battery cells 130 in the battery module are numbered here, specifically as Figure 4 shown. The first heat insulation pad 210 in the first example is a silica gel pad made of nano-porous heat insulation material.
[0055] Test conditions: A heating film 400 is provided on each side of the 20# battery cell 130, and it is heated at a temperature rise rate of 4.5 °C / min until the battery cell 130 triggers thermal runaway; it is left standing and observed for at least 24 h until the temperature of all battery cells 130 drops to a safe temperature. If there is a fire or explosion, the test is stopped in advance. The determination criterion for thermal runaway: There is an obvious change in the temperature rise slope.
[0056] Test results: Thermal runaway occurred in cell 130 of No. 19, cell 130 of No. 20, and cell 130 of No. 21. The maximum thermal insulation temperature difference between cell 130 of No. 18 and cell 130 of No. 19 was 319 °C, and the maximum thermal insulation temperature difference between cell 130 of No. 21 and cell 130 of No. 22 was 196 °C.
[0057] The second example
[0058] The second example adopts the battery module structure as Figure 5 shown, that is, the cell row 100 includes three first cell groups 110 and one third cell group 140. The first cell group 110 includes three cells 130 arranged in sequence along the first direction ( Figure 5 the x-direction in Figure 5 ), and the third cell group 140 includes three cells 130 arranged in sequence along the first direction. In the first direction, the three first cell groups 110 are arranged in sequence, and the third cell group 140 is located behind the last first cell group 110. Four cell rows 100 are arranged in sequence along the second direction ( Figure 5 the y-direction in
[0059] ), and a second thermal insulation pad 220 is interposed between every two cell rows 100. For ease of understanding, the cells 130 in the battery module are numbered here, specifically as
[0060] shown. The first thermal insulation pad 210 in the second example is a silica gel pad made of nano-porous thermal insulation material.
[0061] The third example
[0062] The third example adopts the battery module structure provided in this embodiment. For ease of understanding, the cells 130 in the battery module are numbered here, specifically as Figure 4 shown. The first thermal insulation pad 210 in the third example is a silica gel pad made of aerogel.
[0063] Test conditions: A heating film 400 is respectively arranged on the left and right sides of the 20# battery cell 130 and heated at a temperature rise rate of 4.5 °C / min until the thermal runaway of the battery cell 130 is triggered; observe statically for at least 24 h until the temperatures of all battery cells 130 drop to a safe temperature, and stop the test in advance if there is fire or explosion. Judgment criterion for thermal runaway: There is an obvious change in the temperature rise slope.
[0064] Test results: The 19# battery cell 130, 20# battery cell 130, and 21# battery cell 130 experienced thermal runaway. The maximum thermal insulation temperature difference between the 18# battery cell 130 and the 19# battery cell 130 was 195 °C, and the maximum thermal insulation temperature difference between the 21# battery cell 130 and the 22# battery cell 130 was 199 °C.
[0065] The fourth example
[0066] The fourth example adopts the battery module structure as Figure 5 shown. For ease of understanding, each battery cell 130 in the battery module is numbered here, specifically as Figure 5 shown. The first thermal insulation pad 210 in the fourth example is a silica gel pad made of aerogel.
[0067] Test conditions: A heating film 400 is respectively arranged on the left and right sides of the 20# battery cell 130 and heated at a temperature rise rate of 4.5 °C / min until the thermal runaway of the battery cell 130 is triggered; observe statically for at least 24 h until the temperatures of all battery cells 130 drop to a safe temperature, and stop the test in advance if there is fire or explosion. Judgment criterion for thermal runaway: There is an obvious change in the temperature rise slope.
[0068] Test results: The 19# battery cell 130, 20# battery cell 130, 21# battery cell 130, 22# battery cell 130, and 23# battery cell 130 experienced thermal runaway. The maximum thermal insulation temperature difference between the 17# battery cell 130 and the 18# battery cell 130 was 20 °C. From the above data, it can be found that the battery module provided in this embodiment has better thermal runaway propagation resistance ability, which can provide a strong guarantee for the use safety of the battery pack.
[0069] This embodiment also provides a battery pack, which has better thermal runaway propagation resistance ability and can also absorb the dimensional tolerance and expansion size of the battery cell 130 in the first direction.
[0070] Specifically, the battery pack includes a battery box and the above-mentioned battery module, and the battery module is arranged in the battery box. The battery pack adopts the above-mentioned battery module, has better thermal runaway propagation resistance ability, and can also absorb the dimensional tolerance and expansion size of the battery cell 130 in the first direction.
[0071] Example two
[0072] This embodiment provides a battery module, which is different from the battery module provided in Embodiment 1 in that:
[0073] As Figure 6 shown, a hollowed-out portion 310 is provided on the surface of the buffer pad 300, reserving a certain space for the expansion of the battery cell 130, reducing the probability that the buffer pad 300 has been compressed to the minimum but the battery cell 130 still needs to continue expanding, and providing a strong guarantee for extending the service life of the battery cell 130 and improving the use safety of the battery module.
[0074] Furthermore, the distance between any two opposite inner walls of the hollowed-out portion 310 is greater than the distance between any inner wall of the hollowed-out portion 310 and the corresponding side wall of the buffer pad 300, so as to expand the area of the hollowed-out portion 310 as much as possible and reserve sufficient expansion space for the battery cell 130.
[0075] Optionally, the distance between any inner wall of the hollowed-out portion 310 and the corresponding side wall of the buffer pad 300 is 15 mm - 25 mm. In this embodiment, both the buffer pad 300 and the hollowed-out portion 310 are square, and each side wall of the buffer pad 300 is parallel to the inner wall of the corresponding hollowed-out portion 310. The distance between each side wall of the buffer pad 300 and the inner wall of the corresponding hollowed-out portion 310 is 15 mm - 25 mm. Exemplarily, this distance can be 15 mm, 20 mm or 25 mm, etc. If this distance is less than 15 mm, the reliability of the adhesion between the buffer pad 300 and the battery cell 130 will be reduced. If this distance is greater than 25 mm, the reserved expansion space for the battery cell 130 will be reduced. To reduce the production difficulty, in actual production, a dimensional tolerance of ±0.5 mm is allowed for the above distance.
[0076] The remaining structures of the battery module provided in this embodiment are the same as those in Embodiment 1 and will not be described in detail.
[0077] Obviously, the above embodiments of the present invention are only examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.
Claims
1. A battery module, characterized in that: The invention comprises a battery cell row (100), wherein the battery cell row (100) comprises a plurality of first battery cell groups (110) and a plurality of second battery cell groups (120), wherein the plurality of first battery cell groups (110) and the plurality of second battery cell groups (120) are alternately arranged along a first direction, and a first thermal insulation pad (210) is sandwiched between each adjacent first battery cell group (110) and second battery cell group (120), and the first battery cell group (110) and the second battery cell group (120) each comprise at least two battery cells (130) arranged along the first direction, and a buffer pad (300) is sandwiched between each adjacent two battery cells (130) in the first battery cell group (110) and the second battery cell group (120).
2. The battery module according to claim 1, characterized in that: The compression rate of the first thermal insulation pad (210) is lower than the compression rate of the buffer pad (300).
3. The battery module according to claim 1, characterized in that: The compression rate of the buffer pad (300) is greater than or equal to 40%.
4. The battery module according to claim 1, characterized in that: The buffer pad (300) is a flame retardant component.
5. The battery module according to claim 1, characterized in that: The number of the first battery cell groups (110) is three, and the first battery cell group (110) includes three battery cells (130); the number of the second battery cell groups (120) is two, and the second battery cell group (120) includes two battery cells (130); and in the first direction, both ends of the battery cell row (100) are the first battery cell groups (110).
6. The battery module according to any one of claims 1 to 5, characterized in that: A hollow portion (310) is provided on the surface of the buffer pad (300).
7. The battery module according to claim 6, characterized in that: The distance between any two opposite inner walls of the hollow portion (310) is greater than the distance between any inner wall of the hollow portion (310) and the corresponding side wall of the buffer pad (300).
8. The battery module according to claim 6, characterized in that: The distance between any inner wall of the hollow portion (310) and the corresponding side wall of the buffer pad (300) is 15 mm to 25 mm.
9. The battery module according to any one of claims 1 to 5, characterized in that: The number of the battery cell rows (100) is at least two, at least two of the battery cell rows (100) are arranged along a second direction, a second thermal insulation pad (220) is sandwiched between each two adjacent battery cell rows (100), and the second direction is perpendicular to the first direction.
10. A battery pack, characterized in that: It comprises a battery box and the battery module according to any one of claims 1 to 9, wherein the battery module is arranged in the battery box.
Citation Information
Cited By
Battery device, energy storage device, energy storage system and charging network
WO2026113404A1